1
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Romo BA, Karakyriakou B, Cressey L, Brauer BL, Yang H, Warren A, Johnson AL, Kettenbach AN, Miller TW. TRIM33 Is a Co-Regulator of Estrogen Receptor Alpha. Cancers (Basel) 2024; 16:845. [PMID: 38473207 PMCID: PMC10930732 DOI: 10.3390/cancers16050845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 02/15/2024] [Accepted: 02/17/2024] [Indexed: 03/14/2024] Open
Abstract
Estrogen receptor alpha (ER)-positive breast cancer is responsible for over 60% of breast cancer cases in the U.S. Among patients diagnosed with early-stage ER+ disease, 1/3 will experience recurrence despite treatment with adjuvant endocrine therapy. ER is a nuclear hormone receptor responsible for estrogen-driven tumor growth. ER transcriptional activity is modulated by interactions with coregulators. Dysregulation of the levels of these coregulators is involved in the development of endocrine resistance. To identify ER interactors that modulate transcriptional activity in breast cancer, we utilized biotin ligase proximity profiling of ER interactomes. Mass spectrometry analysis revealed tripartite motif containing 33 (TRIM33) as an estrogen-dependent interactor of ER. shRNA knockdown showed that TRIM33 promoted ER transcriptional activity and estrogen-induced cell growth. Despite its known role as an E3 ubiquitin ligase, TRIM33 increased the stability of endogenous ER in breast cancer cells. TRIM33 offers a novel target for inhibiting estrogen-induced cancer cell growth, particularly in cases of endocrine resistance driven by ER (ESR1) gene amplification or overexpression.
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Affiliation(s)
- Bianca A. Romo
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Barbara Karakyriakou
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Lauren Cressey
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Brooke L. Brauer
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Huijuan Yang
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Alexa Warren
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Anneka L. Johnson
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
| | - Todd W. Miller
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03755, USA
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Pathology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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2
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Stanford SM, Nguyen TP, Chang J, Zhao Z, Hackman GL, Santelli E, Sanders CM, Katiki M, Dondossola E, Brauer BL, Diaz MA, Zhan Y, Ramsey SH, Watson PA, Sankaran B, Paindelli C, Parietti V, Mikos AG, Lodi A, Bagrodia A, Elliott A, McKay RR, Murali R, Tiziani S, Kettenbach AN, Bottini N. Targeting prostate tumor low-molecular weight tyrosine phosphatase for oxidation-sensitizing therapy. Sci Adv 2024; 10:eadg7887. [PMID: 38295166 PMCID: PMC10830117 DOI: 10.1126/sciadv.adg7887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 12/29/2023] [Indexed: 02/02/2024]
Abstract
Protein tyrosine phosphatases (PTPs) play major roles in cancer and are emerging as therapeutic targets. Recent reports suggest low-molecular weight PTP (LMPTP)-encoded by the ACP1 gene-is overexpressed in prostate tumors. We found ACP1 up-regulated in human prostate tumors and ACP1 expression inversely correlated with overall survival. Using CRISPR-Cas9-generated LMPTP knockout C4-2B and MyC-CaP cells, we identified LMPTP as a critical promoter of prostate cancer (PCa) growth and bone metastasis. Through metabolomics, we found that LMPTP promotes PCa cell glutathione synthesis by dephosphorylating glutathione synthetase on inhibitory Tyr270. PCa cells lacking LMPTP showed reduced glutathione, enhanced activation of eukaryotic initiation factor 2-mediated stress response, and enhanced reactive oxygen species after exposure to taxane drugs. LMPTP inhibition slowed primary and bone metastatic prostate tumor growth in mice. These findings reveal a role for LMPTP as a critical promoter of PCa growth and metastasis and validate LMPTP inhibition as a therapeutic strategy for treating PCa through sensitization to oxidative stress.
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Affiliation(s)
| | - Tiffany P. Nguyen
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Joseph Chang
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Zixuan Zhao
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - G. Lavender Hackman
- Department of Nutritional Sciences, College of Natural Sciences and Department of Pediatrics, Dell Medical School, The University of Texas at Austin, Austin, TX, USA
| | - Eugenio Santelli
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
- Kao Autoimmunity Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Colton M. Sanders
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | | | - Eleonora Dondossola
- Department of Genitourinary Medical Oncology and David H. Koch Center for Applied Research of Genitourinary Cancers, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Brooke L. Brauer
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Michael A. Diaz
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Yuan Zhan
- Department of Pediatrics and Department of Oncology, Dell Medical School, Livestrong Cancer Institutes, College of Natural Sciences, The University of Texas at Austin, Austin, TX USA
| | - Sterling H. Ramsey
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Philip A. Watson
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Banumathi Sankaran
- Department of Molecular Biophysics and Integrated Bioimaging, Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Claudia Paindelli
- Department of Genitourinary Medical Oncology and David H. Koch Center for Applied Research of Genitourinary Cancers, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Vanessa Parietti
- Department of Genitourinary Medical Oncology and David H. Koch Center for Applied Research of Genitourinary Cancers, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Alessia Lodi
- Department of Nutritional Sciences, College of Natural Sciences and Department of Pediatrics, Dell Medical School, The University of Texas at Austin, Austin, TX, USA
| | - Aditya Bagrodia
- Department of Urology, University of California, San Diego, La Jolla, CA, USA
| | - Andrew Elliott
- Department of Clinical and Translational Research, Caris Life Sciences, Phoenix, AZ, USA
| | - Rana R. McKay
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Ramachandran Murali
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Stefano Tiziani
- Department of Nutritional Sciences, College of Natural Sciences and Department of Pediatrics, Dell Medical School, The University of Texas at Austin, Austin, TX, USA
- Department of Pediatrics and Department of Oncology, Dell Medical School, Livestrong Cancer Institutes, College of Natural Sciences, The University of Texas at Austin, Austin, TX USA
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Nunzio Bottini
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
- Kao Autoimmunity Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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3
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Hein JB, Nguyen HT, Garvanska DH, Nasa I, Kruse T, Feng Y, Lopez Mendez B, Davey N, Kettenbach AN, Fordyce PM, Nilsson J. Phosphatase specificity principles uncovered by MRBLE:Dephos and global substrate identification. Mol Syst Biol 2023; 19:e11782. [PMID: 37916966 PMCID: PMC10698503 DOI: 10.15252/msb.202311782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 10/14/2023] [Accepted: 10/16/2023] [Indexed: 11/03/2023] Open
Abstract
Phosphoprotein phosphatases (PPPs) regulate major signaling pathways, but the determinants of phosphatase specificity are poorly understood. This is because methods to investigate this at scale are lacking. Here, we develop a novel in vitro assay, MRBLE:Dephos, that allows multiplexing of dephosphorylation reactions to determine phosphatase preferences. Using MRBLE:Dephos, we establish amino acid preferences of the residues surrounding the dephosphorylation site for PP1 and PP2A-B55, which reveals common and unique preferences. To compare the MRBLE:Dephos results to cellular substrates, we focused on mitotic exit that requires extensive dephosphorylation by PP1 and PP2A-B55. We use specific inhibition of PP1 and PP2A-B55 in mitotic exit lysates coupled with phosphoproteomics to identify more than 2,000 regulated sites. Importantly, the sites dephosphorylated during mitotic exit reveal key signatures that are consistent with MRBLE:Dephos. Furthermore, integration of our phosphoproteomic data with mitotic interactomes of PP1 and PP2A-B55 provides insight into how binding of phosphatases to substrates shapes dephosphorylation. Collectively, we develop novel approaches to investigate protein phosphatases that provide insight into mitotic exit regulation.
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Affiliation(s)
- Jamin B Hein
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Department of BioengineeringStanford UniversityStanfordCAUSA
| | - Hieu T Nguyen
- Biochemistry and Cell BiologyGeisel School of Medicine at Dartmouth CollegeHanoverNHUSA
| | - Dimitriya H Garvanska
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Isha Nasa
- Department of BioengineeringStanford UniversityStanfordCAUSA
| | - Thomas Kruse
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Yinnian Feng
- Department of GeneticsStanford UniversityStanfordCAUSA
| | - Blanca Lopez Mendez
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Norman Davey
- Division of Cancer BiologyThe Institute of Cancer ResearchLondonUK
| | - Arminja N Kettenbach
- Biochemistry and Cell BiologyGeisel School of Medicine at Dartmouth CollegeHanoverNHUSA
| | - Polly M Fordyce
- Department of BioengineeringStanford UniversityStanfordCAUSA
- Department of GeneticsStanford UniversityStanfordCAUSA
- Sarafan ChEM‐HStanford UniversityStanfordCAUSA
- Chan Zuckerberg BiohubSan FranciscoCAUSA
| | - Jakob Nilsson
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
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4
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Malik HS, Magnotti F, Loeven NA, Delgado JM, Kettenbach AN, Henry T, Bliska JB. Phosphoprotein phosphatase activity positively regulates oligomeric pyrin to trigger inflammasome assembly in phagocytes. mBio 2023; 14:e0206623. [PMID: 37787552 PMCID: PMC10653879 DOI: 10.1128/mbio.02066-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 08/14/2023] [Indexed: 10/04/2023] Open
Abstract
IMPORTANCE Pyrin, a unique cytosolic receptor, initiates inflammatory responses against RhoA-inactivating bacterial toxins and effectors like Yersinia's YopE and YopT. Understanding pyrin regulation is crucial due to its association with dysregulated inflammatory responses, including Familial Mediterranean Fever (FMF), linked to pyrin gene mutations. FMF mutations historically acted as a defense mechanism against plague. Negative regulation of pyrin through PKN phosphorylation is well established, with Yersinia using the YopM effector to promote pyrin phosphorylation and counteract its activity. This study highlights the importance of phosphoprotein phosphatase activity in positively regulating pyrin inflammasome assembly in phagocytic cells of humans and mice. Oligomeric murine pyrin has S205 phosphorylated before inflammasome assembly, and this study implicates the dephosphorylation of murine pyrin S205 by two catalytic subunits of PP2A in macrophages. These findings offer insights for investigating the regulation of oligomeric pyrin and the balance of kinase and phosphatase activity in pyrin-associated infectious and autoinflammatory diseases.
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Affiliation(s)
- Haleema S. Malik
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Flora Magnotti
- CIRI, Centre International de Recherche en Infectiologie, Inserm U111, Université Claude Bernard Lyon, CNRS, UMR5308, ENS de Lyon, Univ Lyon, Lyon, France
| | - Nicole A. Loeven
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jose M. Delgado
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
- Dartmouth Cancer Center, Lebanon, New Hampshire, USA
| | - Thomas Henry
- CIRI, Centre International de Recherche en Infectiologie, Inserm U111, Université Claude Bernard Lyon, CNRS, UMR5308, ENS de Lyon, Univ Lyon, Lyon, France
| | - James B. Bliska
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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5
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Smolen KA, Papke CM, Swingle MR, Musiyenko A, Li C, Salter EA, Camp AD, Honkanen RE, Kettenbach AN. Quantitative proteomics and phosphoproteomics of PP2A-PPP2R5D variants reveal deregulation of RPS6 phosphorylation via converging signaling cascades. J Biol Chem 2023; 299:105154. [PMID: 37572851 PMCID: PMC10485637 DOI: 10.1016/j.jbc.2023.105154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 07/28/2023] [Accepted: 07/29/2023] [Indexed: 08/14/2023] Open
Abstract
Genetic germline variants of PPP2R5D (encoding: phosphoprotein phosphatase 2 regulatory protein 5D) result in PPP2R5D-related disorder (Jordan's Syndrome), which is characterized by intellectual disability, hypotonia, seizures, macrocephaly, autism spectrum disorder, and delayed motor skill development. The disorder originates from de novo single nucleotide mutations, generating missense variants that act in a dominant manner. Pathogenic mutations altering 13 different amino acids have been identified, with the E198K variant accounting for ∼40% of reported cases. However, the generation of a heterozygous E198K variant cell line to study the molecular effects of the pathogenic mutation has been challenging. Here, we use CRISPR-PRIME genomic editing to introduce a transition (c.592G>A) in a single PPP2R5D allele in HEK293 cells, generating E198K-heterozygous lines to complement existing E420K variant lines. We generate global protein and phosphorylation profiles of WT, E198K, and E420K cell lines and find unique and shared changes between variants and WT cells in kinase- and phosphatase-controlled signaling cascades. We observed ribosomal protein S6 (RPS6) hyperphosphorylation as a shared signaling alteration, indicative of increased ribosomal protein S6-kinase activity. Treatment with rapamycin or an RPS6-kinase inhibitor (LY2584702) suppressed RPS6 phosphorylation in both, suggesting upstream activation of mTORC1/p70S6K. Intriguingly, our data suggests ERK-dependent activation of mTORC1 in both E198K and E420K variant cells, with additional AKT-mediated mTORC1 activation in the E420K variant. Thus, although upstream activation of mTORC1 differs between PPP2R5D-related disorder genotypes, inhibition of mTORC1 or RPS6 kinases warrants further investigation as potential therapeutic strategies for patients.
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Affiliation(s)
- Kali A Smolen
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Cinta M Papke
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Mark R Swingle
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Alla Musiyenko
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Chenchen Li
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - E Alan Salter
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Ashley D Camp
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Richard E Honkanen
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA.
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA.
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6
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Mariano NC, Rusin SF, Nasa I, Kettenbach AN. Inducible Protein Degradation as a Strategy to Identify Phosphoprotein Phosphatase 6 Substrates in RAS-Mutant Colorectal Cancer Cells. Mol Cell Proteomics 2023; 22:100614. [PMID: 37392812 PMCID: PMC10400926 DOI: 10.1016/j.mcpro.2023.100614] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 06/13/2023] [Accepted: 06/28/2023] [Indexed: 07/03/2023] Open
Abstract
Protein phosphorylation is an essential regulatory mechanism that controls most cellular processes, including cell cycle progression, cell division, and response to extracellular stimuli, among many others, and is deregulated in many diseases. Protein phosphorylation is coordinated by the opposing activities of protein kinases and protein phosphatases. In eukaryotic cells, most serine/threonine phosphorylation sites are dephosphorylated by members of the Phosphoprotein Phosphatase (PPP) family. However, we only know for a few phosphorylation sites which specific PPP dephosphorylates them. Although natural compounds such as calyculin A and okadaic acid inhibit PPPs at low nanomolar concentrations, no selective chemical PPP inhibitors exist. Here, we demonstrate the utility of endogenous tagging of genomic loci with an auxin-inducible degron (AID) as a strategy to investigate specific PPP signaling. Using Protein Phosphatase 6 (PP6) as an example, we demonstrate how rapidly inducible protein degradation can be employed to identify dephosphorylation sites and elucidate PP6 biology. Using genome editing, we introduce AID-tags into each allele of the PP6 catalytic subunit (PP6c) in DLD-1 cells expressing the auxin receptor Tir1. Upon rapid auxin-induced degradation of PP6c, we perform quantitative mass spectrometry-based proteomics and phosphoproteomics to identify PP6 substrates in mitosis. PP6 is an essential enzyme with conserved roles in mitosis and growth signaling. Consistently, we identify candidate PP6c-dependent dephosphorylation sites on proteins implicated in coordinating the mitotic cell cycle, cytoskeleton, gene expression, and mitogen-activated protein kinase (MAPK) and Hippo signaling. Finally, we demonstrate that PP6c opposes the activation of large tumor suppressor 1 (LATS1) by dephosphorylating Threonine 35 (T35) on Mps One Binder (MOB1), thereby blocking the interaction of MOB1 and LATS1. Our analyses highlight the utility of combining genome engineering, inducible degradation, and multiplexed phosphoproteomics to investigate signaling by individual PPPs on a global level, which is currently limited by the lack of tools for specific interrogation.
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Affiliation(s)
- Natasha C Mariano
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Scott F Rusin
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA.
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7
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Nguyen H, Kettenbach AN. Substrate and phosphorylation site selection by phosphoprotein phosphatases. Trends Biochem Sci 2023; 48:713-725. [PMID: 37173206 PMCID: PMC10523993 DOI: 10.1016/j.tibs.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 05/15/2023]
Abstract
Dynamic protein phosphorylation and dephosphorylation are essential regulatory mechanisms that ensure proper cellular signaling and biological functions. Deregulation of either reaction has been implicated in several human diseases. Here, we focus on the mechanisms that govern the specificity of the dephosphorylation reaction. Most cellular serine/threonine dephosphorylation is catalyzed by 13 highly conserved phosphoprotein phosphatase (PPP) catalytic subunits, which form hundreds of holoenzymes by binding to regulatory and scaffolding subunits. PPP holoenzymes recognize phosphorylation site consensus motifs and interact with short linear motifs (SLiMs) or structural elements distal to the phosphorylation site. We review recent advances in understanding the mechanisms of PPP site-specific dephosphorylation preference and substrate recruitment and highlight examples of their interplay in the regulation of cell division.
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Affiliation(s)
- Hieu Nguyen
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH 03755, USA
| | - Arminja N Kettenbach
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH 03755, USA; Dartmouth Cancer Center, Lebanon, NH 03756, USA.
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8
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Wiredu K, O’Connor S, Naseem H, Brauer BL, Kettenbach AN, Frost HR, Shaefi S, Gerber SA. Intraoperative plasma proteomic changes in cardiac surgery: In search of biomarkers of post-operative delirium. Proteomics Clin Appl 2023; 17:e2200066. [PMID: 36567636 PMCID: PMC10290728 DOI: 10.1002/prca.202200066] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 12/02/2022] [Accepted: 12/21/2022] [Indexed: 12/27/2022]
Abstract
PURPOSE Delirium presents a significant healthcare burden. It complicates post-operative care in up to 50% of cardiac surgical patients with worse outcomes, longer hospital stays and higher cost of care. Moreover, the nature of delirium following cardiac surgery with cardiopulmonary bypass (CPB) remains unclear, the underlying pathobiology is poorly understood, status quo diagnostic methods are subjective, and diagnostic biomarkers are currently lacking. OBJECTIVE To identify diagnostic biomarkers of delirium and for insights into possible neuronal pathomechanisms. EXPERIMENTAL DESIGN Comparative proteomic analyses were performed on plasma samples from a nested matched cohort of patients who underwent cardiac surgery. Validation by targeted proteomics was performed in an independent set of samples. Biomarkers were assessed for biological functions and diagnostic accuracy. RESULTS Forty-seven percent of subjects demonstrated delirium. Of 3803 proteins identified from patient samples by multiplexed quantitative proteomics, 16 were identified as signatures of exposure to CPB, and 11 biomarkers distinguished delirium cases from non-cases (AuROC = 93%). Notable among these biomarkers are C-reactive protein, serum amyloid A-1 and cathepsin-B. CONCLUSIONS AND CLINICAL RELEVANCE The interplay of systemic and central inflammatory markers sheds new light on delirium pathogenesis. This work suggests that accurate identification of cases may be achievable using panels of biomarkers.
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Affiliation(s)
- Kwame Wiredu
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH
- Department of Anesthesia, Critical Care and Pain Medicine, Mass General Hospital, Boston MA
- Department of Anaesthesia, Harvard Medical School, Boston MA
| | - Sean O’Connor
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Boston MA
| | - Heba Naseem
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Boston MA
| | - Brooke L. Brauer
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH
- Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Hildreth R. Frost
- Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
- Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Shahzad Shaefi
- Department of Anaesthesia, Harvard Medical School, Boston MA
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Boston MA
| | - Scott A. Gerber
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH
- Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
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9
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Wang B, Zhou X, Kettenbach AN, Mitchell HD, Markillie LM, Loros JJ, Dunlap JC. A crucial role for dynamic expression of components encoding the negative arm of the circadian clock. Nat Commun 2023; 14:3371. [PMID: 37291101 PMCID: PMC10250352 DOI: 10.1038/s41467-023-38817-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 05/17/2023] [Indexed: 06/10/2023] Open
Abstract
In the Neurospora circadian system, the White Collar Complex (WCC) drives expression of the principal circadian negative arm component frequency (frq). FRQ interacts with FRH (FRQ-interacting RNA helicase) and CKI, forming a stable complex that represses its own expression by inhibiting WCC. In this study, a genetic screen identified a gene, designated as brd-8, that encodes a conserved auxiliary subunit of the NuA4 histone acetylation complex. Loss of brd-8 reduces H4 acetylation and RNA polymerase (Pol) II occupancy at frq and other known circadian genes, and leads to a long circadian period, delayed phase, and defective overt circadian output at some temperatures. In addition to strongly associating with the NuA4 histone acetyltransferase complex, BRD-8 is also found complexed with the transcription elongation regulator BYE-1. Expression of brd-8, bye-1, histone h2a.z, and several NuA4 subunits is controlled by the circadian clock, indicating that the molecular clock both regulates the basic chromatin status and is regulated by changes in chromatin. Taken together, our data identify auxiliary elements of the fungal NuA4 complex having homology to mammalian components, which along with conventional NuA4 subunits, are required for timely and dynamic frq expression and thereby a normal and persistent circadian rhythm.
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Affiliation(s)
- Bin Wang
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA.
| | - Xiaoying Zhou
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA
| | - Hugh D Mitchell
- Biological Sciences Divisions, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Lye Meng Markillie
- Biological Sciences Divisions, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Jennifer J Loros
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA
| | - Jay C Dunlap
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA.
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10
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Wang B, Zhou X, Kettenbach AN, Mitchell HD, Markillie LM, Loros JJ, Dunlap JC. A crucial role for dynamic expression of components encoding the negative arm of the circadian clock. bioRxiv 2023:2023.04.24.538162. [PMID: 37162945 PMCID: PMC10168201 DOI: 10.1101/2023.04.24.538162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
In the Neurospora circadian system, the White Collar Complex (WCC) drives expression of the principal circadian negative arm component frequency ( frq ). FRQ interacts with FRH (FRQ-interacting helicase) and CK-1 forming a stable complex that represses its own expression by inhibiting WCC. In this study, a genetic screen identified a gene, designated as brd-8 , that encodes a conserved auxiliary subunit of the NuA4 histone acetylation complex. Loss of brd-8 reduces H4 acetylation and RNA polymerase (Pol) II occupancy at frq and other known circadian genes, and leads to a long circadian period, delayed phase, and defective overt circadian output at some temperatures. In addition to strongly associating with the NuA4 histone acetyltransferase complex, BRD-8 is also found complexed with the transcription elongation regulator BYE-1. Expression of brd-8, bye-1, histone hH2Az , and several NuA4 subunits is controlled by the circadian clock, indicating that the molecular clock both regulates the basic chromatin status and is regulated by changes in chromatin. Taken together, our data identify new auxiliary elements of the fungal NuA4 complex having homology to mammalian components, which along with conventional NuA4 subunits, are required for timely and dynamic frq expression and thereby a normal and persistent circadian rhythm.
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11
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Mariano NC, Rusin SF, Nasa I, Kettenbach AN. Inducible protein degradation as a strategy to identify Phosphoprotein Phosphatase 6 substrates in RAS-mutant colorectal cancer cells. bioRxiv 2023:2023.03.25.534211. [PMID: 36993243 PMCID: PMC10055397 DOI: 10.1101/2023.03.25.534211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Protein phosphorylation is an essential regulatory mechanism that controls most cellular processes, including cell cycle progression, cell division, and response to extracellular stimuli, among many others, and is deregulated in many diseases. Protein phosphorylation is coordinated by the opposing activities of protein kinases and protein phosphatases. In eukaryotic cells, most serine/threonine phosphorylation sites are dephosphorylated by members of the Phosphoprotein Phosphatase (PPP) family. However, we only know for a few phosphorylation sites which specific PPP dephosphorylates them. Although natural compounds such as calyculin A and okadaic acid inhibit PPPs at low nanomolar concentrations, no selective chemical PPP inhibitors exist. Here, we demonstrate the utility of endogenous tagging of genomic loci with an auxin-inducible degron (AID) as a strategy to investigate specific PPP signaling. Using Protein Phosphatase 6 (PP6) as an example, we demonstrate how rapidly inducible protein degradation can be employed to identify dephosphorylation SITES and elucidate PP6 biology. Using genome editing, we introduce AID-tags into each allele of the PP6 catalytic subunit (PP6c) in DLD-1 cells expressing the auxin receptor Tir1. Upon rapid auxin-induced degradation of PP6c, we perform quantitative mass spectrometry-based proteomics and phosphoproteomics to identify PP6 substrates in mitosis. PP6 is an essential enzyme with conserved roles in mitosis and growth signaling. Consistently, we identify candidate PP6c-dependent phosphorylation sites on proteins implicated in coordinating the mitotic cell cycle, cytoskeleton, gene expression, and mitogen-activated protein kinase (MAPK) and Hippo signaling. Finally, we demonstrate that PP6c opposes the activation of large tumor suppressor 1 (LATS1) by dephosphorylating Threonine 35 (T35) on Mps One Binder (MOB1), thereby blocking the interaction of MOB1 and LATS1. Our analyses highlight the utility of combining genome engineering, inducible degradation, and multiplexed phosphoproteomics to investigate signaling by individual PPPs on a global level, which is currently limited by the lack of tools for specific interrogation.
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12
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Wasserman JS, Faezov B, Patel KR, Kurimchak AN, Palacio SM, Fowle H, McEwan BC, Xu Q, Zhao Z, Cressey L, Johnson N, Duncan JS, Kettenbach AN, Dunbrack RL, Graña X. FAM122A ensures cell cycle interphase progression and checkpoint control as a SLiM-dependent substrate-competitive inhibitor to the B55⍺/PP2A phosphatase. bioRxiv 2023:2023.03.06.531310. [PMID: 36945596 PMCID: PMC10028791 DOI: 10.1101/2023.03.06.531310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The Ser/Thr protein phosphatase 2A (PP2A) is a highly conserved collection of heterotrimeric holoenzymes responsible for the dephosphorylation of many regulated phosphoproteins. Substrate recognition and the integration of regulatory cues are mediated by B regulatory subunits that are complexed to the catalytic subunit (C) by a scaffold protein (A). PP2A/B55 substrate recruitment was thought to be mediated by charge-charge interactions between the surface of B55α and its substrates. Challenging this view, we recently discovered a conserved SLiM [ RK ]- V -x-x-[ VI ]- R in a range of proteins, including substrates such as the retinoblastoma-related protein p107 and TAU (Fowle et al. eLife 2021;10:e63181). Here we report the identification of this SLiM in FAM122A, an inhibitor of B55α/PP2A. This conserved SLiM is necessary for FAM122A binding to B55α in vitro and in cells. Computational structure prediction with AlphaFold2 predicts an interaction consistent with the mutational and biochemical data and supports a mechanism whereby FAM122A uses the 'SLiM' in the form of a short α-helix to dock to the B55α top groove. In this model, FAM122A spatially constrains substrate access by occluding the catalytic subunit with a second α-helix immediately adjacent to helix 1. Consistently, FAM122A functions as a competitive inhibitor as it prevents binding of substrates in in vitro competition assays and the dephosphorylation of CDK substrates by B55α/PP2A in cell lysates. Ablation of FAM122A in human cell lines reduces the rate of proliferation, progression through cell cycle transitions and abrogates G1/S and intra-S phase cell cycle checkpoints. FAM122A-KO in HEK293 cells results in attenuation of CHK1 and CHK2 activation in response to replication stress. Overall, these data strongly suggest that FAM122A is a 'SLiM'-dependent, substrate-competitive inhibitor of B55α/PP2A that suppresses multiple functions of B55α in the DNA damage response and in timely progression through the cell cycle interphase.
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13
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Brauer BL, Wiredu K, Gerber SA, Kettenbach AN. Evaluation of Quantification and Normalization Strategies for Phosphoprotein Phosphatase Affinity Proteomics: Application to Breast Cancer Signaling. J Proteome Res 2023; 22:47-61. [PMID: 36448918 PMCID: PMC10625046 DOI: 10.1021/acs.jproteome.2c00465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Accurate quantification of proteomics data is essential for revealing and understanding biological signaling processes. We have recently developed a chemical proteomic strategy termed phosphatase inhibitor beads and mass spectrometry (PIB-MS) to investigate endogenous phosphoprotein phosphatase (PPP) dephosphorylation signaling. Here, we compare the robustness and reproducibility of status quo quantification methods for optimal performance and ease of implementation. We then apply PIB-MS to an array of breast cancer cell lines to determine differences in PPP signaling between subtypes. Breast cancer, a leading cause of cancer death in women, consists of three main subtypes: estrogen receptor-positive (ER+), human epidermal growth factor receptor two positive (HER2+), and triple-negative (TNBC). Although there are effective treatment strategies for ER+ and HER2+ subtypes, tumors become resistant and progress. Furthermore, TNBC has few targeted therapies. Therefore, there is a need to identify new approaches for treating breast cancers. Using PIB-MS, we distinguished TNBC from non-TNBC based on subtype-specific PPP holoenzyme composition. In addition, we identified an increase in PPP interactions with Hippo pathway proteins in TNBC. These interactions suggest that phosphatases in TNBC play an inhibitory role on the Hippo pathway and correlate with increased expression of YAP/TAZ target genes both in TNBC cell lines and in TNBC patients.
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Affiliation(s)
- Brooke L. Brauer
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Kwame Wiredu
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Scott A. Gerber
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
- Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
- Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
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14
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Han KJ, Mikalayeva V, Gerber SA, Kettenbach AN, Skeberdis VA, Prekeris R. Rab40c regulates focal adhesions and PP6 activity by controlling ANKRD28 ubiquitylation. Life Sci Alliance 2022; 5:5/9/e202101346. [PMID: 35512830 PMCID: PMC9070665 DOI: 10.26508/lsa.202101346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/26/2022] [Accepted: 04/26/2022] [Indexed: 11/24/2022] Open
Abstract
Rab40c is a SOCS box-containing protein which binds Cullin5 to form a ubiquitin E3 ligase complex (Rab40c/CRL5) to regulate protein ubiquitylation. However, the exact functions of Rab40c remain to be determined, and what proteins are the targets of Rab40c-Cullin5-mediated ubiquitylation in mammalian cells are unknown. Here we showed that in migrating MDA-MB-231 cells Rab40c regulates focal adhesion's number, size, and distribution. Mechanistically, we found that Rab40c binds the protein phosphatase 6 (PP6) complex and ubiquitylates one of its subunits, ankyrin repeat domain 28 (ANKRD28), thus leading to its lysosomal degradation. Furthermore, we identified that phosphorylation of FAK and MOB1 is decreased in Rab40c knock-out cells, which may contribute to focal adhesion site regulation by Rab40c. Thus, we propose a model where Rab40c/CRL5 regulates ANKRD28 ubiquitylation and degradation, leading to a decrease in PP6 activity, which ultimately affects FAK and Hippo pathway signaling to alter focal adhesion dynamics.
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Affiliation(s)
- Ke-Jun Han
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Valeryia Mikalayeva
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Scott A Gerber
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.,Norris Cotton Cancer Center, Lebanon, NH, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.,Norris Cotton Cancer Center, Lebanon, NH, USA
| | - Vytenis A Skeberdis
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Rytis Prekeris
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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15
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Luciano AK, Korobkina E, Lyons SP, Haley JA, Fluharty S, Jung SM, Kettenbach AN, Guertin DA. Proximity labeling of endogenous RICTOR identifies mTOR Complex 2 regulation by ADP ribosylation factor ARF1. J Biol Chem 2022; 298:102379. [PMID: 35973513 PMCID: PMC9513271 DOI: 10.1016/j.jbc.2022.102379] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 07/22/2022] [Accepted: 08/09/2022] [Indexed: 01/08/2023] Open
Abstract
Mechanistic target of rapamycin (mTOR) complex 2 (mTORC2) regulates metabolism, cell proliferation, and cell survival. mTORC2 activity is stimulated by growth factors, and it phosphorylates the hydrophobic motif site of the AGC kinases AKT, SGK, and PKC. However, the proteins that interact with mTORC2 to control its activity and localization remain poorly defined. To identify mTORC2-interacting proteins in living cells, we tagged endogenous RICTOR, an essential mTORC2 subunit, with the modified BirA biotin ligase BioID2 and performed live-cell proximity labeling. We identified 215 RICTOR-proximal proteins, including proteins with known mTORC2 pathway interactions, and 135 proteins (63%) not previously linked to mTORC2 signaling, including nuclear and cytoplasmic proteins. Our imaging and cell fractionation experiments suggest nearly 30% of RICTOR is in the nucleus, hinting at potential nuclear functions. We also identified 29 interactors containing RICTOR-dependent, insulin-stimulated phosphorylation sites, thus providing insight into mTORC2-dependent insulin signaling dynamics. Finally, we identify the endogenous ADP ribosylation factor 1 (ARF1) GTPase as an mTORC2-interacting protein. Through gain-of-function and loss-of-function studies, we provide functional evidence that ARF1 may negatively regulate mTORC2. In summary, we present a new method of studying endogenous mTORC2, a resource of RICTOR/mTORC2 protein interactions in living cells, and a potential mechanism of mTORC2 regulation by the ARF1 GTPase.
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Affiliation(s)
- Amelia K Luciano
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Ekaterina Korobkina
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Scott P Lyons
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - John A Haley
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Shelagh Fluharty
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Su Myung Jung
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755; Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - David A Guertin
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605; Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605.
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16
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Smolen KA, Kettenbach AN. A Mass Spectrometry-Based Approach to Identify Phosphoprotein Phosphatases and their Interactors. J Vis Exp 2022. [DOI: 10.3791/63805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
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17
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Kage F, Vicente-Manzanares M, McEwan BC, Kettenbach AN, Higgs HN. Myosin II proteins are required for organization of calcium-induced actin networks upstream of mitochondrial division. Mol Biol Cell 2022; 33:ar63. [PMID: 35427150 PMCID: PMC9561854 DOI: 10.1091/mbc.e22-01-0005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The formin INF2 polymerizes a calcium-activated cytoplasmic network of actin filaments, which we refer to as calcium-induced actin polymerization (CIA). CIA plays important roles in multiple cellular processes, including mitochondrial dynamics and vesicle transport. Here, we show that nonmuscle myosin II (NMII) is activated within 60 s of calcium stimulation and rapidly recruited to the CIA network. Knockout of any individual NMII in U2OS cells affects the organization of the CIA network, as well as three downstream effects: endoplasmic-reticulum-to-mitochondrial calcium transfer, mitochondrial Drp1 recruitment, and mitochondrial division. Interestingly, while NMIIC is the least abundant NMII in U2OS cells (>200-fold less than NMIIA and >10-fold less than NMIIB), its knockout is equally deleterious to CIA. On the basis of these results, we propose that myosin II filaments containing all three NMII heavy chains exert organizational and contractile roles in the CIA network. In addition, NMIIA knockout causes a significant decrease in myosin regulatory light chain levels, which might have additional effects.
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Affiliation(s)
- Frieda Kage
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
| | - Miguel Vicente-Manzanares
- Centro de Investigacion del Cancer/Instituto de Biologia Molecular y Celular del Cancer, Centro Mixto Universidad de Salamanca, 37007 Salamanca, Spain
| | - Brennan C. McEwan
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
- Program in Cancer Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
- Program in Cancer Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
| | - Henry N. Higgs
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
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18
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Hollomon JM, Liu Z, Rusin SF, Jenkins NP, Smith AK, Koeppen K, Kettenbach AN, Myers LC, Hogan DA. The Candida albicans Cdk8-dependent phosphoproteome reveals repression of hyphal growth through a Flo8-dependent pathway. PLoS Genet 2022; 18:e1009622. [PMID: 34982775 PMCID: PMC8769334 DOI: 10.1371/journal.pgen.1009622] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 01/19/2022] [Accepted: 12/06/2021] [Indexed: 12/26/2022] Open
Abstract
Ssn3, also known as Cdk8, is a member of the four protein Cdk8 submodule within the multi-subunit Mediator complex involved in the co-regulation of transcription. In Candida albicans, the loss of Ssn3 kinase activity affects multiple phenotypes including cellular morphology, metabolism, nutrient acquisition, immune cell interactions, and drug resistance. In these studies, we generated a strain in which Ssn3 was replaced with a functional variant of Ssn3 that can be rapidly and selectively inhibited by the ATP analog 3-MB-PP1. Consistent with ssn3 null mutant and kinase dead phenotypes, inhibition of Ssn3 kinase activity promoted hypha formation. Furthermore, the increased expression of hypha-specific genes was the strongest transcriptional signal upon inhibition of Ssn3 in transcriptomics analyses. Rapid inactivation of Ssn3 was used for phosphoproteomic studies performed to identify Ssn3 kinase substrates associated with filamentation potential. Both previously validated and novel Ssn3 targets were identified. Protein phosphorylation sites that were reduced specifically upon Ssn3 inhibition included two sites in Flo8 which is a transcription factor known to positively regulate C. albicans morphology. Mutation of the two Flo8 phosphosites (threonine 589 and serine 620) was sufficient to increase Flo8-HA levels and Flo8 dependent transcriptional and morphological changes, suggesting that Ssn3 kinase activity negatively regulates Flo8.Under embedded conditions, when ssn3Δ/Δ and efg1Δ/Δ mutants were hyperfilamentous, FLO8 was essential for hypha formation. Previous work has also shown that loss of Ssn3 activity leads to increased alkalinization of medium with amino acids. Here, we show that the ssn3Δ/Δ medium alkalinization phenotype, which is dependent on STP2, a transcription factor involved in amino acid utilization, also requires FLO8 and EFG1. Together, these data show that Ssn3 activity can modulate Flo8 and its direct and indirect interactions in different ways, and underscores the potential importance of considering Ssn3 function in the control of transcription factor activities. In Candida albicans, Ssn3 kinase activity co-regulates the transcription of numerous genes involved in hyphal growth, metabolism and nutrient acquisition, immune cell interactions, and drug resistance. Using a strain in which Ssn3 could be rapidly and selectively inhibited, we identified both known and novel Ssn3 targets. We identified two phosphosites in Flo8, a regulator of morphology and virulence, that were shown to negatively regulate Flo8 levels and activity. The data and tools presented here will enable a better understanding of how Ssn3 impacts transcriptional and post-transcriptional regulation in order to coordinate processes during physiological and morphological transitions as well as during steady state growth.
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Affiliation(s)
- Jeffrey M. Hollomon
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Zhongle Liu
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Scott F. Rusin
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- Norris Cotton Cancer Center, Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, New Hampshire, United States of America
| | - Nicole P. Jenkins
- Norris Cotton Cancer Center, Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, New Hampshire, United States of America
| | - Allia K. Smith
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Katja Koeppen
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- Norris Cotton Cancer Center, Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, New Hampshire, United States of America
| | - Lawrence C. Myers
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- Department of Medical Education, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- * E-mail: (LCM); (DAH)
| | - Deborah A. Hogan
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- * E-mail: (LCM); (DAH)
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19
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Lyons SP, Greiner EC, Cressey LE, Adamo ME, Kettenbach AN. Regulation of PP2A, PP4, and PP6 holoenzyme assembly by carboxyl-terminal methylation. Sci Rep 2021; 11:23031. [PMID: 34845248 PMCID: PMC8630191 DOI: 10.1038/s41598-021-02456-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 11/15/2021] [Indexed: 12/16/2022] Open
Abstract
The family of Phosphoprotein Phosphatases (PPPs) is responsible for most cellular serine and threonine dephosphorylation. PPPs achieve substrate specificity and selectivity by forming multimeric holoenzymes. PPP holoenzyme assembly is tightly controlled, and changes in the cellular repertoire of PPPs are linked to human disease, including cancer and neurodegeneration. For PP2A, PP4, and PP6, holoenzyme formation is in part regulated by carboxyl (C)-terminal methyl-esterification (often referred to as "methylation"). Here, we use mass spectrometry-based proteomics, methylation-ablating mutations, and genome editing to elucidate the role of C-terminal methylation on PP2A, PP4, and PP6 holoenzyme assembly. We find that the catalytic subunits of PP2A, PP4, and PP6 are frequently methylated in cancer cells and that deletion of the C-terminal leucine faithfully recapitulates loss of methylation. We observe that loss of PP2A methylation consistently reduced B55, B56, and B72 regulatory subunit binding in cancer and non-transformed cell lines. However, Striatin subunit binding is only affected in non-transformed cells. For PP4, we find that PP4R1 and PP4R3β bind in a methylation-dependent manner. Intriguingly, loss of methylation does not affect PP6 holoenzymes. Our analyses demonstrate in an unbiased, comprehensive, and isoform-specific manner the crucial regulatory function of endogenous PPP methylation in transformed and non-transformed cell lines.
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Affiliation(s)
- Scott P Lyons
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | | | | | | | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
- Norris Cotton Cancer Center, Lebanon, NH, USA.
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20
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Fowle H, Zhao Z, Xu Q, Wasserman JS, Wang X, Adeyemi M, Feiser F, Kurimchak AN, Atar D, McEwan BC, Kettenbach AN, Page R, Peti W, Dunbrack RL, Graña X. PP2A/B55α substrate recruitment as defined by the retinoblastoma-related protein p107. eLife 2021; 10:63181. [PMID: 34661528 PMCID: PMC8575462 DOI: 10.7554/elife.63181] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 10/17/2021] [Indexed: 12/23/2022] Open
Abstract
Protein phosphorylation is a reversible post-translation modification essential in cell signaling. This study addresses a long-standing question as to how the most abundant serine/threonine protein phosphatase 2 (PP2A) holoenzyme, PP2A/B55α, specifically recognizes substrates and presents them to the enzyme active site. Here, we show how the PP2A regulatory subunit B55α recruits p107, a pRB-related tumor suppressor and B55α substrate. Using molecular and cellular approaches, we identified a conserved region 1 (R1, residues 615–626) encompassing the strongest p107 binding site. This enabled us to identify an ‘HxRVxxV619-625’ short linear motif (SLiM) in p107 as necessary for B55α binding and dephosphorylation of the proximal pSer-615 in vitro and in cells. Numerous B55α/PP2A substrates, including TAU, contain a related SLiM C-terminal from a proximal phosphosite, ‘p[ST]-P-x(4,10)-[RK]-V-x-x-[VI]-R.’ Mutation of conserved SLiM residues in TAU dramatically inhibits dephosphorylation by PP2A/B55α, validating its generality. A data-guided computational model details the interaction of residues from the conserved p107 SLiM, the B55α groove, and phosphosite presentation. Altogether, these data provide key insights into PP2A/B55α’s mechanisms of substrate recruitment and active site engagement, and also facilitate identification and validation of new substrates, a key step towards understanding PP2A/B55α’s role in multiple cellular processes.
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Affiliation(s)
- Holly Fowle
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
| | - Ziran Zhao
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
| | - Qifang Xu
- Fels Institute for Cancer Research and Molecular Biology, Temple University Lewis Katz School of Medicine, Philadelphia, United States
| | - Jason S Wasserman
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
| | - Xinru Wang
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, United States
| | - Mary Adeyemi
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
| | - Felicity Feiser
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
| | - Alison N Kurimchak
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
| | - Diba Atar
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
| | - Brennan C McEwan
- Department of Biochemistry and Cell Biology, Hitchcock Medical Center at Dartmouth, Lebanon, United States
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Hitchcock Medical Center at Dartmouth, Lebanon, United States
| | - Rebecca Page
- Department Cell Biology, UConn Health, Farmington, United States
| | - Wolfgang Peti
- Department Molecular Biology and Biophysics, UConn Health, Farmington, United States
| | - Roland L Dunbrack
- Fels Institute for Cancer Research and Molecular Biology, Temple University Lewis Katz School of Medicine, Philadelphia, United States
| | - Xavier Graña
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, United States
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21
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Brauer BL, Wiredu K, Mitchell S, Moorhead GB, Gerber SA, Kettenbach AN. Affinity-based profiling of endogenous phosphoprotein phosphatases by mass spectrometry. Nat Protoc 2021; 16:4919-4943. [PMID: 34518704 PMCID: PMC8822503 DOI: 10.1038/s41596-021-00604-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 07/12/2021] [Indexed: 02/08/2023]
Abstract
Phosphoprotein phosphatases (PPPs) execute >90% of serine/threonine dephosphorylation in cells and tissues. While the role of PPPs in cell biology and diseases such as cancer, cardiac hypertrophy and Alzheimer's disease is well established, the molecular mechanisms governing and governed by PPPs still await discovery. Here we describe a chemical proteomic strategy, phosphatase inhibitor beads and mass spectrometry (PIB-MS), that enables the identification and quantification of PPPs and their posttranslational modifications in as little as 12 h. Using a specific but nonselective PPP inhibitor immobilized on beads, PIB-MS enables the efficient affinity-capture, identification and quantification of endogenous PPPs and associated proteins ('PPPome') from cells and tissues. PIB-MS captures functional, endogenous PPP subunit interactions and enables discovery of new binding partners. It performs PPP enrichment without exogenous expression of tagged proteins or specific antibodies. Because PPPs are among the most conserved proteins across evolution, PIB-MS can be employed in any cell line, tissue or organism.
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Affiliation(s)
- Brooke L. Brauer
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Kwame Wiredu
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Sierra Mitchell
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, T2N 1N4, Canada
| | - Greg B. Moorhead
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, T2N 1N4, Canada
| | - Scott A. Gerber
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA,Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA,Correspondence: , Phone: 603-653-9068, Website: https://kettenbachlab.org/
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22
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Swartz SZ, Nguyen HT, McEwan BC, Adamo ME, Cheeseman IM, Kettenbach AN. Selective dephosphorylation by PP2A-B55 directs the meiosis I-meiosis II transition in oocytes. eLife 2021; 10:70588. [PMID: 34342579 PMCID: PMC8370769 DOI: 10.7554/elife.70588] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 08/02/2021] [Indexed: 12/17/2022] Open
Abstract
Meiosis is a specialized cell cycle that requires sequential changes to the cell division machinery to facilitate changing functions. To define the mechanisms that enable the oocyte-to-embryo transition, we performed time-course proteomics in synchronized sea star oocytes from prophase I through the first embryonic cleavage. Although we found that protein levels were broadly stable, our analysis reveals that dynamic waves of phosphorylation underlie each meiotic stage. We found that the phosphatase PP2A-B55 is reactivated at the meiosis I/meiosis II (MI/MII) transition, resulting in the preferential dephosphorylation of threonine residues. Selective dephosphorylation is critical for directing the MI/MII transition as altering PP2A-B55 substrate preferences disrupts key cell cycle events after MI. In addition, threonine to serine substitution of a conserved phosphorylation site in the substrate INCENP prevents its relocalization at anaphase I. Thus, through its inherent phospho-threonine preference, PP2A-B55 imposes specific phosphoregulated behaviors that distinguish the two meiotic divisions.
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Affiliation(s)
- S Zachary Swartz
- Whitehead Institute for Biomedical Research, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
| | - Hieu T Nguyen
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
| | - Brennan C McEwan
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
| | - Mark E Adamo
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, United States
| | - Iain M Cheeseman
- Whitehead Institute for Biomedical Research, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, United States
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23
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Hein JB, Garvanska DH, Nasa I, Kettenbach AN, Nilsson J. Coupling of Cdc20 inhibition and activation by BubR1. J Cell Biol 2021; 220:211939. [PMID: 33819340 PMCID: PMC8025235 DOI: 10.1083/jcb.202012081] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/18/2021] [Accepted: 02/25/2021] [Indexed: 12/25/2022] Open
Abstract
Tight regulation of the APC/C-Cdc20 ubiquitin ligase that targets cyclin B1 for degradation is important for mitotic fidelity. The spindle assembly checkpoint (SAC) inhibits Cdc20 through the mitotic checkpoint complex (MCC). In addition, phosphorylation of Cdc20 by cyclin B1–Cdk1 independently inhibits APC/C–Cdc20 activation. This creates a conundrum for how Cdc20 is activated before cyclin B1 degradation. Here, we show that the MCC component BubR1 harbors both Cdc20 inhibition and activation activities, allowing for cross-talk between the two Cdc20 inhibition pathways. Specifically, BubR1 acts as a substrate specifier for PP2A-B56 to enable efficient Cdc20 dephosphorylation in the MCC. A mutant Cdc20 mimicking the dephosphorylated state escapes a mitotic checkpoint arrest, arguing that restricting Cdc20 dephosphorylation to the MCC is important. Collectively, our work reveals how Cdc20 can be dephosphorylated in the presence of cyclin B1-Cdk1 activity without causing premature anaphase onset.
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Affiliation(s)
- Jamin B Hein
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Science, Copenhagen, Denmark
| | - Dimitriya H Garvanska
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Science, Copenhagen, Denmark
| | - Isha Nasa
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH
| | - Arminja N Kettenbach
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH
| | - Jakob Nilsson
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Science, Copenhagen, Denmark
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24
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Magliozzi JO, Sears J, Cressey L, Brady M, Opalko HE, Kettenbach AN, Moseley JB. Fission yeast Pak1 phosphorylates anillin-like Mid1 for spatial control of cytokinesis. J Cell Biol 2021; 219:151784. [PMID: 32421151 PMCID: PMC7401808 DOI: 10.1083/jcb.201908017] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 03/09/2020] [Accepted: 04/28/2020] [Indexed: 12/17/2022] Open
Abstract
Protein kinases direct polarized growth by regulating the cytoskeleton in time and space and could play similar roles in cell division. We found that the Cdc42-activated polarity kinase Pak1 colocalizes with the assembling contractile actomyosin ring (CAR) and remains at the division site during septation. Mutations in pak1 led to defects in CAR assembly and genetic interactions with cytokinesis mutants. Through a phosphoproteomic screen, we identified novel Pak1 substrates that function in polarized growth and cytokinesis. For cytokinesis, we found that Pak1 regulates the localization of its substrates Mid1 and Cdc15 to the CAR. Mechanistically, Pak1 phosphorylates the Mid1 N-terminus to promote its association with cortical nodes that act as CAR precursors. Defects in Pak1-Mid1 signaling lead to misplaced and defective division planes, but these phenotypes can be rescued by synthetic tethering of Mid1 to cortical nodes. Our work defines a new signaling mechanism driven by a cell polarity kinase that promotes CAR assembly in the correct time and place.
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Affiliation(s)
- Joseph O Magliozzi
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Jack Sears
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH.,Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Lauren Cressey
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH.,Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Marielle Brady
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Hannah E Opalko
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH.,Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - James B Moseley
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH
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25
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Papke CM, Smolen KA, Swingle MR, Cressey L, Heng RA, Toporsian M, Deng L, Hagen J, Shen Y, Chung WK, Kettenbach AN, Honkanen RE. A disorder-related variant (E420K) of a PP2A-regulatory subunit (PPP2R5D) causes constitutively active AKT-mTOR signaling and uncoordinated cell growth. J Biol Chem 2021; 296:100313. [PMID: 33482199 PMCID: PMC7952134 DOI: 10.1016/j.jbc.2021.100313] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 01/13/2021] [Accepted: 01/15/2021] [Indexed: 02/08/2023] Open
Abstract
Functional genomic approaches have facilitated the discovery of rare genetic disorders and improved efforts to decipher their underlying etiology. PPP2R5D-related disorder is an early childhood onset condition characterized by intellectual disability, hypotonia, autism-spectrum disorder, macrocephaly, and dysmorphic features. The disorder is caused by de novo single nucleotide changes in PPP2R5D, which generate heterozygous dominant missense variants. PPP2R5D is known to encode a B'-type (B'56δ) regulatory subunit of a PP2A-serine/threonine phosphatase. To help elucidate the molecular mechanisms altered in PPP2R5D-related disorder, we used a CRISPR-single-base editor to generate HEK-293 cells in which a single transition (c.1258G>A) was introduced into one allele, precisely recapitulating a clinically relevant E420K variant. Unbiased quantitative proteomic and phosphoproteomic analyses of endogenously expressed proteins revealed heterozygous-dominant changes in kinase/phosphatase signaling. These data combined with orthogonal validation studies revealed a previously unrecognized interaction of PPP2R5D with AKT in human cells, leading to constitutively active AKT-mTOR signaling, increased cell size, and uncoordinated cellular growth in E420K-variant cells. Rapamycin reduced cell size and dose-dependently reduced RPS6 phosphorylation in E420K-variant cells, suggesting that inhibition of mTOR1 can suppress both the observed RPS6 hyperphosphorylation and increased cell size. Together, our findings provide a deeper understanding of PPP2R5D and insight into how the E420K-variant alters signaling networks influenced by PPP2R5D. Our comprehensive approach, which combines precise genome editing, isobaric tandem mass tag labeling of peptides generated from endogenously expressed proteins, and concurrent liquid chromatography-mass spectrometry (LC-MS3), also provides a roadmap that can be used to rapidly explore the etiologies of additional genetic disorders.
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Affiliation(s)
- Cinta M Papke
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Kali A Smolen
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - Mark R Swingle
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Lauren Cressey
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - Richard A Heng
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Mourad Toporsian
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
| | - Liyong Deng
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Jacob Hagen
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Yufeng Shen
- Department of Systems Biology, Columbia University Irving Medical Center, New York, New York, USA
| | - Wendy K Chung
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA; Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, New York, USA; Department of Medicine, Columbia University Medical Center, New York, New York, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA; Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA.
| | - Richard E Honkanen
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA.
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26
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Ohnstad AE, Delgado JM, North BJ, Nasa I, Kettenbach AN, Schultz SW, Shoemaker CJ. Receptor-mediated clustering of FIP200 bypasses the role of LC3 lipidation in autophagy. EMBO J 2020; 39:e104948. [PMID: 33226137 PMCID: PMC7737610 DOI: 10.15252/embj.2020104948] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 09/10/2020] [Accepted: 09/17/2020] [Indexed: 12/22/2022] Open
Abstract
Autophagosome formation requires multiple autophagy-related (ATG) factors. However, we find that a subset of autophagy substrates remains robustly targeted to the lysosome in the absence of several core ATGs, including the LC3 lipidation machinery. To address this unexpected result, we performed genome-wide CRISPR screens identifying genes required for NBR1 flux in ATG7KO cells. We find that ATG7-independent autophagy still requires canonical ATG factors including FIP200. However, in the absence of LC3 lipidation, additional factors are required including TAX1BP1 and TBK1. TAX1BP1's ability to cluster FIP200 around NBR1 cargo and induce local autophagosome formation enforces cargo specificity and replaces the requirement for lipidated LC3. In support of this model, we define a ubiquitin-independent mode of TAX1BP1 recruitment to NBR1 puncta, highlighting that TAX1BP1 recruitment and clustering, rather than ubiquitin binding per se, is critical for function. Collectively, our data provide a mechanistic basis for reports of selective autophagy in cells lacking the lipidation machinery, wherein receptor-mediated clustering of upstream autophagy factors drives continued autophagosome formation.
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Affiliation(s)
- Amelia E Ohnstad
- Department of Biochemistry and Cell BiologyGeisel School of Medicine at DartmouthHanoverNHUSA
| | - Jose M Delgado
- Department of Biochemistry and Cell BiologyGeisel School of Medicine at DartmouthHanoverNHUSA
| | - Brian J North
- Department of Biochemistry and Cell BiologyGeisel School of Medicine at DartmouthHanoverNHUSA
| | - Isha Nasa
- Department of Biochemistry and Cell BiologyGeisel School of Medicine at DartmouthHanoverNHUSA
- Norris Cotton Cancer CenterLebanonNHUSA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell BiologyGeisel School of Medicine at DartmouthHanoverNHUSA
- Norris Cotton Cancer CenterLebanonNHUSA
| | - Sebastian W Schultz
- Centre for Cancer Cell ReprogrammingFaculty of MedicineUniversity of OsloOsloNorway
- Department of Molecular Cell BiologyInstitute for Cancer ResearchOslo University HospitalOsloNorway
| | - Christopher J Shoemaker
- Department of Biochemistry and Cell BiologyGeisel School of Medicine at DartmouthHanoverNHUSA
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27
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Nasa I, Kettenbach AN. Effects of carboxyl-terminal methylation on holoenzyme function of the PP2A subfamily. Biochem Soc Trans 2020; 48:2015-2027. [PMID: 33125487 PMCID: PMC8380034 DOI: 10.1042/bst20200177] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/14/2020] [Accepted: 09/16/2020] [Indexed: 01/07/2023]
Abstract
Phosphoprotein Phosphatases (PPPs) are enzymes highly conserved from yeast and human and catalyze the majority of the serine and threonine dephosphorylation in cells. To achieve substrate specificity and selectivity, PPPs form multimeric holoenzymes consisting of catalytic, structural/scaffolding, and regulatory subunits. For the Protein Phosphatase 2A (PP2A)-subfamily of PPPs, holoenzyme assembly is at least in part regulated by an unusual carboxyl-terminal methyl-esterification, commonly referred to as 'methylation'. Carboxyl-terminal methylation is catalyzed by Leucine carboxyl methyltransferase-1 (LCMT1) that utilizes S-adenosyl-methionine (SAM) as the methyl donor and removed by protein phosphatase methylesterase 1 (PME1). For PP2A, methylation dictates regulatory subunit selection and thereby downstream phosphorylation signaling. Intriguingly, there are four families of PP2A regulatory subunits, each exhibiting different levels of methylation sensitivity. Thus, changes in PP2A methylation stoichiometry alters the complement of PP2A holoenzymes in cells and creates distinct modes of kinase opposition. Importantly, selective inactivation of PP2A signaling through the deregulation of methylation is observed in several diseases, most prominently Alzheimer's disease (AD). In this review, we focus on how carboxyl-terminal methylation of the PP2A subfamily (PP2A, PP4, and PP6) regulates holoenzyme function and thereby phosphorylation signaling, with an emphasis on AD.
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Affiliation(s)
- Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, U.S.A
- Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH, U.S.A
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, U.S.A
- Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH, U.S.A
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28
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Nasa I, Cressey LE, Kruse T, Hertz EPT, Gui J, Graves LM, Nilsson J, Kettenbach AN. Quantitative kinase and phosphatase profiling reveal that CDK1 phosphorylates PP2Ac to promote mitotic entry. Sci Signal 2020; 13:13/648/eaba7823. [PMID: 32900880 DOI: 10.1126/scisignal.aba7823] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The reciprocal regulation of phosphoprotein phosphatases (PPPs) by protein kinases is essential to cell cycle progression and control, particularly during mitosis for which the role of kinases has been extensively studied. PPPs perform much of the serine/threonine dephosphorylation in eukaryotic cells and achieve substrate selectivity and specificity through the interaction of distinct regulatory subunits with conserved catalytic subunits in holoenzyme complexes. Using a mass spectrometry-based chemical proteomics approach to enrich, identify, and quantify endogenous PPP holoenzyme complexes combined with kinase profiling, we investigated the phosphorylation-dependent regulation of PPP holoenzymes in mitotic cells. We found that cyclin-dependent kinase 1 (CDK1) phosphorylated a threonine residue on the catalytic subunit of the phosphatase PP2A, which disrupted its holoenzyme formation with the regulatory subunit B55. The consequent decrease in the dephosphorylation of PP2A-B55 substrates promoted mitotic entry. This direct phosphorylation by CDK1 was in addition to a previously reported indirect mechanism, thus adding a layer to the interaction between CDK1 and PP2A in regulating mitotic entry.
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Affiliation(s)
- Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH 03755, USA.,Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH 03766, USA
| | - Lauren E Cressey
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH 03755, USA
| | - Thomas Kruse
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Emil P T Hertz
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Jiang Gui
- Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth College, Lebanon, NH 03756, USA
| | - Lee M Graves
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Jakob Nilsson
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH 03755, USA. .,Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH 03766, USA
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29
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Douglas P, Ye R, Radhamani S, Cobban A, Jenkins NP, Bartlett E, Roveredo J, Kettenbach AN, Lees-Miller SP. Nocodazole-Induced Expression and Phosphorylation of Anillin and Other Mitotic Proteins Are Decreased in DNA-Dependent Protein Kinase Catalytic Subunit-Deficient Cells and Rescued by Inhibition of the Anaphase-Promoting Complex/Cyclosome with proTAME but Not Apcin. Mol Cell Biol 2020; 40:e00191-19. [PMID: 32284347 PMCID: PMC7296215 DOI: 10.1128/mcb.00191-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 05/15/2019] [Accepted: 03/31/2020] [Indexed: 11/23/2022] Open
Abstract
The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) has well-established roles in DNA double-strand break repair, and recently, nonrepair functions have also been reported. To better understand its cellular functions, we deleted DNA-PKcs from HeLa and A549 cells using CRISPR/Cas9. The resulting cells were radiation sensitive, had reduced expression of ataxia-telangiectasia mutated (ATM), and exhibited multiple mitotic defects. Mechanistically, nocodazole-induced upregulation of cyclin B1, anillin, and securin was decreased in DNA-PKcs-deficient cells, as were phosphorylation of Aurora A on threonine 288, phosphorylation of Polo-like kinase 1 (PLK1) on threonine 210, and phosphorylation of targeting protein for Xenopus Klp2 (TPX2) on serine 121. Moreover, reduced nocodazole-induced expression of anillin, securin, and cyclin B1 and phosphorylation of PLK1, Aurora A, and TPX2 were rescued by inhibition of the anaphase-promoting complex/cyclosome (APC/C) by proTAME, which prevents binding of the APC/C-activating proteins Cdc20 and Cdh1 to the APC/C. Altogether, our studies suggest that loss of DNA-PKcs prevents inactivation of the APC/C in nocodazole-treated cells.
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Affiliation(s)
- Pauline Douglas
- Department of Biochemistry and Molecular Biology and Robson DNA Science Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ruiqiong Ye
- Department of Biochemistry and Molecular Biology and Robson DNA Science Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Suraj Radhamani
- Department of Biochemistry and Molecular Biology and Robson DNA Science Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Alexander Cobban
- Department of Biochemistry and Molecular Biology and Robson DNA Science Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Nicole P Jenkins
- Norris Cotton Cancer Center, Geisel School of Medicine, Lebanon Campus at Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA
| | - Edward Bartlett
- Department of Biochemistry and Molecular Biology and Robson DNA Science Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan Roveredo
- Department of Biochemistry and Molecular Biology and Robson DNA Science Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Arminja N Kettenbach
- Norris Cotton Cancer Center, Geisel School of Medicine, Lebanon Campus at Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA
| | - Susan P Lees-Miller
- Department of Biochemistry and Molecular Biology and Robson DNA Science Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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30
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Kruse T, Gnosa SP, Nasa I, Garvanska DH, Hein JB, Nguyen H, Samsøe-Petersen J, Lopez-Mendez B, Hertz EPT, Schwarz J, Pena HS, Nikodemus D, Kveiborg M, Kettenbach AN, Nilsson J. Mechanisms of site-specific dephosphorylation and kinase opposition imposed by PP2A regulatory subunits. EMBO J 2020; 39:e103695. [PMID: 32400009 PMCID: PMC7327492 DOI: 10.15252/embj.2019103695] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 04/03/2020] [Accepted: 04/21/2020] [Indexed: 12/11/2022] Open
Abstract
PP2A is an essential protein phosphatase that regulates most cellular processes through the formation of holoenzymes containing distinct regulatory B‐subunits. Only a limited number of PP2A‐regulated phosphorylation sites are known. This hampers our understanding of the mechanisms of site‐specific dephosphorylation and of its tumor suppressor functions. Here, we develop phosphoproteomic strategies for global substrate identification of PP2A‐B56 and PP2A‐B55 holoenzymes. Strikingly, we find that B‐subunits directly affect the dephosphorylation site preference of the PP2A catalytic subunit, resulting in unique patterns of kinase opposition. For PP2A‐B56, these patterns are further modulated by affinity and position of B56 binding motifs. Our screens identify phosphorylation sites in the cancer target ADAM17 that are regulated through a conserved B56 binding site. Binding of PP2A‐B56 to ADAM17 protease decreases growth factor signaling and tumor development in mice. This work provides a roadmap for the identification of phosphatase substrates and reveals unexpected mechanisms governing PP2A dephosphorylation site specificity and tumor suppressor function.
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Affiliation(s)
- Thomas Kruse
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sebastian Peter Gnosa
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Isha Nasa
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA.,Norris Cotton Cancer Center, Lebanon, NH, USA
| | - Dimitriya Hristoforova Garvanska
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jamin B Hein
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hieu Nguyen
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA.,Norris Cotton Cancer Center, Lebanon, NH, USA
| | - Jacob Samsøe-Petersen
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Blanca Lopez-Mendez
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Emil Peter Thrane Hertz
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jeanette Schwarz
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Hanna Sofia Pena
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Denise Nikodemus
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Marie Kveiborg
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Arminja N Kettenbach
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA.,Norris Cotton Cancer Center, Lebanon, NH, USA
| | - Jakob Nilsson
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Caudron-Herger M, Wassmer E, Nasa I, Schultz AS, Seiler J, Kettenbach AN, Diederichs S. Identification, quantification and bioinformatic analysis of RNA-dependent proteins by RNase treatment and density gradient ultracentrifugation using R-DeeP. Nat Protoc 2020; 15:1338-1370. [PMID: 32094787 PMCID: PMC7212772 DOI: 10.1038/s41596-019-0261-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 10/29/2019] [Indexed: 12/14/2022]
Abstract
Analysis of RNA-protein complexes is central to understanding the molecular circuitry governing cellular processes. In recent years, several proteome-wide studies have been dedicated to the identification of RNA-binding proteins. Here, we describe in detail R-DeeP, an approach built on RNA dependence, defined as the ability of a protein to engage in protein complexes only in the presence of RNA, involving direct or indirect interaction with RNA. This approach provides-for the first time, to our knowledge-quantitative information on the fraction of a protein associated with RNA-protein complexes. R-DeeP is independent of any potentially biased purification procedures. It is based on cellular lysate fractionation by density gradient ultracentrifugation and subsequent analysis by proteome-wide mass spectrometry (MS) or individual western blotting. The comparison of lysates with and without previous RNase treatment enables the identification of differences in the apparent molecular weight and, hence, the size of the complexes. In combination with information from databases of protein-protein complexes, R-DeeP facilitates the computational reconstruction of protein complexes from proteins migrating in the same fraction. In addition, we developed a pipeline for the statistical analysis of the MS dataset to automatically identify RNA-dependent proteins (proteins whose interactome depends on RNA). With this protocol, the individual analysis of proteins of interest by western blotting can be completed within 1-2 weeks. For proteome-wide studies, additional time is needed for the integration of the proteomic and statistical analyses. In the future, R-DeeP can be extended to other fractionation techniques, such as chromatography.
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Affiliation(s)
- Maiwen Caudron-Herger
- Division of RNA Biology & Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Elsa Wassmer
- Division of RNA Biology & Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Astrid-Solveig Schultz
- Division of Cancer Research, Department of Thoracic Surgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK)-Partner Site Freiburg, Freiburg, Germany
| | - Jeanette Seiler
- Division of RNA Biology & Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Sven Diederichs
- Division of RNA Biology & Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany.
- Division of Cancer Research, Department of Thoracic Surgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK)-Partner Site Freiburg, Freiburg, Germany.
- National Center for Tumor Diseases (NCT)-Partner Site Heidelberg, Heidelberg, Germany.
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Wang X, Garvanska DH, Nasa I, Ueki Y, Zhang G, Kettenbach AN, Peti W, Nilsson J, Page R. A dynamic charge-charge interaction modulates PP2A:B56 substrate recruitment. eLife 2020; 9:55966. [PMID: 32195664 PMCID: PMC7108865 DOI: 10.7554/elife.55966] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 03/14/2020] [Indexed: 12/16/2022] Open
Abstract
The recruitment of substrates by the ser/thr protein phosphatase 2A (PP2A) is poorly understood, limiting our understanding of PP2A-regulated signaling. Recently, the first PP2A:B56 consensus binding motif, LxxIxE, was identified. However, most validated LxxIxE motifs bind PP2A:B56 with micromolar affinities, suggesting that additional motifs exist to enhance PP2A:B56 binding. Here, we report the requirement of a positively charged motif in a subset of PP2A:B56 interactors, including KIF4A, to facilitate B56 binding via dynamic, electrostatic interactions. Using molecular and cellular experiments, we show that a conserved, negatively charged groove on B56 mediates dynamic binding. We also discovered that this positively charged motif, in addition to facilitating KIF4A dephosphorylation, is essential for condensin I binding, a function distinct and exclusive from PP2A-B56 binding. Together, these results reveal how dynamic, charge-charge interactions fine-tune the interactions mediated by specific motifs, providing a new framework for understanding how PP2A regulation drives cellular signaling.
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Affiliation(s)
- Xinru Wang
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, United States
| | - Dimitriya H Garvanska
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
| | - Yumi Ueki
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gang Zhang
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Medical Center Drive, Lebanon, United States
| | - Wolfgang Peti
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, United States
| | - Jakob Nilsson
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rebecca Page
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, United States
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Brauer BL, Moon TM, Sheftic SR, Nasa I, Page R, Peti W, Kettenbach AN. Leveraging New Definitions of the LxVP SLiM To Discover Novel Calcineurin Regulators and Substrates. ACS Chem Biol 2019; 14:2672-2682. [PMID: 31633908 PMCID: PMC6925343 DOI: 10.1021/acschembio.9b00606] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The Phosphoprotein Phosphatase Calcineurin (CN, PP2B, PP3) recognizes and binds to two short linear motifs (SLiMs), PxIxIT and LxVP, in its regulators and substrates. These interactions enable CN function in many key biological processes. The identification of SLiMs is difficult because of their short, degenerate sequence and often low binding affinity. Here we combine Structure Based Shape Complementarity (SBSC) analysis and proteome-wide affinity purification-mass spectrometry to identify PxIxIT and LxVP containing CN interactors to expand and thereby redefine the LxVP motif. We find that the new πφ-LxVx primary sequence defines an ensemble of binding competent confirmations and thus the binding on-rate, making it difficult to predict the LxVP binding strength from its sequence. Our analysis confirms existing and, more importantly, identifies novel CN interactors, substrates, and thus biological functions of CN.
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Affiliation(s)
- Brooke L. Brauer
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - Thomas M. Moon
- Department of Chemistry and Biochemistry, University of Arizona, 1041 E. Lowell Street, Tucson, Arizona 85721, United States
| | - Sarah R. Sheftic
- Department of Chemistry and Biochemistry, University of Arizona, 1041 E. Lowell Street, Tucson, Arizona 85721, United States
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - Rebecca Page
- Department of Chemistry and Biochemistry, University of Arizona, 1041 E. Lowell Street, Tucson, Arizona 85721, United States
| | - Wolfgang Peti
- Department of Chemistry and Biochemistry, University of Arizona, 1041 E. Lowell Street, Tucson, Arizona 85721, United States
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756, United States
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Abstract
To enter into mitosis, cells must shut off the cell cycle inhibitor Wee1. SAD family protein kinases regulate Wee1 signaling in yeast and humans. In Schizosaccharomyces pombe, two SAD kinases (Cdr1/Nim1 and Cdr2) act as upstream inhibitors of Wee1. Previous studies found that S. pombe Cdr1/Nim1 directly phosphorylates and inhibits Wee1 in vitro, but different results were obtained for budding yeast and human SAD kinases. Without a full understanding of Cdr1 action on Wee1, it has been difficult to assess the in vivo relevance and conservation of this mechanism. Here, we show that both Cdr1 and Cdr2 promote Wee1 phosphorylation in cells, but only Cdr1 inhibits Wee1 kinase activity. Inhibition occurs when Cdr1 phosphorylates a cluster of serine residues linking α-helices G and H of the Wee1 kinase domain. This region is highly divergent among different Wee1 proteins, consistent with distinct regulatory mechanisms. A wee(4A) mutant that impairs phosphorylation by Cdr1 delays mitotic entry and causes elongated cells. By disrupting and retargeting Cdr1 localization, we show that Cdr1 inhibition of Wee1 occurs in cells at cortical nodes formed by Cdr2. On the basis of our results, we propose a two-step model for inhibition of Wee1 by Cdr1 and Cdr2 at nodes.
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Affiliation(s)
- Hannah E Opalko
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755.,Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755.,Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
| | - James B Moseley
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755
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Shee K, Wells JD, Ung M, Hampsch RA, Traphagen NA, Yang W, Liu SC, Zeldenrust MA, Wang L, Kalari KR, Yu J, Boughey JC, Demidenko E, Kettenbach AN, Cheng C, Goetz MP, Miller TW. A Transcriptionally Definable Subgroup of Triple-Negative Breast and Ovarian Cancer Samples Shows Sensitivity to HSP90 Inhibition. Clin Cancer Res 2019; 26:159-170. [PMID: 31558472 DOI: 10.1158/1078-0432.ccr-18-2213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 08/05/2019] [Accepted: 09/23/2019] [Indexed: 02/06/2023]
Abstract
PURPOSE We hypothesized that integrated analysis of cancer types from different lineages would reveal novel molecularly defined subgroups with unique therapeutic vulnerabilities. On the basis of the molecular similarities between subgroups of breast and ovarian cancers, we analyzed these cancers as a single cohort to test our hypothesis. EXPERIMENTAL DESIGN Identification of transcriptional subgroups of cancers and drug sensitivity analyses were performed using mined data. Cell line sensitivity to Hsp90 inhibitors (Hsp90i) was tested in vitro. The ability of a transcriptional signature to predict Hsp90i sensitivity was validated using cell lines, and cell line- and patient-derived xenograft (PDX) models. Mechanisms of Hsp90i sensitivity were uncovered using immunoblot and RNAi. RESULTS Transcriptomic analyses of breast and ovarian cancer cell lines uncovered two mixed subgroups comprised primarily of triple-negative breast and multiple ovarian cancer subtypes. Drug sensitivity analyses revealed that cells of one mixed subgroup are significantly more sensitive to Hsp90i compared with cells from all other cancer lineages evaluated. A gene expression classifier was generated that predicted Hsp90i sensitivity in vitro, and in cell line- and PDXs. Cells from the Hsp90i-sensitive subgroup underwent apoptosis mediated by Hsp90i-induced upregulation of the proapoptotic proteins Bim and PUMA. CONCLUSIONS Our findings identify Hsp90i as a potential therapeutic strategy for a transcriptionally defined subgroup of ovarian and breast cancers. This study demonstrates that gene expression profiles may be useful to identify therapeutic vulnerabilities in tumor types with limited targetable genetic alterations, and to identify molecularly definable cancer subgroups that transcend lineage.
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Affiliation(s)
- Kevin Shee
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Jason D Wells
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Matthew Ung
- Department of Biomedical Data Sciences, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Riley A Hampsch
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Nicole A Traphagen
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Wei Yang
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Stephanie C Liu
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | | | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota
| | - Krishna R Kalari
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | - Jia Yu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota
| | - Judy C Boughey
- Department of Surgery, Mayo Clinic, Rochester, Minnesota
| | - Eugene Demidenko
- Department of Community and Family Medicine, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Arminja N Kettenbach
- Department of Biochemistry, and Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Chao Cheng
- Department of Biomedical Data Sciences, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Matthew P Goetz
- Department of Oncology, Mayo Clinic, Rochester, Minnesota.,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota
| | - Todd W Miller
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire. .,Comprehensive Breast Program, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
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36
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Hosford SR, Shee K, Wells JD, Traphagen NA, Fields JL, Hampsch RA, Kettenbach AN, Demidenko E, Miller TW. Estrogen therapy induces an unfolded protein response to drive cell death in ER+ breast cancer. Mol Oncol 2019; 13:1778-1794. [PMID: 31180176 PMCID: PMC6670014 DOI: 10.1002/1878-0261.12528] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/19/2019] [Accepted: 06/07/2019] [Indexed: 01/06/2023] Open
Abstract
Estrogens have been shown to elicit anticancer effects against estrogen receptor α (ER)-positive breast cancer. We sought to determine the mechanism underlying the therapeutic response. Response to 17β-estradiol was assessed in ER+ breast cancer models with resistance to estrogen deprivation: WHIM16 patient-derived xenografts, C7-2-HI and C4-HI murine mammary adenocarcinomas, and long-term estrogen-deprived MCF-7 cells. As another means to reactivate ER, the anti-estrogen fulvestrant was withdrawn from fulvestrant-resistant MCF-7 cells. Transcriptional, growth, apoptosis, and molecular alterations in response to ER reactivation were measured. 17β-estradiol treatment and fulvestrant withdrawal induced transcriptional activation of ER, and cells adapted to estrogen deprivation or fulvestrant were hypersensitive to 17β-estradiol. ER transcriptional response was followed by an unfolded protein response and apoptosis. Such apoptosis was dependent upon the unfolded protein response, p53, and JNK signaling. Anticancer effects were most pronounced in models exhibiting genomic amplification of the gene encoding ER (ESR1), suggesting that engagement of ER at high levels is cytotoxic. These data indicate that long-term adaptation to estrogen deprivation or ER inhibition alters sensitivity to ER reactivation. In such adapted cells, 17β-estradiol treatment and anti-estrogen withdrawal hyperactivate ER, which drives an unfolded protein response and subsequent growth inhibition and apoptosis. 17β-estradiol treatment should be considered as a therapeutic option for anti-estrogen-resistant disease, particularly in patients with tumors harboring ESR1 amplification or ER overexpression. Furthermore, therapeutic strategies that enhance an unfolded protein response may increase the therapeutic effects of ER reactivation.
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Affiliation(s)
- Sarah R Hosford
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Kevin Shee
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Jason D Wells
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Nicole A Traphagen
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Jennifer L Fields
- Department of Microbiology and Immunology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Riley A Hampsch
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Arminja N Kettenbach
- Department of Biochemistry, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Eugene Demidenko
- Department of Biomedical Data Sciences, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Todd W Miller
- Department of Molecular & Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA.,Comprehensive Breast Program, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
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Caudron-Herger M, Rusin SF, Adamo ME, Seiler J, Schmid VK, Barreau E, Kettenbach AN, Diederichs S. R-DeeP: Proteome-wide and Quantitative Identification of RNA-Dependent Proteins by Density Gradient Ultracentrifugation. Mol Cell 2019; 75:184-199.e10. [PMID: 31076284 DOI: 10.1016/j.molcel.2019.04.018] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 01/07/2019] [Accepted: 04/11/2019] [Indexed: 12/16/2022]
Abstract
The comprehensive but specific identification of RNA-binding proteins as well as the discovery of RNA-associated protein functions remain major challenges in RNA biology. Here we adapt the concept of RNA dependence, defining a protein as RNA dependent when its interactome depends on RNA. We converted this concept into a proteome-wide, unbiased, and enrichment-free screen called R-DeeP (RNA-dependent proteins), based on density gradient ultracentrifugation. Quantitative mass spectrometry identified 1,784 RNA-dependent proteins, including 537 lacking known links to RNA. Exploiting the quantitative nature of R-DeeP, proteins were classified as not, partially, or completely RNA dependent. R-DeeP identified the transcription factor CTCF as completely RNA dependent, and we uncovered that RNA is required for the CTCF-chromatin association. Additionally, R-DeeP allows reconstruction of protein complexes based on co-segregation. The whole dataset is available at http://R-DeeP.dkfz.de, providing proteome-wide, specific, and quantitative identification of proteins with RNA-dependent interactions and aiming at future functional discovery of RNA-protein complexes.
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Affiliation(s)
- Maiwen Caudron-Herger
- Division of RNA Biology and Cancer, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
| | - Scott F Rusin
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Mark E Adamo
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Jeanette Seiler
- Division of RNA Biology and Cancer, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Vera K Schmid
- Division of RNA Biology and Cancer, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Elsa Barreau
- Division of RNA Biology and Cancer, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA; Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Sven Diederichs
- Division of RNA Biology and Cancer, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; Division of Cancer Research, Department of Thoracic Surgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK)- Partner Site Freiburg, 79106 Freiburg, Germany; National Center for Tumor Diseases (NCT), Partner Site Heidelberg, Heidelberg, Germany.
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38
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A M, Fung TS, Kettenbach AN, Chakrabarti R, Higgs HN. A complex containing lysine-acetylated actin inhibits the formin INF2. Nat Cell Biol 2019; 21:592-602. [PMID: 30962575 PMCID: PMC6501848 DOI: 10.1038/s41556-019-0307-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 02/28/2019] [Indexed: 11/10/2022]
Abstract
Inverted formin 2 (INF2) is a member of the formin family of actin assembly factors. Dominant missense mutations in INF2 are linked to two diseases: focal segmental glomerulosclerosis, a kidney disease, and Charcot-Marie-Tooth disease, a neuropathy. All of the disease mutations map to the autoinhibitory diaphanous inhibitory domain. Interestingly, purified INF2 is not autoinhibited, suggesting the existence of other cellular inhibitors. Here, we purified an INF2 inhibitor from mouse brain tissue, and identified it as a complex of lysine-acetylated actin (KAc-actin) and cyclase-associated protein (CAP). Inhibition of INF2 by CAP-KAc-actin is dependent on the INF2 diaphanous inhibitory domain (DID). Treatment of CAP-KAc-actin-inhibited INF2 with histone deacetylase 6 releases INF2 inhibition, whereas inhibitors of histone deacetylase 6 block the activation of cellular INF2. Disease-associated INF2 mutants are poorly inhibited by CAP-KAc-actin, suggesting that focal segmental glomerulosclerosis and Charcot-Marie-Tooth disease result from reduced CAP-KAc-actin binding. These findings reveal a role for KAc-actin in the regulation of an actin assembly factor by a mechanism that we call facilitated autoinhibition.
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Affiliation(s)
- Mu A
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Tak Shun Fung
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Rajarshi Chakrabarti
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Henry N Higgs
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
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39
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Chen Y, Wang Y, Salas LA, Miller TW, Mark K, Marotti JD, Kettenbach AN, Cheng C, Christensen BC. Molecular and epigenetic profiles of BRCA1-like hormone-receptor-positive breast tumors identified with development and application of a copy-number-based classifier. Breast Cancer Res 2019; 21:14. [PMID: 30683142 PMCID: PMC6347811 DOI: 10.1186/s13058-018-1090-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 12/20/2018] [Indexed: 02/09/2023] Open
Abstract
Background BRCA1-mutated cancers exhibit deficient homologous recombination (HR) DNA repair, resulting in extensive copy number alterations and genome instability. HR deficiency can also arise in tumors without a BRCA1 mutation. Compared with other breast tumors, HR-deficient, BRCA1-like tumors exhibit worse prognosis but selective chemotherapeutic sensitivity. Presently, patients with triple negative breast cancer (TNBC) who do not respond to hormone endocrine-targeting therapy are given cytotoxic chemotherapy. However, more recent evidence showed a similar genomic profile between BRCA1-deficient TNBCs and hormone-receptor-positive tumors. Characterization of the somatic alterations of BRCA1-like hormone-receptor-positive breast tumors as a group, which is currently lacking, can potentially help develop biomarkers for identifying additional patients who might respond to chemotherapy. Methods We retrained and validated a copy-number-based support vector machine (SVM) classifier to identify HR-deficient, BRCA1-like breast tumors. We applied this classifier to The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) breast tumors. We assessed mutational profiles and proliferative capacity by covariate-adjusted linear models and identified differentially methylated regions using DMRcate in BRCA1-like hormone-receptor-positive tumors. Results Of the breast tumors in TCGA and METABRIC, 22% (651/2925) were BRCA1-like. Stratifying on hormone-receptor status, 13% (302/2405) receptor-positive and 69% (288/417) triple-negative tumors were BRCA1-like. Among the hormone-receptor-positive subgroup, BRCA1-like tumors showed significantly increased mutational burden and proliferative capacity (both P < 0.05). Genome-scale DNA methylation analysis of BRCA1-like tumors identified 202 differentially methylated gene regions, including hypermethylated BRCA1. Individually significant CpGs were enriched for enhancer regions (P < 0.05). The hypermethylated gene sets were enriched for DNA and chromatin conformation (all Bonferroni P < 0.05). Conclusions To provide insights into alternative classification and potential therapeutic targeting strategies of BRCA1-like hormone-receptor-positive tumors we developed and applied a novel copy number classifier to identify BRCA1-like hormone-receptor-positive tumors and their characteristic somatic alteration profiles. Electronic supplementary material The online version of this article (10.1186/s13058-018-1090-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Youdinghuan Chen
- Department of Epidemiology, Lebanon, USA.,Department of Molecular and Systems Biology, Lebanon, USA
| | - Yue Wang
- Department of Molecular and Systems Biology, Lebanon, USA
| | - Lucas A Salas
- Department of Epidemiology, Lebanon, USA.,Department of Molecular and Systems Biology, Lebanon, USA
| | - Todd W Miller
- Department of Molecular and Systems Biology, Lebanon, USA
| | - Kenneth Mark
- Department of Molecular and Systems Biology, Lebanon, USA
| | | | - Arminja N Kettenbach
- Department of Molecular and Systems Biology, Lebanon, USA.,Department of Biochemistry and Cell Biology, Lebanon, USA
| | - Chao Cheng
- Department of Molecular and Systems Biology, Lebanon, USA. .,Department of Biomedical Data Science, Lebanon, USA. .,Present address: Department of Medicine, Baylor College of Medicine, Room ICTR 100D, One Baylor Plaza, Houston, TX, 77030, USA.
| | - Brock C Christensen
- Department of Epidemiology, Lebanon, USA. .,Department of Molecular and Systems Biology, Lebanon, USA. .,Department of Community and Family Medicine, Dartmouth-Hitchcock Medical Center, 660 Williamson, HB 7650. One Medical Center Drive, Lebanon, NH, 03756, USA.
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40
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Kumar GS, Choy MS, Koveal DM, Lorinsky MK, Lyons SP, Kettenbach AN, Page R, Peti W. Identification of the substrate recruitment mechanism of the muscle glycogen protein phosphatase 1 holoenzyme. Sci Adv 2018; 4:eaau6044. [PMID: 30443599 PMCID: PMC6235537 DOI: 10.1126/sciadv.aau6044] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/15/2018] [Indexed: 05/04/2023]
Abstract
Glycogen is the primary storage form of glucose. Glycogen synthesis and breakdown are tightly controlled by glycogen synthase (GYS) and phosphorylase, respectively. The enzyme responsible for dephosphorylating GYS and phosphorylase, which results in their activation (GYS) or inactivation (phosphorylase) to robustly stimulate glycogen synthesis, is protein phosphatase 1 (PP1). However, our understanding of how PP1 recruits these substrates is limited. Here, we show how PP1, together with its muscle glycogen-targeting (GM) regulatory subunit, recruits and selectively dephosphorylates its substrates. Our molecular data reveal that the GM carbohydrate binding module (GM CBM21), which is amino-terminal to the GM PP1 binding domain, has a dual function in directing PP1 substrate specificity: It either directly recruits substrates (i.e., GYS) or recruits them indirectly by localization (via glycogen for phosphorylase). Our data provide the molecular basis for PP1 regulation by GM and reveal how PP1-mediated dephosphorylation is driven by scaffolding-based substrate recruitment.
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Affiliation(s)
- Ganesan Senthil Kumar
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Meng S. Choy
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Dorothy M. Koveal
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912, USA
| | - Michael K. Lorinsky
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Scott P. Lyons
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Rebecca Page
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Wolfgang Peti
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
- Corresponding author.
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Lyons SP, Jenkins NP, Nasa I, Choy MS, Adamo ME, Page R, Peti W, Moorhead GB, Kettenbach AN. A Quantitative Chemical Proteomic Strategy for Profiling Phosphoprotein Phosphatases from Yeast to Humans. Mol Cell Proteomics 2018; 17:2448-2461. [PMID: 30228194 DOI: 10.1074/mcp.ra118.000822] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 08/21/2018] [Indexed: 11/06/2022] Open
Abstract
A "tug-of-war" between kinases and phosphatases establishes the phosphorylation states of proteins. While serine and threonine phosphorylation can be catalyzed by more than 400 protein kinases, the majority of serine and threonine dephosphorylation is carried out by seven phosphoprotein phosphatases (PPPs). The PPP family consists of protein phosphatases 1 (PP1), 2A (PP2A), 2B (PP2B), 4 (PP4), 5 (PP5), 6 (PP6), and 7 (PP7). The imbalance in numbers between serine- and threonine-directed kinases and phosphatases led to the early belief that PPPs are unspecific and that kinases are the primary determinants of protein phosphorylation. However, it is now clear that PPPs achieve specificity through association with noncatalytic subunits to form multimeric holoenzymes, which expands the number of functionally distinct signaling entities to several hundred. Although there has been great progress in deciphering signaling by kinases, much less is known about phosphatases.We have developed a chemical proteomic strategy for the systematic interrogation of endogenous PPP catalytic subunits and their interacting proteins, including regulatory and scaffolding subunits (the "PPPome"). PP1, PP2A, PP4, PP5, and PP6 were captured using an immobilized, specific but nonselective PPP inhibitor microcystin-LR (MCLR), followed by protein identification by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in a single analysis. Here, we combine this approach of phosphatase inhibitor bead profiling and mass spectrometry (PIB-MS) with label-free and tandem mass tag (TMT) quantification to map the PPPome in human cancer cell lines, mouse tissues, and yeast species, through which we identify cell- and tissue-type-specific PPP expression patterns and discover new PPP interacting proteins.
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Affiliation(s)
- Scott P Lyons
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA
| | - Nicole P Jenkins
- Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH, USA
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH, USA
| | - Meng S Choy
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Mark E Adamo
- Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH, USA
| | - Rebecca Page
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Wolfgang Peti
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Greg B Moorhead
- Department of Biological Science, University of Calgary, Alberta, Canada
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center at Dartmouth, Lebanon, NH, USA.
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Zhao Y, Zurawel AA, Jenkins NP, Duennwald ML, Cheng C, Kettenbach AN, Supattapone S. Comparative Analysis of Mutant Huntingtin Binding Partners in Yeast Species. Sci Rep 2018; 8:9554. [PMID: 29934597 PMCID: PMC6015068 DOI: 10.1038/s41598-018-27900-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 06/12/2018] [Indexed: 12/21/2022] Open
Abstract
Huntington’s disease is caused by the pathological expansion of a polyglutamine (polyQ) stretch in Huntingtin (Htt), but the molecular mechanisms by which polyQ expansion in Htt causes toxicity in selective neuronal populations remain poorly understood. Interestingly, heterologous expression of expanded polyQ Htt is toxic in Saccharomyces cerevisiae cells, but has no effect in Schizosaccharomyces pombe, a related yeast species possessing very few endogenous polyQ or Q/N-rich proteins. Here, we used a comprehensive and unbiased mass spectrometric approach to identify proteins that bind Htt in a length-dependent manner in both species. Analysis of the expanded polyQ-associated proteins reveals marked enrichment of proteins that are localized to and play functional roles in nucleoli and mitochondria in S. cerevisiae, but not in S. pombe. Moreover, expanded polyQ Htt appears to interact preferentially with endogenous polyQ and Q/N-rich proteins, which are rare in S. pombe, as well as proteins containing coiled-coil motifs in S. cerevisiae. Taken together, these results suggest that polyQ expansion of Htt may cause cellular toxicity in S. cerevisiae by sequestering endogenous polyQ and Q/N-rich proteins, particularly within nucleoli and mitochondria.
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Affiliation(s)
- Yanding Zhao
- Departments of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States
| | - Ashley A Zurawel
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States
| | - Nicole P Jenkins
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States
| | - Martin L Duennwald
- Department of Pathology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, N6A 5C1, Canada
| | - Chao Cheng
- Departments of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States.,Biomedical Data Sciences, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States
| | - Arminja N Kettenbach
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States
| | - Surachai Supattapone
- Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States. .,Medicine, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, 03755, United States.
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Nasa I, Rusin SF, Kettenbach AN, Moorhead GB. Aurora B opposes PP1 function in mitosis by phosphorylating the conserved PP1-binding RVxF motif in PP1 regulatory proteins. Sci Signal 2018; 11:11/530/eaai8669. [PMID: 29764992 DOI: 10.1126/scisignal.aai8669] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Protein phosphatase 1 (PP1) is a highly conserved protein phosphatase that performs most of the serine- and threonine-dephosphorylation reactions in eukaryotes and opposes the actions of a diverse set of serine and threonine (Ser-Thr) protein kinases. PP1 gains substrate specificity through binding to a large number (>200) of regulatory proteins that control PP1 localization, activity, and interactions with substrates. PP1 recognizes the well-characterized RVxF binding motif that is present in many of these regulatory proteins, thus generating a multitude of distinct PP1 holoenzymes. We showed that a subset of the RVxF binding motifs, in which x is a phosphorylatable amino acid (RV[S/T]F), was phosphorylated specifically during mitosis and that this phosphorylation event abrogated the interaction of PP1 with the regulatory protein. We determined that this phosphorylation was primarily governed by the mitotic protein kinase Aurora B and that high phosphorylation site stoichiometry of these sites maintained the phosphorylation of PP1 substrates during mitosis by disrupting the assembly of PP1 holoenzymes. We generated an antibody that recognizes the phosphorylated form of the RV[S/T]F motif (RVp[S/T]F) and used it to identify known PP1 regulatory proteins (KNL1, CDCA2, and RIF1) and multiple proteins that could potentially act as PP1 binding partners (UBR5, ASPM, SEH1, and ELYS) governed by this mechanism. Together, these data suggest a general regulatory mechanism by which the coordinated activities of Aurora B and PP1 control mitotic progression.
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Affiliation(s)
- Isha Nasa
- Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Scott F Rusin
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA. .,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Greg B Moorhead
- Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
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Kettenbach AN, Schlosser KA, Lyons SP, Nasa I, Gui J, Adamo ME, Gerber SA. Global assessment of its network dynamics reveals that the kinase Plk1 inhibits the phosphatase PP6 to promote Aurora A activity. Sci Signal 2018; 11:eaaq1441. [PMID: 29764989 PMCID: PMC6002859 DOI: 10.1126/scisignal.aaq1441] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Polo-like kinase 1 (Plk1) is an essential protein kinase that promotes faithful mitotic progression in eukaryotes. The subcellular localization and substrate interactions of Plk1 are tightly controlled and require its binding to phosphorylated residues. To identify phosphorylation-dependent interactions within the Plk1 network in human mitotic cells, we performed quantitative proteomics on HeLa cells cultured with kinase inhibitors or expressing a Plk1 mutant that was deficient in phosphorylation-dependent substrate binding. We found that many interactions were abolished upon kinase inhibition; however, a subset was protected from phosphatase opposition or was unopposed, resulting in persistent interaction of the substrate with Plk1. This subset includes phosphoprotein phosphatase 6 (PP6), whose activity toward Aurora kinase A (Aurora A) was inhibited by Plk1. Our data suggest that this Plk1-PP6 interaction generates a feedback loop that coordinates and reinforces the activities of Plk1 and Aurora A during mitotic entry and is terminated by the degradation of Plk1 during mitotic exit. Thus, we have identified a mechanism for the previously puzzling observation of the Plk1-dependent regulation of Aurora A.
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Affiliation(s)
- Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Kate A Schlosser
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Scott P Lyons
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Jiang Gui
- Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Mark E Adamo
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Scott A Gerber
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
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45
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Nasa I, Kettenbach AN. Coordination of Protein Kinase and Phosphoprotein Phosphatase Activities in Mitosis. Front Cell Dev Biol 2018; 6:30. [PMID: 29623276 PMCID: PMC5874294 DOI: 10.3389/fcell.2018.00030] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 03/08/2018] [Indexed: 01/09/2023] Open
Abstract
Dynamic changes in protein phosphorylation govern the transitions between different phases of the cell division cycle. A "tug of war" between highly conserved protein kinases and the family of phosphoprotein phosphatases (PPP) establishes the phosphorylation state of proteins, which controls their function. More than three-quarters of all proteins are phosphorylated at one or more sites in human cells, with the highest occupancy of phosphorylation sites seen in mitosis. Spatial and temporal regulation of opposing kinase and PPP activities is crucial for accurate execution of the mitotic program. The role of mitotic kinases has been the focus of many studies, while the contribution of PPPs was for a long time underappreciated and is just emerging. Misconceptions regarding the specificity and activity of protein phosphatases led to the belief that protein kinases are the primary determinants of mitotic regulation, leaving PPPs out of the limelight. Recent studies have shown that protein phosphatases are specific and selective enzymes, and that their activity is tightly regulated. In this review, we discuss the emerging roles of PPPs in mitosis and their regulation of and by mitotic kinases, as well as mechanisms that determine PPP substrate recognition and specificity.
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Affiliation(s)
- Isha Nasa
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, United States
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, United States
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46
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Shee K, Hinds JW, Yang W, Hampsch RA, Patel K, Varn FS, Cheng C, Jenkins NP, Kettenbach AN, Demidenko E, Owens P, Lanari C, Faber AC, Golub TR, Straussman R, Miller TW. Abstract PD4-08: A microenvironment secretome screen reveals FGF2 as a mediator of resistance to anti-estrogens and PI3K/mTOR pathway inhibitors in ER+ breast cancer. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-pd4-08] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Despite the clinical success of anti-estrogen therapies, phosphatidylinositol 3-kinase inhibitors (PI3Ki), and mechanistic target of rapamycin complex I inhibitors (mTORC1i) for the treatment of patients with ER+ breast cancer, disease recurrence and progression are common. We found that a tumor transcriptional profile reflecting high stromal fibroblast content was associated with poor outcome in 3 cohorts of patients with ER+ breast cancer. We hypothesized that individual factors in the tumor microenvironment (TME) significantly contribute to drug resistance.
To test this hypothesis, we screened 297 recombinant secreted proteins for ability to confer resistance to the anti-estrogen fulvestrant in MCF-7 and T47D ER+ breast cancer cells. Screen results were validated, and expansion screening included the anti-estrogen tamoxifen, the PI3Ki pictilisib, and the mTORC1i everolimus in 4 cell lines. To identify hits are most likely to be relevant to ER+ breast cancer, a bioinformatics filter was developed utilizing gene and protein expression in human tissues relevant to the TMEs of ER+ breast cancer. After filtering, the top screening hit was fibroblast growth factor 2 (FGF2), which confers resistance to anti-estrogens, PI3Ki, and mTORC1i, and is highly expressed in tissues and cell types associated with ER+ breast cancer. FGF2 did not rescue cells from the CDK4/6i palbociclib or the DNA-damaging agent doxorubicin, demonstrating pathway selectivity in the rescue phenotype. FGF2 rescued cells from anti-estrogen-, PI3Ki-, and mTORC1i-induced apoptosis and cell cycle arrest via activation of FGFR signaling through FRS2a, MEK1/2, ERK1/2, and downstream upregulation of cyclin D1 and degradation of Bim. FGF2-mediated anti-cancer effects were abrogated by co-treatment with the FGF2-neutralizing antibody GAL-F2, the pan-FGFR inhibitor PD-173074, the MEK inhibitor trametinib, or palbociclib. Cell cycle- and apoptosis-specific effects of FGF2 were abrogated by RNAi targeting cyclin D1 and Bim, respectively.
We generated a transcriptional signature of FGF2 response by RNA-seq of fulvestrant-treated MCF-7 and T47D cells treated +/- FGF2. In 3 cohorts of patients with ER+ breast cancer, a signature of FGF2 signaling was significantly associated with poor prognosis and predictive of anti-estrogen resistance, including in a multivariate analysis including age, tumor grade, tumor stage, and FGFR amplification status. Finally, the therapeutic potential of targeting FGF2 was confirmed in 3 mouse models of ER+ breast cancer: 1) FGF2 rescue MCF-7 xenografts from fulvestrant; 2) GAL-F2 synergized with fulvestrant to suppress growth of 59-2-HI murine mammary adenocarcinomas that recruit FGF2-secreting stroma; 3) GAL-F2 synergized with fulvestrant to induce regression of HCI-003 patient-derived xenografts. Therapeutic effects coincided with increased tumor cell apoptosis and decreased proliferation, but not changes in tumor vasculature. These findings warrant consideration of FGF2 as a novel therapeutic target in ER+ breast cancer.
Citation Format: Shee K, Hinds JW, Yang W, Hampsch RA, Patel K, Varn FS, Cheng C, Jenkins NP, Kettenbach AN, Demidenko E, Owens P, Lanari C, Faber AC, Golub TR, Straussman R, Miller TW. A microenvironment secretome screen reveals FGF2 as a mediator of resistance to anti-estrogens and PI3K/mTOR pathway inhibitors in ER+ breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD4-08.
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Affiliation(s)
- K Shee
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - JW Hinds
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - W Yang
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - RA Hampsch
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - K Patel
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - FS Varn
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - C Cheng
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - NP Jenkins
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - AN Kettenbach
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - E Demidenko
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - P Owens
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - C Lanari
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - AC Faber
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - TR Golub
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - R Straussman
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
| | - TW Miller
- Geisel School of Medicine at Dartmouth, Lebanon, NH; Vanderbilt University School of Medicine, Nashville, TN; Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Virginia Commonwealth University, Richmond, VA; Broad Institute of MIT and Harvard, Cambridge, MA; Weizmann Institute of Science, Rehovot, Israel
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Shee K, Yang W, Hinds JW, Hampsch RA, Varn FS, Traphagen NA, Patel K, Cheng C, Jenkins NP, Kettenbach AN, Demidenko E, Owens P, Faber AC, Golub TR, Straussman R, Miller TW. Therapeutically targeting tumor microenvironment-mediated drug resistance in estrogen receptor-positive breast cancer. J Exp Med 2018; 215:895-910. [PMID: 29436393 PMCID: PMC5839765 DOI: 10.1084/jem.20171818] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 12/29/2017] [Accepted: 01/01/2018] [Indexed: 12/22/2022] Open
Abstract
Tumor microenvironment (TME) cytokine screening revealed FGF2 as a clinically relevant mechanism of resistance to anti-estrogens, mTORC1 inhibition, and PI3K inhibition in ER+ breast cancer. Shee et al. highlight an underdeveloped aspect of precision oncology: treating patients according to their TME constitution. Drug resistance to approved systemic therapies in estrogen receptor–positive (ER+) breast cancer remains common. We hypothesized that factors present in the human tumor microenvironment (TME) drive drug resistance. Screening of a library of recombinant secreted microenvironmental proteins revealed fibroblast growth factor 2 (FGF2) as a potent mediator of resistance to anti-estrogens, mTORC1 inhibition, and phosphatidylinositol 3-kinase inhibition in ER+ breast cancer. Phosphoproteomic analyses identified ERK1/2 as a major output of FGF2 signaling via FGF receptors (FGFRs), with consequent up-regulation of Cyclin D1 and down-regulation of Bim as mediators of drug resistance. FGF2-driven drug resistance in anti-estrogen–sensitive and –resistant models, including patient-derived xenografts, was reverted by neutralizing FGF2 or FGFRs. A transcriptomic signature of FGF2 signaling in primary tumors predicted shorter recurrence-free survival independently of age, grade, stage, and FGFR amplification status. These findings delineate FGF2 signaling as a ligand-based drug resistance mechanism and highlights an underdeveloped aspect of precision oncology: characterizing and treating patients according to their TME constitution.
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Affiliation(s)
- Kevin Shee
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Wei Yang
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - John W Hinds
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Riley A Hampsch
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Frederick S Varn
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH.,Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Nicole A Traphagen
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Kishan Patel
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Chao Cheng
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH.,Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Nicole P Jenkins
- Department of Biochemistry and Cell Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Eugene Demidenko
- Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Philip Owens
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN.,Research Medicine, Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN
| | - Anthony C Faber
- VCU Philips Institute for Oral Health Research, School of Dentistry and Massey Cancer Center, Virginia Commonwealth University, Richmond, VA
| | - Todd R Golub
- Broad Institute of MIT and Harvard, Cambridge, MA
| | - Ravid Straussman
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Todd W Miller
- Department of Molecular and Systems Biology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH .,Comprehensive Breast Program, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
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Lee ME, Rusin SF, Jenkins N, Kettenbach AN, Moseley JB. Mechanisms Connecting the Conserved Protein Kinases Ssp1, Kin1, and Pom1 in Fission Yeast Cell Polarity and Division. Curr Biol 2017; 28:84-92.e4. [PMID: 29249658 DOI: 10.1016/j.cub.2017.11.034] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/18/2017] [Accepted: 11/15/2017] [Indexed: 12/11/2022]
Abstract
Connections between the protein kinases that function within complex cell polarity networks are poorly understood. Rod-shaped fission yeast cells grow in a highly polarized manner, and genetic screens have identified many protein kinases, including the CaMKK-like Ssp1 and the MARK/PAR-1 family kinase Kin1, that are required for polarized growth and cell shape, but their functional mechanisms and connections have been unknown [1-5]. We found that Ssp1 promotes cell polarity by phosphorylating the activation loop of Kin1. Kin1 regulates cell polarity and cytokinesis through unknown mechanisms [4-7]. We performed a large-scale phosphoproteomic screen and found that Kin1 phosphorylates itself and Pal1 to promote growth at cell tips, and these proteins are interdependent for localization to growing cell tips. Additional Kin1 substrates for cell polarity and cytokinesis (Tea4, Mod5, Cdc15, and Cyk3) were also phosphorylated by a second kinase, the DYRK family member Pom1 [8]. Kin1 and Pom1 were enriched at opposite ends of growing cells, and they phosphorylated largely non-overlapping sites on shared substrates. Combined inhibition of both Kin1and Pom1 led to synthetic defects in their shared substrates Cdc15 and Cyk3, confirming a non-redundant functional connection through shared substrates. These findings uncover a new Ssp1-Kin1 signaling pathway, and define its functional and mechanistic connection with Pom1 signaling for cell polarity and cytokinesis. These kinases are conserved in many eukaryotes including humans, suggesting that similar connections and mechanisms might operate in a broad range of cells.
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Affiliation(s)
- Mid Eum Lee
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Scott F Rusin
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Nicole Jenkins
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA; Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA; Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - James B Moseley
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
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Choy MS, Swingle M, D’Arcy B, Abney K, Rusin SF, Kettenbach AN, Page R, Honkanen RE, Peti W. PP1:Tautomycetin Complex Reveals a Path toward the Development of PP1-Specific Inhibitors. J Am Chem Soc 2017; 139:17703-17706. [PMID: 29156132 PMCID: PMC5729109 DOI: 10.1021/jacs.7b09368] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Selective inhibitors for each serine/threonine phosphatase (PPP) are essential to investigate the biological actions of PPPs and to guide drug development. Biologically diverse organisms (e.g., cyanobacteria, dinoflagellates, beetles) produce structurally distinct toxins that are catalytic inhibitors of PPPs. However, most toxins exhibit little selectivity, typically inhibiting multiple family members with similar potencies. Thus, the use of these toxins as chemical tools to study the relationship between individual PPPs and their biological substrates, and how disruptions in these relationships contributes to human disease, is severely limited. Here, we show that tautomycetin (TTN) is highly selective for a single PPP, protein phosphatase 1 (PP1/PPP1C). Our structure of the PP1:TTN complex reveals that PP1 selectivity is defined by a covalent bond between TTN and a PP1-specific cysteine residue, Cys127. Together, these data provide key molecular insights needed for the development of novel probes targeting single PPPs, especially PP1.
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Affiliation(s)
- Meng S. Choy
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Mark Swingle
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama 36688, United States
| | - Brandon D’Arcy
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama 36688, United States
| | - Kevin Abney
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama 36688, United States
| | - Scott F. Rusin
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756, United States
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756, United States
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756, United States
| | - Rebecca Page
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Richard E. Honkanen
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama 36688, United States
| | - Wolfgang Peti
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
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Rusin SF, Adamo ME, Kettenbach AN. Identification of Candidate Casein Kinase 2 Substrates in Mitosis by Quantitative Phosphoproteomics. Front Cell Dev Biol 2017; 5:97. [PMID: 29214152 PMCID: PMC5702644 DOI: 10.3389/fcell.2017.00097] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/06/2017] [Indexed: 12/30/2022] Open
Abstract
Protein phosphorylation is a crucial regulatory mechanism that controls many aspects of cellular signaling. Casein kinase 2 (CK2), a constitutively expressed and active kinase, plays key roles in an array of cellular events including transcription and translation, ribosome biogenesis, cell cycle progression, and apoptosis. CK2 is implicated in cancerous transformation and is a therapeutic target in anti-cancer therapy. The specific and selective CK2 ATP competitive inhibitor, CX-4945 (silmitaseratib), is currently in phase 2 clinical trials. While many substrates and interactors of CK2 have been identified, less is known about CK2 substrates in mitosis. In the present work, we utilize CX-4945 and quantitative phosphoproteomics to inhibit CK2 activity in mitotically arrested HeLa cells and determine candidate CK2 substrates. We identify 330 phosphorylation sites on 202 proteins as significantly decreased in abundance upon inhibition of CK2 activity. Motif analysis of decreased sites reveals a linear kinase motif with aspartic and glutamic amino acids downstream of the phosphorylated residues, which is consistent with known substrate preferences for CK2. To validate specific candidate CK2 substrates, we perform in vitro kinase assays using purified components. Furthermore, we identified CK2 interacting proteins by affinity purification-mass spectrometry (AP-MS). To investigate the biological processes regulated by CK2 in mitosis, we perform network analysis and identify an enrichment of proteins involved in chromosome condensation, chromatin organization, and RNA processing. We demonstrate that overexpression of CK2 in HeLa cells affects proper chromosome condensation. Previously, we found that phosphoprotein phosphatase 6 (PP6), but not phosphoprotein phosphatase 2A (PP2A), opposes CK2 phosphorylation of the condensin I complex, which is essential for chromosome condensation. Here, we extend this observation and demonstrate that PP6 opposition of CK2 is a more general cellular regulatory mechanism.
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Affiliation(s)
- Scott F Rusin
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States
| | - Mark E Adamo
- Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, NH, United States
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States.,Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, NH, United States
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