1
|
Papi RM, Tasioulis KS, Kechagioglou PV, Papaioannou MA, Andriotis EG, Kyriakidis DA. Carbon Nanotube-Mediated Delivery of PTEN Variants: In Vitro Antitumor Activity in Breast Cancer Cells. Molecules 2024; 29:2785. [PMID: 38930850 PMCID: PMC11206347 DOI: 10.3390/molecules29122785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 05/27/2024] [Accepted: 06/08/2024] [Indexed: 06/28/2024] Open
Abstract
Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is a crucial tumor suppressor protein with frequent mutations and alterations. Although protein therapeutics are already integral to numerous medical fields, their potential remains nascent. This study aimed to investigate the impact of stable, unphosphorylated recombinant human full-length PTEN and its truncated variants, regarding their tumor suppression activity with multiwalled-carbon nanotubes (MW-CNTs) as vehicles for their delivery in breast cancer cells (T-47D, ZR-75-1, and MCF-7). The cloning, overexpression, and purification of PTEN variants were achieved from E. coli, followed by successful binding to CNTs. Cell incubation with protein-functionalized CNTs revealed that the full-length PTEN-CNTs significantly inhibited cancer cell growth and stimulated apoptosis in ZR-75-1 and MCF-7 cells, while truncated PTEN fragments on CNTs had a lesser effect. The N-terminal fragment, despite possessing the active site, did not have the same effect as the full length PTEN, emphasizing the necessity of interaction with the C2 domain in the C-terminal tail. Our findings highlight the efficacy of full-length PTEN in inhibiting cancer growth and inducing apoptosis through the alteration of the expression levels of key apoptotic markers. In addition, the utilization of carbon nanotubes as a potent PTEN protein delivery system provides valuable insights for future applications in in vivo models and clinical studies.
Collapse
Affiliation(s)
- Rigini M. Papi
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (K.S.T.); (P.V.K.); (D.A.K.)
| | - Konstantinos S. Tasioulis
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (K.S.T.); (P.V.K.); (D.A.K.)
| | - Petros V. Kechagioglou
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (K.S.T.); (P.V.K.); (D.A.K.)
| | - Maria A. Papaioannou
- Laboratory of Biological Chemistry, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece;
| | - Eleftherios G. Andriotis
- Laboratory of Organic Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece;
| | - Dimitrios A. Kyriakidis
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (K.S.T.); (P.V.K.); (D.A.K.)
| |
Collapse
|
2
|
Barbernitz MX, Devine LR, Cole RN, Raben DM. The role of N-terminal phosphorylation of DGK-θ. J Lipid Res 2024; 65:100506. [PMID: 38272356 PMCID: PMC10914586 DOI: 10.1016/j.jlr.2024.100506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/13/2024] [Accepted: 01/16/2024] [Indexed: 01/27/2024] Open
Abstract
Diacylglycerol kinases (DGKs) are lipid kinases that mediate the phosphorylation of diacylglycerol (DAG) leading to the production of phosphatidic acid (PtdOH). To examine the role of phosphorylation on DGK-θ, we first identified the phosphorylated sites on endogenous DGK-θ from mouse brain and found four sites: S15, S17, which we refer to phosphomotif-1 sites, and S22 and S26 which we refer to as phosphomotif-2 sites. This study focused on the role of these phosphorylated sites on enzyme activity, membrane binding, thermal stability, and cellular half-life of DGK-θ. After generating a construct devoid of all non-catalytic phosphorylation sites (4A), we also generated other constructs to mimic phosphorylation of these residues by mutating them to glutamate (E). Our data demonstrate that an increase in membrane affinity requires the phosphorylation of all four endogenous sites as the phosphomimetic 4E but not other phosphomimietics. Furthermore, 4E also shows an increase in basal activity as well as an increase in the Syt1-induced activity compared to 4A. It is noteworthy that these phosphorylations had no effect on the thermal stability or cellular half-life of this enzyme. Interestingly, when only one phosphorylation domain (phosphomotif-1 or phosphomotif-2) contained phosphomimetics (S15E/S17E or S22E/S26E), the basal activity was also increased but membrane binding affinity was not increased. Furthermore, when only one residue in each domain mimicked an endogenous phosphorylated serine (S15E/S22E or S17E/S26E), the Syt1-induced activity as well as membrane binding affinity decreased relative to 4A. These results indicate that these endogenous phosphorylation sites contribute differentially to membrane binding and enzymatic activity.
Collapse
Affiliation(s)
- Millie X Barbernitz
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Lauren R Devine
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert N Cole
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Daniel M Raben
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Physiology and Oncology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
3
|
De D, Ghosh G, Karmakar P. Sumoylation and phosphorylation of PTEN boosts and curtails autophagy respectively by influencing cell membrane localisation. Exp Cell Res 2024; 434:113872. [PMID: 38072303 DOI: 10.1016/j.yexcr.2023.113872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 11/30/2023] [Accepted: 12/03/2023] [Indexed: 12/17/2023]
Abstract
Autophagy is involved in the entirety of cellular survival, homeostasis and death which becomes more self-evident when its dysregulation is implicated in several pathological conditions. PTEN positively regulates autophagy and like other proteins undergo post-translational modifications. It is crucial to investigate the relationship between PTEN and autophagy as it is generally observed to be negligible in PTEN deficient cancer cells. Here, we have shown that such modifications of PTEN namely sumoylation and phosphorylation upregulates and downregulates autophagy respectively. Transfection of plasmid containing full length PTEN in PTEN-negative prostate cancer cell line PC3, induced autophagy on further starvation. When a sumoylation-deficient mutant of PTEN was transfected and cells were put under similar starvation, a decline in autophagy was observed. On the other hand, cells transfected with phosphorylation-deficient mutant of PTEN showed elevated expression of autophagy. Contrarily, transfection with phosphorylation-mimicking mutant caused reduced expression of autophagy. On further analysis, it was detected that PTEN's association with the plasma membrane was under positive and negative influence from its sumoylation and phosphorylation respectively. This association is integral as it is the foremost site for PTEN to oppose PI3K/AKT pathway and consequently upregulate autophagy. Thus, this study indicates that sumoylation and phosphorylation of PTEN can control autophagy via its cell membrane association.
Collapse
Affiliation(s)
- Debojyoti De
- Department of Life Science & Biotechnology, Jadavpur University, 188, Raja Subodh Chandra Mallick Road, Jadavpur, Kolkata, 700032, West Bengal, India.
| | - Ginia Ghosh
- Department of Life Science & Biotechnology, Jadavpur University, 188, Raja Subodh Chandra Mallick Road, Jadavpur, Kolkata, 700032, West Bengal, India.
| | - Parimal Karmakar
- Department of Life Science & Biotechnology, Jadavpur University, 188, Raja Subodh Chandra Mallick Road, Jadavpur, Kolkata, 700032, West Bengal, India.
| |
Collapse
|
4
|
Jang H, Chen J, Iakoucheva LM, Nussinov R. Cancer and Autism: How PTEN Mutations Degrade Function at the Membrane and Isoform Expression in the Human Brain. J Mol Biol 2023; 435:168354. [PMID: 37935253 PMCID: PMC10842829 DOI: 10.1016/j.jmb.2023.168354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/19/2023] [Accepted: 11/01/2023] [Indexed: 11/09/2023]
Abstract
Mutations causing loss of PTEN lipid phosphatase activity can promote cancer, benign tumors (PHTS), and neurodevelopmental disorders (NDDs). Exactly how they preferentially trigger distinct phenotypic outcomes has been puzzling. Here, we demonstrate that PTEN mutations differentially allosterically bias P loop dynamics and its connection to the catalytic site, affecting catalytic activity. NDD-related mutations are likely to sample conformations of the functional wild-type state, while sampled conformations for the strong, cancer-related driver mutation hotspots favor catalysis-primed conformations, suggesting that NDD mutations are likely to be weaker, and our large-scale simulations show why. Prenatal PTEN isoform expression data suggest exons 5 and 7, which harbor NDD mutations, as cancer-risk carriers. Since cancer requires more than a single mutation, our conformational and genomic analysis helps discover how same protein mutations can foster different clinical manifestations, articulates a role for co-occurring background latent driver mutations, and uncovers relationships of splicing isoform expression to life expectancy.
Collapse
Affiliation(s)
- Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Cancer Innovation Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Jiaye Chen
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA
| | - Lilia M Iakoucheva
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA; Institute for Genomic Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Cancer Innovation Laboratory, National Cancer Institute, Frederick, MD 21702, USA; Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
| |
Collapse
|
5
|
Yu J, Boehr DD. Regulatory mechanisms triggered by enzyme interactions with lipid membrane surfaces. Front Mol Biosci 2023; 10:1306483. [PMID: 38099197 PMCID: PMC10720463 DOI: 10.3389/fmolb.2023.1306483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 11/17/2023] [Indexed: 12/17/2023] Open
Abstract
Recruitment of enzymes to intracellular membranes often modulates their catalytic activity, which can be important in cell signaling and membrane trafficking. Thus, re-localization is not only important for these enzymes to gain access to their substrates, but membrane interactions often allosterically regulate enzyme function by inducing conformational changes across different time and amplitude scales. Recent structural, biophysical and computational studies have revealed how key enzymes interact with lipid membrane surfaces, and how this membrane binding regulates protein structure and function. This review summarizes the recent progress in understanding regulatory mechanisms involved in enzyme-membrane interactions.
Collapse
Affiliation(s)
| | - David D. Boehr
- Department of Chemistry, The Pennsylvania State University, University Park, PA, United States
| |
Collapse
|
6
|
Nikolsky KS, Kulikova LI, Petrovskiy DV, Rudnev VR, Malsagova KA, Kaysheva AL. Analysis of Structural Changes in the Protein near the Phosphorylation Site. Biomolecules 2023; 13:1564. [PMID: 38002246 PMCID: PMC10668964 DOI: 10.3390/biom13111564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/13/2023] [Accepted: 10/14/2023] [Indexed: 11/26/2023] Open
Abstract
Modification of the protein after synthesis (PTM) often affects protein function as supported by numerous studies. However, there is no consensus about the degree of structural protein changes after modification. For phosphorylation of serine, threonine, and tyrosine, which is a common PTM in the biology of living organisms, we consider topical issues related to changes in the geometric parameters of a protein (Rg, RMSD, Cα displacement, SASA). The effect of phosphorylation on protein geometry was studied both for the whole protein and at the local level (i.e., in different neighborhoods of the modification site). Heterogeneity in the degree of protein structural changes after phosphorylation was revealed, which allowed for us to isolate a group of proteins having pronounced local structural changes in the neighborhoods of up to 15 amino acid residues from the modification site. This is a comparative study of protein structural changes in neighborhoods of 3-15 amino acid residues from the modified site. Amino acid phosphorylation in proteins with pronounced local changes caused switching from the inactive functional state to the active one.
Collapse
Affiliation(s)
| | | | | | | | - Kristina A. Malsagova
- Institute of Biomedical Chemistry, Biobanking Group, Pogodinskaya, 10, 119121 Moscow, Russia; (K.S.N.); (L.I.K.); (D.V.P.); (V.R.R.); (A.L.K.)
| | | |
Collapse
|
7
|
Leonard TA, Loose M, Martens S. The membrane surface as a platform that organizes cellular and biochemical processes. Dev Cell 2023; 58:1315-1332. [PMID: 37419118 DOI: 10.1016/j.devcel.2023.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/22/2023] [Accepted: 06/08/2023] [Indexed: 07/09/2023]
Abstract
Membranes are essential for life. They act as semi-permeable boundaries that define cells and organelles. In addition, their surfaces actively participate in biochemical reaction networks, where they confine proteins, align reaction partners, and directly control enzymatic activities. Membrane-localized reactions shape cellular membranes, define the identity of organelles, compartmentalize biochemical processes, and can even be the source of signaling gradients that originate at the plasma membrane and reach into the cytoplasm and nucleus. The membrane surface is, therefore, an essential platform upon which myriad cellular processes are scaffolded. In this review, we summarize our current understanding of the biophysics and biochemistry of membrane-localized reactions with particular focus on insights derived from reconstituted and cellular systems. We discuss how the interplay of cellular factors results in their self-organization, condensation, assembly, and activity, and the emergent properties derived from them.
Collapse
Affiliation(s)
- Thomas A Leonard
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Dr. Bohr-Gasse 9, 1030, Vienna, Austria; Medical University of Vienna, Center for Medical Biochemistry, Dr. Bohr-Gasse 9, 1030, Vienna, Austria.
| | - Martin Loose
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria.
| | - Sascha Martens
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Dr. Bohr-Gasse 9, 1030, Vienna, Austria; University of Vienna, Center for Molecular Biology, Department of Biochemistry and Cell Biology, Dr. Bohr-Gasse 9, 1030, Vienna, Austria.
| |
Collapse
|
8
|
Iwase R, Dempsey DR, Whedon SD, Jiang H, Palanski BA, Deng B, Cole PA. Semisynthetic Approach to the Analysis of Tumor Suppressor PTEN Ubiquitination. J Am Chem Soc 2023; 145:6039-6044. [PMID: 36897111 PMCID: PMC10071500 DOI: 10.1021/jacs.2c13871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Phosphatase and tensin homologue (PTEN) tumor suppressor protein is a PIP3 lipid phosphatase that is subject to multifaceted post-translational modifications. One such modification is the monoubiquitination of Lys13 that may alter its cellular localization but is also positioned in a manner that could influence several of its cellular functions. To explore the regulatory influence of ubiquitin on PTEN's biochemical properties and its interaction with ubiquitin ligases and a deubiquitinase, the generation of a site-specifically and stoichiometrically ubiquitinated protein could be beneficial. Here, we describe a semisynthetic method that relies upon sequential expressed protein ligation steps to install ubiquitin at a Lys13 mimic in near full-length PTEN. This approach permits the concurrent installation of C-terminal modifications in PTEN, thereby facilitating an analysis of the interplay between N-terminal ubiquitination and C-terminal phosphorylation. We find that the N-terminal ubiquitination of PTEN inhibits its enzymatic function, reduces its binding to lipid vesicles, modulates its processing by NEDD4-1 E3 ligase, and is efficiently cleaved by the deubiquitinase, USP7. Our ligation approach should motivate related efforts for uncovering the effects of ubiquitination of complex proteins.
Collapse
Affiliation(s)
- Reina Iwase
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Daniel R. Dempsey
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, United States
- Department of Dermatology and Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts 02118, United States
| | - Samuel D. Whedon
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Hanjie Jiang
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Brad A. Palanski
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Bedphiny Deng
- Dana-Farber/Harvard Cancer Center, Boston, Massachusetts 02115, United States
- College of Natural Sciences, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Philip A. Cole
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, United States
| |
Collapse
|
9
|
Jang H, Chen J, Iakoucheva LM, Nussinov R. How PTEN mutations degrade function at the membrane and life expectancy of carriers of mutations in the human brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.26.525746. [PMID: 36747841 PMCID: PMC9900933 DOI: 10.1101/2023.01.26.525746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PTEN dysfunction, caused by loss of lipid phosphatase activity or deletion, promotes pathologies, cancer, benign tumors, and neurodevelopmental disorders (NDDs). Despite efforts, exactly how the mutations trigger distinct phenotypic outcomes, cancer or NDD, has been puzzling. It has also been unclear how to distinguish between mutations harbored by isoforms, are they cancer or NDDs-related. Here we address both. We demonstrate that PTEN mutations differentially allosterically bias P-loop dynamics and its connection to the catalytic site, affecting catalytic activity. NDD-related mutations are likely to sample conformations present in the wild-type, while sampled conformations sheltering cancer-related hotspots favor catalysis-prone conformations, suggesting that NDD mutations are weaker. Analysis of isoform expression data indicates that if the transcript has NDD-related mutations, alone or in combination with cancer hotspots, there is high prenatal expression. If no mutations within the measured days, low expression levels. Cancer mutations promote stronger signaling and cell proliferation; NDDs' are weaker, influencing brain cell differentiation. Further, exon 5 is impacted by NDD or non-NDD mutations, while exon 7 is exclusively impacted by NDD mutations. Our comprehensive conformational and genomic analysis helps discover how same allele mutations can foster different clinical manifestations and uncovers correlations of splicing isoform expression to life expectancy.
Collapse
Affiliation(s)
- Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Cancer Innovation Laboratory, National Cancer Institute, Frederick, MD 21702, U.S.A
| | - Jiaye Chen
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, U.S.A
| | - Lilia M Iakoucheva
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, U.S.A
- Institute for Genomic Medicine, University of California San Diego, La Jolla, CA 92093, U.S.A
| | - Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Cancer Innovation Laboratory, National Cancer Institute, Frederick, MD 21702, U.S.A
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| |
Collapse
|
10
|
Smith IN, Dawson JE, Eng C. Comparative Protein Structural Network Analysis Reveals C-Terminal Tail Phosphorylation Structural Communication Fingerprint in PTEN-Associated Mutations in Autism and Cancer. J Phys Chem B 2023; 127:634-647. [PMID: 36626331 PMCID: PMC9885960 DOI: 10.1021/acs.jpcb.2c06776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/24/2022] [Indexed: 01/11/2023]
Abstract
PTEN (phosphatase and tensin homolog deleted on chromosome 10) is a tightly regulated dual-specificity phosphatase and key regulator of the PI3K/AKT/mTOR signaling pathway. PTEN phosphorylation at its carboxy-terminal tail (CTT) serine/threonine cluster negatively regulates its tumor suppressor function by inducing a stable, closed, and inactive conformation. Germline PTEN mutations predispose individuals to PTEN hamartoma tumor syndrome (PHTS), a rare inherited cancer syndrome and, intriguingly, one of the most common causes of autism spectrum disorder (ASD). However, the mechanistic details that govern phosphorylated CTT catalytic conformational dynamics in the context of PHTS-associated mutations are unknown. Here, we utilized a comparative protein structure network (PSN)-based approach to investigate PTEN CTT phosphorylation-induced conformational dynamics specific to PTEN-ASD compared to PTEN-cancer phenotypes. Results from our study show differences in structural flexibility, inter-residue contacts, and allosteric communication patterns mediated by CTT phosphorylation, differentiating PTEN-ASD and PTEN-cancer phenotypes. Further, we identified perturbations among global metapaths and community network connections within the active site and inter-domain regions, indicating the significance of these regions in transmitting information across the PSN. Together, our studies provide a mechanistic underpinning of allosteric regulation through the coupled interplay of CTT phosphorylation conformational dynamics in PTEN-ASD and PTEN-cancer mutations. Importantly, the detailed atomistic interactions and structural consequences of PTEN variants reveal potential allosteric druggable target sites as a viable and currently unexplored treatment approach for individuals with different PHTS-associated mutations.
Collapse
Affiliation(s)
- Iris N. Smith
- Genomic
Medicine Institute, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, NE-50, Cleveland, Ohio44195, United States
| | - Jennifer E. Dawson
- Genomic
Medicine Institute, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, NE-50, Cleveland, Ohio44195, United States
| | - Charis Eng
- Genomic
Medicine Institute, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, NE-50, Cleveland, Ohio44195, United States
- Cleveland
Clinic Lerner College of Medicine, Case
Western Reserve University, 9500 Euclid Avenue, Cleveland, Ohio44195, United
States
- Case
Comprehensive Cancer Center, Case Western
Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio44106, United States
- Taussig
Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, Ohio44195, United States
- Department
of Genetics and Genome Sciences, Case Western
Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio44106, United States
| |
Collapse
|
11
|
Adelakun N, Parrish J, Chu N. Analyzing protein posttranslational modifications using enzyme-catalyzed expressed protein ligation. Methods Enzymol 2023; 682:319-350. [PMID: 36948706 DOI: 10.1016/bs.mie.2022.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Expressed protein ligation (EPL) allows for the attachment of a synthetic peptide into the N- or C-terminus of a recombinant protein fragment to generate a site-specifically modified protein with substantial yields for biochemical and biophysical studies. In this method, multiple posttranslational modifications (PTMs) can be incorporated into a synthetic peptide containing an N-terminal Cysteine, which selectively reacts with a protein C-terminal thioester to afford an amide bond formation. However, the requirement of a Cysteine at the ligation site can limit EPL's potential applications. Here, we describe a method called enzyme-catalyzed EPL, which uses subtiligase to ligate protein thioesters with Cysteine-free peptides. The procedure includes generating protein C-terminal thioester and peptide, performing the enzymatic EPL reaction, and purifying the protein ligation product. We exemplify this method by generating phospholipid phosphatase PTEN with site-specific phosphorylations installed onto its C-terminal tail for biochemical assays.
Collapse
Affiliation(s)
- Niyi Adelakun
- Department of Cancer Biology and Genetics, the Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Jordan Parrish
- Department of Cancer Biology and Genetics, the Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Nam Chu
- Department of Cancer Biology and Genetics, the Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, OH, United States.
| |
Collapse
|
12
|
Viennet T, Rodriguez Ospina S, Lu Y, Cui A, Arthanari H, Dempsey DR. Chemical and structural approaches to investigate PTEN function and regulation. Methods Enzymol 2022; 682:289-318. [PMID: 36948705 PMCID: PMC10037535 DOI: 10.1016/bs.mie.2022.09.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Phosphatase and tensin homolog is a lipid phosphatase that serves as the major negative regulator of the PI3K/AKT pathway. It catalyzes the 3'-specific dephosphorylation of phosphatidylinositol (3,4,5)-trisphosphate (PIP3) to generate PIP2. PTEN's lipid phosphatase function depends on several domains, including an N-terminal segment spanning the first 24 amino acids, which results in a catalytically impaired enzyme when mutated. Furthermore, PTEN is regulated by a cluster of phosphorylation sites located on its C-terminal tail at Ser380, Thr382, Thr383, and Ser385, which drives its conformation from an open to a closed autoinhibited but stable state. Herein, we discuss the protein chemical strategies we used to reveal the structure and mechanism of how PTEN's terminal regions govern its function.
Collapse
Affiliation(s)
- Thibault Viennet
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, United States; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Santiago Rodriguez Ospina
- Department of Dermatology, Boston University School of Medicine, Boston, MA, United States; Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Yunqi Lu
- Department of Dermatology, Boston University School of Medicine, Boston, MA, United States; Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Anna Cui
- Department of Dermatology, Boston University School of Medicine, Boston, MA, United States; Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Haribabu Arthanari
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, United States; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Daniel R Dempsey
- Department of Dermatology, Boston University School of Medicine, Boston, MA, United States; Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States.
| |
Collapse
|
13
|
Barbernitz X, Raben DM. Phosphorylation of DGK. Adv Biol Regul 2022; 88:100941. [PMID: 36508895 DOI: 10.1016/j.jbior.2022.100941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022]
Abstract
Diacylglycerol (DAG) and phosphatidic acid (PtdOH) play important roles in a variety of signaling cascades (Carrasco and Merida, 2007; Stace and Ktistakis, 2006). Therefore, the physiological roles and regulatory mechanisms controlling the levels of these lipids are important. One class of enzymes capable of coordinating the levels of these two lipids are the diacylglycerol kinases (DGKs). DGKs catalyze the transfer of the γ-phosphate of ATP to the hydroxyl group of DAG which generates PtdOH(Merida et al., 2008; Sakane et al., 2007). As DGKs reciprocally modulate the relative levels of these two signaling lipids, it is not surprising that there is increasing interest in understanding the mechanism underlying the catalysis and regulation of these kinases. While post-translational modifications (PTMs) are often involved in enzyme regulation, there is surprisingly little information regarding the PTMs on these enzymes and their roles in modulating their activity and function. In this review, we will summarize what is known about one PTM on DGKs, phosphorylation, and the possible functions of this modification.
Collapse
Affiliation(s)
- Xin Barbernitz
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Daniel M Raben
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
14
|
He F, Zhang F, Liao Y, Tang MS, Wu XR. Structural or functional defects of PTEN in urothelial cells lacking P53 drive basal/squamous-subtype muscle-invasive bladder cancer. Cancer Lett 2022; 550:215924. [PMID: 36195293 PMCID: PMC9813857 DOI: 10.1016/j.canlet.2022.215924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/10/2022] [Accepted: 09/19/2022] [Indexed: 01/07/2023]
Abstract
Muscle-invasive bladder cancer (MIBC) exhibits strong inter- and intra-tumor heterogeneity that affects biological behaviors, therapeutic responses, and prognoses. Mutations that activate RTK-RAS-PI3K and inactivate P19-P53-P21 coexist in 60-70% of MIBC. By time-controlled ablation of Tp53 and Pten, singly or combined, in adult mouse urothelium, we found that Tp53 loss alone produced no abnormality. While Pten loss elicited hyperplasia, it synergized with Tp53 loss to trigger 100% penetrant MIBC that exhibited basal/squamous features that resembled its human counterpart. Furthermore, PTEN was inactivated in human MIBC cell lines and specimens primarily by hyperphosphorylation of the C-terminus. Mutated or tailless PTEN incapable of C-terminal phosphorylation demonstrated increased inhibition of proliferation and invasion than full-length PTEN in cultured MIBC cells. In xenograft and transgenic mice, tailless PTEN, but not full-length PTEN, prevented further growth in established tumors. Collectively, deficiencies of both PTEN and P53 drive basal/squamous subtype MIBC. PTEN is inactivated by C-terminal hyperphosphorylation, and this modification may serve as a biomarker for subtyping MIBC and predicting tumor progression. Tailless PTEN is a potential molecular therapeutic for tumors, such as bladder cancer (BC), that can be readily accessed.
Collapse
Affiliation(s)
- Feng He
- Department of Urology, New York University School of Medicine, New York, NY, 10016, USA; Veterans Affairs New York Harbor Healthcare System, Manhattan Campus, New York, NY, 10010, USA
| | - Fenglin Zhang
- Department of Urology, New York University School of Medicine, New York, NY, 10016, USA
| | - Yi Liao
- Department of Urology, New York University School of Medicine, New York, NY, 10016, USA
| | - Moon-Shong Tang
- Department of Environmental Medicine, New York University School of Medicine, New York, NY, 10010, USA
| | - Xue-Ru Wu
- Department of Urology, New York University School of Medicine, New York, NY, 10016, USA; Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA; Veterans Affairs New York Harbor Healthcare System, Manhattan Campus, New York, NY, 10010, USA.
| |
Collapse
|
15
|
Kotzampasi DM, Premeti K, Papafotika A, Syropoulou V, Christoforidis S, Cournia Z, Leondaritis G. The orchestrated signaling by PI3Kα and PTEN at the membrane interface. Comput Struct Biotechnol J 2022; 20:5607-5621. [PMID: 36284707 PMCID: PMC9578963 DOI: 10.1016/j.csbj.2022.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/03/2022] [Accepted: 10/03/2022] [Indexed: 11/16/2022] Open
Abstract
The oncogene PI3Kα and the tumor suppressor PTEN represent two antagonistic enzymatic activities that regulate the interconversion of the phosphoinositide lipids PI(4,5)P2 and PI(3,4,5)P3 in membranes. As such, they are defining components of phosphoinositide-based cellular signaling and membrane trafficking pathways that regulate cell survival, growth, and proliferation, and are often deregulated in cancer. In this review, we highlight aspects of PI3Kα and PTEN interplay at the intersection of signaling and membrane trafficking. We also discuss the mechanisms of PI3Kα- and PTEN- membrane interaction and catalytic activation, which are fundamental for our understanding of the structural and allosteric implications on signaling at the membrane interface and may aid current efforts in pharmacological targeting of these proteins.
Collapse
Affiliation(s)
- Danai Maria Kotzampasi
- Biomedical Research Foundation, Academy of Athens, Athens 11527, Greece
- Department of Biology, University of Crete, Heraklion 71500, Greece
| | - Kyriaki Premeti
- Laboratory of Pharmacology, Faculty of Medicine, University of Ioannina, Ioannina 45110, Greece
| | - Alexandra Papafotika
- Laboratory of Biological Chemistry, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina 45110, Greece
- Biomedical Research Institute, Foundation for Research and Technology, Ioannina 45110, Greece
| | - Vasiliki Syropoulou
- Laboratory of Pharmacology, Faculty of Medicine, University of Ioannina, Ioannina 45110, Greece
| | - Savvas Christoforidis
- Laboratory of Biological Chemistry, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina 45110, Greece
- Biomedical Research Institute, Foundation for Research and Technology, Ioannina 45110, Greece
| | - Zoe Cournia
- Biomedical Research Foundation, Academy of Athens, Athens 11527, Greece
| | - George Leondaritis
- Laboratory of Pharmacology, Faculty of Medicine, University of Ioannina, Ioannina 45110, Greece
- Institute of Biosciences, University Research Center of Ioannina, Ioannina 45110, Greece
| |
Collapse
|
16
|
Smith IN, Dawson JE, Krieger J, Thacker S, Bahar I, Eng C. Structural and Dynamic Effects of PTEN C-Terminal Tail Phosphorylation. J Chem Inf Model 2022; 62:4175-4190. [PMID: 36001481 PMCID: PMC9472802 DOI: 10.1021/acs.jcim.2c00441] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Indexed: 11/28/2022]
Abstract
The phosphatase and tensin homologue deleted on chromosome 10 (PTEN) tumor suppressor gene encodes a tightly regulated dual-specificity phosphatase that serves as the master regulator of PI3K/AKT/mTOR signaling. The carboxy-terminal tail (CTT) is key to regulation and harbors multiple phosphorylation sites (Ser/Thr residues 380-385). CTT phosphorylation suppresses the phosphatase activity by inducing a stable, closed conformation. However, little is known about the mechanisms of phosphorylation-induced CTT-deactivation dynamics. Using explicit solvent microsecond molecular dynamics simulations, we show that CTT phosphorylation leads to a partially collapsed conformation, which alters the secondary structure of PTEN and induces long-range conformational rearrangements that encompass the active site. The active site rearrangements prevent localization of PTEN to the membrane, precluding lipid phosphatase activity. Notably, we have identified phosphorylation-induced allosteric coupling between the interdomain region and a hydrophobic site neighboring the active site in the phosphatase domain. Collectively, the results provide a mechanistic understanding of CTT phosphorylation dynamics and reveal potential druggable allosteric sites in a previously believed clinically undruggable protein.
Collapse
Affiliation(s)
- Iris N. Smith
- Genomic
Medicine Institute, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, NE-50, Cleveland, Ohio 44195, United States
| | - Jennifer E. Dawson
- Genomic
Medicine Institute, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, NE-50, Cleveland, Ohio 44195, United States
| | - James Krieger
- Department
of Computational and Systems Biology, University
of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, Pennsylvania 15260, United States
| | - Stetson Thacker
- Genomic
Medicine Institute, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, NE-50, Cleveland, Ohio 44195, United States
- Cleveland
Clinic Lerner College of Medicine, Case
Western Reserve University, 9500 Euclid Avenue, Cleveland, Ohio 44195, United
States
| | - Ivet Bahar
- Department
of Computational and Systems Biology, University
of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, Pennsylvania 15260, United States
| | - Charis Eng
- Genomic
Medicine Institute, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, NE-50, Cleveland, Ohio 44195, United States
- Cleveland
Clinic Lerner College of Medicine, Case
Western Reserve University, 9500 Euclid Avenue, Cleveland, Ohio 44195, United
States
- Case
Comprehensive Cancer Center, Case Western
Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
- Taussig
Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, Ohio 44195, United States
- Department
of Genetics and Genome Sciences, Case Western
Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| |
Collapse
|
17
|
Bae H, Viennet T, Park E, Chu N, Salguero A, Eck MJ, Arthanari H, Cole PA. PH domain-mediated autoinhibition and oncogenic activation of Akt. eLife 2022; 11:80148. [PMID: 35968932 PMCID: PMC9417420 DOI: 10.7554/elife.80148] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 08/09/2022] [Indexed: 11/13/2022] Open
Abstract
Akt is a Ser/Thr protein kinase that plays a central role in metabolism and cancer. Regulation of Akt’s activity involves an autoinhibitory intramolecular interaction between its pleckstrin homology (PH) domain and its kinase domain that can be relieved by C-tail phosphorylation. PH domain mutant E17K Akt is a well-established oncogene. Previously, we reported that the conformation of autoinhibited Akt may be shifted by small molecule allosteric inhibitors limiting the mechanistic insights from existing X-ray structures that have relied on such compounds (Chu et al., 2020). Here, we discover unexpectedly that a single mutation R86A Akt exhibits intensified autoinhibitory features with enhanced PH domain-kinase domain affinity. Structural and biochemical analysis uncovers the importance of a key interaction network involving Arg86, Glu17, and Tyr18 that controls Akt conformation and activity. Our studies also shed light on the molecular basis for E17K Akt activation as an oncogenic driver.
Collapse
Affiliation(s)
- Hwan Bae
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, United States
| | - Thibault Viennet
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, United States
| | - Eunyoung Park
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, United States
| | - Nam Chu
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, United States
| | - Antonieta Salguero
- Department of Medicine, Brigham and Women's Hospital, Boston, United States
| | - Michael J Eck
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, United States
| | - Haribabu Arthanari
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, United States
| | - Philip A Cole
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, United States
| |
Collapse
|
18
|
Zhang R, Ai J, Wang J, Sun C, Lu H, He A, Li M, Liao Y, Lei J, Zhou F, Wu L, Liao W. NCAPG promotes the proliferation of hepatocellular carcinoma through the CKII-dependent regulation of PTEN. J Transl Med 2022; 20:325. [PMID: 35864529 PMCID: PMC9301831 DOI: 10.1186/s12967-022-03519-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 07/07/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND NCAPG, non-SMC subunit in the concentrate I complex, might promote the proliferation of hepatocellular carcinoma (HCC), but the mechanism is unclear. The aim of this study was to explore how NCAPG affects PTEN to influence the proliferation of HCC. METHODS Western blotting, qRT-PCR and immunohistochemistry were used to detect NCAPG expression in HCC tissues. The effect of NCAPG on the proliferation of HCC cell lines was evaluated using an EdU incorporation assay, a Cell Counting Kit-8 assay and Fluorescence in situ hybridization (FISH). BALB/c-nu/nu mice were used for the in vivo proliferation experiment. Transcriptome sequencing was used to determine the relationship between NCAPG and PTEN. Immunocoprecipitation-mass spectrometry (IP-MS), proteomic sequencing and Co-immunoprecipitation (CO-IP) were used to identify and examine the interaction between the NCAPG and CKII proteins. RESULTS We confirmed that NCAPG was abnormally overexpressed in HCC and promoted the proliferation of HCC cells. Transcriptome sequencing revealed that NCAPG inhibited the transcription of PTEN and promoted the activation of the PI3K-AKT pathway. We found a close association between NCAPG and CKII through proteomic sequencing; their interaction was confirmed by Co-IP. There was a positive correlation between NCAPG and CKII that promoted the phosphorylation of PTEN and thus inhibited its transcription and functions. We also proved that CKII was the key factor in the induction of proliferation by NCAPG. CONCLUSION We revealed the mechanism by which NCAPG regulates the proliferation of HCC: NCAPG inhibits PTEN through its interaction with CKII, and then activates the PI3K-AKT pathway to promote the proliferation of HCC.
Collapse
Affiliation(s)
- Rongguiyi Zhang
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Jiyuan Ai
- Department of General Surgery, The Third Hospital of Nanchang City, No. 2, Xiangshan South Road, Nanchang, 330006, China
| | - Jiakun Wang
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Chi Sun
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Hongcheng Lu
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Aoxiao He
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Min Li
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Yuting Liao
- Department of Nursing, Gannan Medical College, No. 1, Medical Road, Ganzhou, 341000, China
| | - Jun Lei
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Fan Zhou
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China
| | - Linquan Wu
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China.
| | - Wenjun Liao
- Department of General Surgery, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Nanchang, 330006, China.
| |
Collapse
|
19
|
Salguero AL, Chen M, Balana AT, Chu N, Jiang H, Palanski BA, Bae H, Wright KM, Nathan S, Zhu H, Gabelli SB, Pratt MR, Cole PA. Multifaceted Regulation of Akt by Diverse C-Terminal Post-translational Modifications. ACS Chem Biol 2022; 17:68-76. [PMID: 34941261 DOI: 10.1021/acschembio.1c00632] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Akt is a Ser/Thr protein kinase that regulates cell growth and metabolism and is considered a therapeutic target for cancer. Regulation of Akt by membrane recruitment and post-translational modifications (PTMs) has been extensively studied. The most well-established mechanism for cellular Akt activation involves phosphorylation on its activation loop on Thr308 by PDK1 and on its C-terminal tail on Ser473 by mTORC2. In addition, dual phosphorylation on Ser477 and Thr479 has been shown to activate Akt. Other C-terminal tail PTMs have been identified, but their functional impacts have not been well-characterized. Here, we investigate the regulatory effects of phosphorylation of Tyr474 and O-GlcNAcylation of Ser473 on Akt. We use expressed protein ligation as a tool to produce semisynthetic Akt proteins containing phosphoTyr474 and O-GlcNAcSer473 to dissect the enzymatic functions of these PTMs. We find that O-GlcNAcylation at Ser473 and phosphorylation at Tyr474 can also partially increase Akt's kinase activity toward both peptide and protein substrates. Additionally, we performed kinase assays employing human protein microarrays to investigate global substrate specificity of Akt, comparing phosphorylated versus O-GlcNAcylated Ser473 forms. We observed a high similarity in the protein substrates phosphorylated by phosphoSer473 Akt and O-GlcNAcSer473 Akt. Two Akt substrates identified using microarrays, PPM1H, a protein phosphatase, and NEDD4L, an E3 ubiquitin ligase, were validated in solution-phase assays and cell transfection experiments.
Collapse
Affiliation(s)
- Antonieta L. Salguero
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Maggie Chen
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Aaron T. Balana
- Department of Chemistry, University of Southern California, Los Angeles, California 90089 United States
| | - Nam Chu
- Department of Cancer Biology and Genetics, and the Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, United States
| | - Hanjie Jiang
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Brad A. Palanski
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Hwan Bae
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Katharine M. Wright
- Department of Biophysics and Biophysical Chemistry, The Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Sara Nathan
- Department of Biophysics and Biophysical Chemistry, The Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Heng Zhu
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
- The Center for High-Throughput Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Sandra B. Gabelli
- Department of Biophysics and Biophysical Chemistry, The Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
- Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, United States
| | - Matthew R. Pratt
- Departments of Chemistry and Biological Sciences, University of Southern California, Los Angeles, California 90089 United States
| | - Philip A. Cole
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| |
Collapse
|
20
|
Butts M, Nam Chu. Utilizing a Baculovirus/Insect Cell Expression System and Expressed Protein Ligation (EPL) for Protein Semisynthesis. Curr Protoc 2022; 2:e348. [PMID: 35044726 PMCID: PMC8855479 DOI: 10.1002/cpz1.348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Protein semisynthesis has been used for the chemoselective linking of synthetic peptides and recombinant protein fragments to generate complete native proteins in good yield. The ability to site-selectively incorporate multiple post-translational chemical modifications (PTMs) into proteins via this approach shows great potential for enhancing understanding of the molecular basis of protein function and regulation. Protein semisynthesis, however, often requires high expression efficiency of the recombinant protein fragments (i.e., high expression yield and ability to preserve protein biological functions), which can be hard to achieve for some human enzymes when using bacterial expression systems. Here, we describe how to use a baculovirus/insect cell expression system and a protein semisynthesis strategy known as expressed protein ligation (EPL) to produce workable levels of proteins of interest containing site-specific chemical modifications. The protocol provides detailed guidance for generating protein C-terminal thioesters for use with the EPL reaction, performing the EPL reaction, and purifying the protein ligation product. We exemplify the protocols by generating protein kinase Akt1 with site-specific phosphorylations installed into its C-terminal tail, for kinetic kinase assays. We hope these methods will help increase the use of protein semisynthesis for elucidating the post-translational regulation of human enzymes involved in cell signaling. © 2022 Wiley Periodicals LLC Basic Protocol 1: Generation of the N-terminal protein of interest (POI) fragment containing a C-terminal thioester moiety Basic Protocol 2: Expressed protein ligation (EPL) of the protein thioester with a synthetic peptide and purification of the protein ligation product Basic Protocol 3: Semisynthesis and biochemical analysis of site-specifically phosphorylated Akt1.
Collapse
Affiliation(s)
- Marie Butts
- Department of Cancer Biology and Genetics, the Comprehensive Cancer Center, College of Medicine, The Ohio State University; Columbus, OH 43210, USA
| | - Nam Chu
- Department of Cancer Biology and Genetics, the Comprehensive Cancer Center, College of Medicine, The Ohio State University; Columbus, OH 43210, USA,Corresponding author:
| |
Collapse
|
21
|
The PTEN and ATM axis controls the G1/S cell cycle checkpoint and tumorigenesis in HER2-positive breast cancer. Cell Death Differ 2021; 28:3036-3051. [PMID: 34059798 PMCID: PMC8564521 DOI: 10.1038/s41418-021-00799-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 02/04/2023] Open
Abstract
The tumor suppressor PTEN is disrupted in a large proportion of cancers, including in HER2-positive breast cancer, where its loss is associated with resistance to therapy. Upon genotoxic stress, ataxia telangiectasia mutated (ATM) is activated and phosphorylates PTEN on residue 398. To elucidate the physiological role of this molecular event, we generated and analyzed knock-in mice expressing a mutant form of PTEN that cannot be phosphorylated by ATM (PTEN-398A). This mutation accelerated tumorigenesis in a model of HER2-positive breast cancer. Mammary tumors in bi-transgenic mice carrying MMTV-neu and Pten398A were characterized by DNA damage accumulation but reduced apoptosis. Mechanistically, phosphorylation of PTEN at position 398 is essential for the proper activation of the S phase checkpoint controlled by the PI3K-p27Kip1-CDK2 axis. Moreover, we linked these defects to the impaired ability of the PTEN-398A protein to relocalize to the plasma membrane in response to genotoxic stress. Altogether, our results uncover a novel role for ATM-dependent PTEN phosphorylation in the control of genomic stability, cell cycle progression, and tumorigenesis.
Collapse
|
22
|
The structural basis of PTEN regulation by multi-site phosphorylation. Nat Struct Mol Biol 2021; 28:858-868. [PMID: 34625746 PMCID: PMC8549118 DOI: 10.1038/s41594-021-00668-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 08/26/2021] [Indexed: 12/12/2022]
Abstract
Phosphatase and tensin homolog (PTEN) is a phosphatidylinositol-3,4,5-triphosphate (PIP3) phospholipid phosphatase that is commonly mutated or silenced in cancer. PTEN's catalytic activity, cellular membrane localization and stability are orchestrated by a cluster of C-terminal phosphorylation (phospho-C-tail) events on Ser380, Thr382, Thr383 and Ser385, but the molecular details of this multi-faceted regulation have remained uncertain. Here we use a combination of protein semisynthesis, biochemical analysis, NMR, X-ray crystallography and computational simulations on human PTEN and its sea squirt homolog, VSP, to obtain a detailed picture of how the phospho-C-tail forms a belt around the C2 and phosphatase domains of PTEN. We also visualize a previously proposed dynamic N-terminal α-helix and show that it is key for PTEN catalysis but disordered upon phospho-C-tail interaction. This structural model provides a comprehensive framework for how C-tail phosphorylation can impact PTEN's cellular functions.
Collapse
|
23
|
Jang H, Smith IN, Eng C, Nussinov R. The mechanism of full activation of tumor suppressor PTEN at the phosphoinositide-enriched membrane. iScience 2021; 24:102438. [PMID: 34113810 PMCID: PMC8169795 DOI: 10.1016/j.isci.2021.102438] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 03/15/2021] [Accepted: 04/12/2021] [Indexed: 12/13/2022] Open
Abstract
Tumor suppressor PTEN, the second most highly mutated protein in cancer, dephosphorylates signaling lipid PIP3 produced by PI3Ks. Excess PIP3 promotes cell proliferation. The mechanism at the membrane of this pivotal phosphatase is unknown hindering drug discovery. Exploiting explicit solvent simulations, we tracked full-length PTEN trafficking from the cytosol to the membrane. We observed its interaction with membranes composed of zwitterionic phosphatidylcholine, anionic phosphatidylserine, and phosphoinositides, including signaling lipids PIP2 and PIP3. We tracked its moving away from the zwitterionic and getting absorbed onto anionic membrane that harbors PIP3. We followed it localizing on microdomains enriched in signaling lipids, as PI3K does, and observed PIP3 allosterically unfolding the N-terminal PIP2 binding domain, positioning it favorably for the polybasic motif interaction with PIP2. Finally, we determined PTEN catalytic action at the membrane, all in line with experimental observations, deciphering the mechanisms of how PTEN anchors to the membrane and restrains cancer. PTEN localizes on membrane microdomains enriched in phosphoinositides, as PI3K does Full PTEN activation requires both signaling lipids, PIP2 and PIP3 Strong salt bridge interactions sustain stable PTEN membrane localization Substrate-induced P loop conformational change implicates PTEN catalytic activity
Collapse
Affiliation(s)
- Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
| | - Iris Nira Smith
- Genomic Medicine Institute, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, USA
| | - Charis Eng
- Genomic Medicine Institute, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, USA.,Center for Personalized Genetic Healthcare, Cleveland Clinic Community Care and Population Health, Cleveland, OH 44195, USA.,Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.,Germline High Risk Cancer Focus Group, Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA.,Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| |
Collapse
|
24
|
Jiang H, Dempsey DR, Cole PA. Ubiquitin Ligase Activities of WWP1 Germline Variants K740N and N745S. Biochemistry 2021; 60:357-364. [PMID: 33470109 DOI: 10.1021/acs.biochem.0c00869] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
WWP1 is an E3 ubiquitin ligase that has been reported to target the tumor suppressor lipid phosphatase PTEN. K740N and N745S are recently identified germline variants of WWP1 that have been linked to PTEN-associated cancers [Lee, Y. R., et al. (2020) N. Engl. J. Med.]. These WWP1 variants have been suggested to release WWP1 from its native autoinhibited state, thereby promoting enhanced PTEN ubiquitination as a mechanism for driving cancer. Using purified proteins and in vitro enzymatic assays, we investigate the possibility that K740N and N745S WWP1 possess enhanced ubiquitin ligase activity and demonstrate that these variants are similar to the wild type (WT) in both autoubiquitination and PTEN ubiquitination. Furthermore, K740N and N745S WWP1 show dependencies similar to those of WT in terms of allosteric activation by an engineered ubiquitin variant, upstream E2 concentration, and substrate ubiquitin concentration. Transfected WWP1 WT and mutants demonstrate comparable effects on cellular PTEN levels. These findings challenge the idea that K740N and N745S WWP1 variants promote cancer by enhanced PTEN ubiquitination.
Collapse
Affiliation(s)
- Hanjie Jiang
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States.,Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Daniel R Dempsey
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Philip A Cole
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States.,Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| |
Collapse
|
25
|
Smith SL, Pitt AR, Spickett CM. Approaches to Investigating the Protein Interactome of PTEN. J Proteome Res 2020; 20:60-77. [PMID: 33074689 DOI: 10.1021/acs.jproteome.0c00570] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The tumor suppressor phosphatase and tensin homologue (PTEN) is a redox-sensitive dual specificity phosphatase with an essential role in the negative regulation of the PI3K-AKT signaling pathway, affecting metabolic and cell survival processes. PTEN is commonly mutated in cancer, and dysregulation in the metabolism of PIP3 is implicated in other diseases such as diabetes. PTEN interactors are responsible for some functional roles of PTEN beyond the negative regulation of the PI3K pathway and are thus of great importance in cell biology. Both high-data content proteomics-based approaches and low-data content PPI approaches have been used to investigate the interactome of PTEN and elucidate further functions of PTEN. While low-data content approaches rely on co-immunoprecipitation and Western blotting, and as such require previously generated hypotheses, high-data content approaches such as affinity pull-down proteomic assays or the yeast 2-hybrid system are hypothesis generating. This review provides an overview of the PTEN interactome, including redox effects, and critically appraises the methods and results of high-data content investigations into the global interactome of PTEN. The biological significance of findings from recent studies is discussed and illustrates the breadth of cellular functions of PTEN that can be discovered by these approaches.
Collapse
Affiliation(s)
- Sarah L Smith
- School of Life and Health Sciences, Aston Triangle, Aston University, B4 7ET, Birmingham, U.K
| | - Andrew R Pitt
- School of Life and Health Sciences, Aston Triangle, Aston University, B4 7ET, Birmingham, U.K.,Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, U.K
| | - Corinne M Spickett
- School of Life and Health Sciences, Aston Triangle, Aston University, B4 7ET, Birmingham, U.K
| |
Collapse
|
26
|
Chu N, Viennet T, Bae H, Salguero A, Boeszoermenyi A, Arthanari H, Cole PA. The structural determinants of PH domain-mediated regulation of Akt revealed by segmental labeling. eLife 2020; 9:e59151. [PMID: 32744507 PMCID: PMC7438110 DOI: 10.7554/elife.59151] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/03/2020] [Indexed: 12/19/2022] Open
Abstract
Akt is a critical protein kinase that governs cancer cell growth and metabolism. Akt appears to be autoinhibited by an intramolecular interaction between its N-terminal pleckstrin homology (PH) domain and kinase domain, which is relieved by C-tail phosphorylation, but the precise molecular mechanisms remain elusive. Here, we use a combination of protein semisynthesis, NMR, and enzymological analysis to characterize structural features of the PH domain in its autoinhibited and activated states. We find that Akt autoinhibition depends on the length/flexibility of the PH-kinase linker. We identify a role for a dynamic short segment in the PH domain that appears to regulate autoinhibition and PDK1-catalyzed phosphorylation of Thr308 in the activation loop. We determine that Akt allosteric inhibitor MK2206 drives distinct PH domain structural changes compared to baseline autoinhibited Akt. These results highlight how the conformational plasticity of Akt governs the delicate control of its catalytic properties.
Collapse
Affiliation(s)
- Nam Chu
- Division of Genetics, Department of Medicine, Brigham and Women's HospitalBostonUnited States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical SchoolBostonUnited States
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of MedicineBaltimoreUnited States
| | - Thibault Viennet
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical SchoolBostonUnited States
- Department of Cancer Biology, Dana-Farber Cancer InstituteBostonUnited States
| | - Hwan Bae
- Division of Genetics, Department of Medicine, Brigham and Women's HospitalBostonUnited States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical SchoolBostonUnited States
| | - Antonieta Salguero
- Division of Genetics, Department of Medicine, Brigham and Women's HospitalBostonUnited States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical SchoolBostonUnited States
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of MedicineBaltimoreUnited States
| | - Andras Boeszoermenyi
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical SchoolBostonUnited States
- Department of Cancer Biology, Dana-Farber Cancer InstituteBostonUnited States
| | - Haribabu Arthanari
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical SchoolBostonUnited States
- Department of Cancer Biology, Dana-Farber Cancer InstituteBostonUnited States
| | - Philip A Cole
- Division of Genetics, Department of Medicine, Brigham and Women's HospitalBostonUnited States
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical SchoolBostonUnited States
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of MedicineBaltimoreUnited States
| |
Collapse
|
27
|
Strunk BS, Steinfeld N, Lee S, Jin N, Muñoz-Rivera C, Meeks G, Thomas A, Akemann C, Mapp AK, MacGurn JA, Weisman LS. Roles for a lipid phosphatase in the activation of its opposing lipid kinase. Mol Biol Cell 2020; 31:1835-1845. [PMID: 32583743 PMCID: PMC7525815 DOI: 10.1091/mbc.e18-09-0556] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Fig4 is a phosphoinositide phosphatase that converts PI3,5P2 to PI3P. Paradoxically, mutation of Fig4 results in lower PI3,5P2, indicating that Fig4 is also required for PI3,5P2 production. Fig4 promotes elevation of PI3,5P2, in part, through stabilization of a protein complex that includes its opposing lipid kinase, Fab1, and the scaffold protein Vac14. Here we show that multiple regions of Fig4 contribute to its roles in the elevation of PI3,5P2: its catalytic site, an N-terminal disease-related surface, and a C-terminal region. We show that mutation of the Fig4 catalytic site enhances the formation of the Fab1-Vac14-Fig4 complex, and reduces the ability to elevate PI3,5P2. This suggests that independent of its lipid phosphatase function, the active site plays a role in the Fab1-Vac14-Fig4 complex. We also show that the N-terminal disease-related surface contributes to the elevation of PI3,5P2 and promotes Fig4 association with Vac14 in a manner that requires the Fig4 C-terminus. We find that the Fig4 C-terminus alone interacts with Vac14 in vivo and retains some functions of full-length Fig4. Thus, a subset of Fig4 functions are independent of its phosphatase domain and at least three regions of Fig4 play roles in the function of the Fab1-Vac14-Fig4 complex.
Collapse
Affiliation(s)
- Bethany S Strunk
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
- Department of Biology, Trinity University, San Antonio, TX 78212
| | - Noah Steinfeld
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109
| | - Sora Lee
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37232
| | - Natsuko Jin
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
| | | | - Garrison Meeks
- Department of Biology, Trinity University, San Antonio, TX 78212
| | - Asha Thomas
- Department of Biology, Trinity University, San Antonio, TX 78212
| | - Camille Akemann
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
| | - Anna K Mapp
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
| | - Jason A MacGurn
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37232
| | - Lois S Weisman
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109
| |
Collapse
|
28
|
PTEN activation contributes to neuronal and synaptic engulfment by microglia in tauopathy. Acta Neuropathol 2020; 140:7-24. [PMID: 32236736 PMCID: PMC7300099 DOI: 10.1007/s00401-020-02151-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 12/13/2022]
Abstract
Phosphatase and tensin homolog (PTEN) regulates synaptic density in development; however, whether PTEN also regulates synapse loss in a neurodegenerative disorder such as frontotemporal lobar degeneration with Tau deposition (FTLD-Tau) has not been explored. Here, we found that pathological Tau promotes early activation of PTEN, which precedes apoptotic caspase-3 cleavage in the rTg4510 mouse model of FTLD-Tau. We further demonstrate increased synaptic and neuronal exposure of the apoptotic signal phosphatidylserine that tags neuronal structures for microglial uptake, thereby linking PTEN activation to synaptic and neuronal structure elimination. By applying pharmacological inhibition of PTEN's protein phosphatase activity, we observed that microglial uptake can be decreased in Tau transgenic mice. Finally, we reveal a dichotomous relationship between PTEN activation and age in FTLD-Tau patients and healthy controls. Together, our findings suggest that in tauopathy, PTEN has a role in the synaptotoxicity of pathological Tau and promotes microglial removal of affected neuronal structures.
Collapse
|
29
|
Posttranslational Regulation and Conformational Plasticity of PTEN. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a036095. [PMID: 31932468 DOI: 10.1101/cshperspect.a036095] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a tumor suppressor that is frequently down-modulated in human cancer. PTEN inhibits the phosphatidylinositol 3-phosphate kinase (PI3K)/AKT pathway through its lipid phosphatase activity. Multiple PI3K/AKT-independent actions of PTEN, protein-phosphatase activities and functions within the nucleus have also been described. PTEN, therefore, regulates many cellular processes including cell proliferation, survival, genomic integrity, polarity, migration, and invasion. Even a modest decrease in the functional dose of PTEN may promote cancer development. Understanding the molecular and cellular mechanisms that regulate PTEN protein levels and function, and how these may go awry in cancer contexts, is, therefore, key to fully understanding the role of PTEN in tumorigenesis. Here, we discuss current knowledge on posttranslational control and conformational plasticity of PTEN, as well as therapeutic possibilities toward reestablishment of PTEN tumor-suppressor activity in cancer.
Collapse
|
30
|
Rainey L, Deevi RK, McClements J, Khawaja H, Watson CJ, Roudier M, Van Schaeybroeck S, Campbell FC. Fundamental control of grade-specific colorectal cancer morphology by Src regulation of ezrin-centrosome engagement. J Pathol 2020; 251:310-322. [PMID: 32315081 DOI: 10.1002/path.5452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 02/27/2020] [Accepted: 04/07/2020] [Indexed: 11/11/2022]
Abstract
The phenotypic spectrum of colorectal cancer (CRC) is remarkably diverse, with seemingly endless variations in cell shape, mitotic figures and multicellular configurations. Despite this morphological complexity, histological grading of collective phenotype patterns provides robust prognostic stratification in CRC. Although mechanistic understanding is incomplete, previous studies have shown that the cortical protein ezrin controls diversification of cell shape, mitotic figure geometry and multicellular architecture, in 3D organotypic CRC cultures. Because ezrin is a substrate of Src tyrosine kinase that is frequently overexpressed in CRC, we investigated Src regulation of ezrin and morphogenic growth in 3D CRC cultures. Here we show that Src perturbations disrupt CRC epithelial spatial organisation. Aberrant Src activity suppresses formation of the cortical ezrin cap that anchors interphase centrosomes. In CRC cells with a normal centrosome number, these events lead to mitotic spindle misorientation, perturbation of cell cleavage, abnormal epithelial stratification, apical membrane misalignment, multilumen formation and evolution of cribriform multicellular morphology, a feature of low-grade cancer. In isogenic CRC cells with centrosome amplification, aberrant Src signalling promotes multipolar mitotic spindle formation, pleomorphism and morphological features of high-grade cancer. Translational studies in archival human CRC revealed associations between Src intensity, multipolar mitotic spindle frequency and high-grade cancer morphology. Collectively, our study reveals Src regulation of CRC morphogenic growth via ezrin-centrosome engagement and uncovers combined perturbations underlying transition to high-grade CRC morphology. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Collapse
Affiliation(s)
- Lisa Rainey
- Centre for Cancer Research and Cell Biology, Queen's University Belfast and Belfast Health and Social Care Trust, Belfast, UK
| | - Ravi K Deevi
- Centre for Cancer Research and Cell Biology, Queen's University Belfast and Belfast Health and Social Care Trust, Belfast, UK
| | - Jane McClements
- Centre for Cancer Research and Cell Biology, Queen's University Belfast and Belfast Health and Social Care Trust, Belfast, UK
| | - Hajrah Khawaja
- Centre for Cancer Research and Cell Biology, Queen's University Belfast and Belfast Health and Social Care Trust, Belfast, UK
| | - Chris J Watson
- Wellcome Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, UK
| | - Martine Roudier
- Molecular Pathology Laboratory, AstraZeneca Oncology Translational Science, Cambridge, UK
| | - Sandra Van Schaeybroeck
- Centre for Cancer Research and Cell Biology, Queen's University Belfast and Belfast Health and Social Care Trust, Belfast, UK
| | - Frederick C Campbell
- Centre for Cancer Research and Cell Biology, Queen's University Belfast and Belfast Health and Social Care Trust, Belfast, UK
| |
Collapse
|
31
|
Jiang H, D'Agostino GD, Cole PA, Dempsey DR. Selective protein N-terminal labeling with N-hydroxysuccinimide esters. Methods Enzymol 2020; 639:333-353. [PMID: 32475408 DOI: 10.1016/bs.mie.2020.04.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In order to gain detailed insight into the biochemical behavior of proteins, researchers have developed chemical tools to incorporate new functionality into proteins beyond the canonical 20 amino acids. Important considerations regarding effective chemical modification of proteins include chemoselectivity, near stoichiometric labeling, and reaction conditions that maintain protein stability. Taking these factors into account, we discuss an N-terminal labeling strategy that employs a simple two-step "one-pot" method using N-hydroxysuccinimide (NHS) esters. The first step converts a R-NHS ester into a more chemoselective R-thioester. The second step reacts the in situ generated R-thioester with a protein that harbors an N-terminal cysteine to generate a new amide bond. This labeling reaction is selective for the N-terminus with high stoichiometry. Herein, we provide a detailed description of this method and further highlight its utility with a large protein (>100kDa) and labeling with a commonly used cyanine dye.
Collapse
Affiliation(s)
- Hanjie Jiang
- Division of Genetics, Brigham and Women's Hospital, Departments of Medicine and Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Gabriel D D'Agostino
- Division of Genetics, Brigham and Women's Hospital, Departments of Medicine and Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Philip A Cole
- Division of Genetics, Brigham and Women's Hospital, Departments of Medicine and Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Daniel R Dempsey
- Division of Genetics, Brigham and Women's Hospital, Departments of Medicine and Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States.
| |
Collapse
|
32
|
Skelton PD, Stan RV, Luikart BW. The Role of PTEN in Neurodevelopment. MOLECULAR NEUROPSYCHIATRY 2020; 5:60-71. [PMID: 32399470 PMCID: PMC7206585 DOI: 10.1159/000504782] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 11/13/2019] [Indexed: 12/11/2022]
Abstract
PTEN is a lipid and protein phosphatase that regulates cell growth and survival. Mutations to PTEN are highly penetrant for autism spectrum disorder (ASD). Here, we briefly review the evidence linking PTEN mutations to ASD and the mouse models that have been used to study the role of PTEN in neurodevelopment. We then focus on the cellular phenotypes associated with PTEN loss in neurons, highlighting the role PTEN plays in neuronal proliferation, migration, survival, morphology, and plasticity.
Collapse
Affiliation(s)
- Patrick D. Skelton
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Radu V. Stan
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Bryan W. Luikart
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| |
Collapse
|
33
|
Abstract
Protein semisynthesis-defined herein as the assembly of a protein from a combination of synthetic and recombinant fragments-is a burgeoning field of chemical biology that has impacted many areas in the life sciences. In this review, we provide a comprehensive survey of this area. We begin by discussing the various chemical and enzymatic methods now available for the manufacture of custom proteins containing noncoded elements. This section begins with a discussion of methods that are more chemical in origin and ends with those that employ biocatalysts. We also illustrate the commonalities that exist between these seemingly disparate methods and show how this is allowing for the development of integrated chemoenzymatic methods. This methodology discussion provides the technical foundation for the second part of the review where we cover the great many biological problems that have now been addressed using these tools. Finally, we end the piece with a short discussion on the frontiers of the field and the opportunities available for the future.
Collapse
Affiliation(s)
| | - Tom W. Muir
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, New Jersey 08544, United States
| |
Collapse
|
34
|
Abstract
The tumor suppressor phosphatase and tensin homolog on chromosome 10 (PTEN) is a tightly regulated enzyme responsible for dephosphorylating the progrowth lipid messenger molecule phosphatidylinositol 3,4,5-trisphosphate (PIP3) on the plasma membrane. The carboxy-terminal tail (CTT) of PTEN is key for regulation of the enzyme. When phosphorylated, the unstructured CTT interacts with the phosphatase-C2 superdomain to inactivate the enzyme by preventing membrane association. PTEN mutations associated with cancer also inactivate the enzyme. Alternate translation-initiation sites generate extended isoforms of PTEN, such as PTEN-L that has multiple roles in cells. The extended amino-terminal region bears a signal sequence and a polyarginine sequence to facilitate exit from and entry into cells, respectively, and a membrane-binding helix that activates the enzyme. This amino-terminal region also facilitates mitochondrial and nucleolar localization. This review explores PTEN structure and its impact on localization and regulation.
Collapse
|
35
|
Henager SH, Henriquez S, Dempsey DR, Cole PA. Analysis of Site-Specific Phosphorylation of PTEN by Using Enzyme-Catalyzed Expressed Protein Ligation. Chembiochem 2020; 21:64-68. [PMID: 31206229 PMCID: PMC7012368 DOI: 10.1002/cbic.201900316] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Indexed: 01/05/2023]
Abstract
The activity and localization of PTEN, a tumor suppressor lipid phosphatase that converts the phospholipid PIP3 to PIP2, is governed in part by phosphorylation on a cluster of four Ser and Thr residues near the C terminus. Prior enzymatic characterization of the four monophosphorylated (1p) PTENs by using classical expressed protein ligation (EPL) was complicated by the inclusion of a non-native Cys at the ligation junction (aa379), which may alter the properties of the semisynthetic protein. Here, we apply subtiligase-mediated EPL to create wt 1p-PTENs. These PTENs are more autoinhibited than previously appreciated, consistent with the role of Tyr379 in driving autoinhibition. Alkaline phosphatase sensitivity analysis revealed that these autoinhibited 1p conformations are kinetically labile. In contrast to the Cys mutant 1p-PTENs, which are poorly recognized by an anti-phospho-PTEN antibody, three of the four wt 1p-PTENs are recognized by a commonly used anti-phospho-PTEN antibody.
Collapse
Affiliation(s)
- Samuel H Henager
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, 725 N. Wolfe Street, Baltimore, MD, 21205, USA
| | - Stephanie Henriquez
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, 725 N. Wolfe Street, Baltimore, MD, 21205, USA
| | - Daniel R Dempsey
- Division of Genetics, Departments of Medicine and Biological Chemistry and Molecular Pharmacology, Harvard Medical School and Brigham and Women's Hospital, 25 Shattuck Street, Boston, MA, 02115, USA
| | - Philip A Cole
- Division of Genetics, Departments of Medicine and Biological Chemistry and Molecular Pharmacology, Harvard Medical School and Brigham and Women's Hospital, 25 Shattuck Street, Boston, MA, 02115, USA
| |
Collapse
|
36
|
Abstract
Expressed protein ligation is a method of protein semisynthesis and typically involves the reaction of recombinant protein C-terminal thioesters with N-cysteine containing synthetic peptides in a chemoselective ligation. The recombinant protein C-terminal thioesters are produced by exploiting the action of nature's inteins which are protein modules that catalyze protein splicing. This chapter discusses the basic principles of expressed protein ligation and recent advances and applications in this protein semisynthesis field. Comparative strengths and weaknesses of the method and future challenges are highlighted.
Collapse
Affiliation(s)
- Zhipeng A Wang
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Philip A Cole
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
37
|
Pulido R, Mingo J, Gaafar A, Nunes-Xavier CE, Luna S, Torices L, Angulo JC, López JI. Precise Immunodetection of PTEN Protein in Human Neoplasia. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a036293. [PMID: 31501265 DOI: 10.1101/cshperspect.a036293] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PTEN is a major tumor-suppressor protein whose expression and biological activity are frequently diminished in sporadic or inherited cancers. PTEN gene deletion or loss-of-function mutations favor tumor cell growth and are commonly found in clinical practice. In addition, diminished PTEN protein expression is also frequently observed in tumor samples from cancer patients in the absence of PTEN gene alterations. This makes PTEN protein levels a potential biomarker parameter in clinical oncology, which can guide therapeutic decisions. The specific detection of PTEN protein can be achieved by using highly defined anti-PTEN monoclonal antibodies (mAbs), characterized with precision in terms of sensitivity for the detection technique, specificity for PTEN binding, and constraints of epitope recognition. This is especially relevant taking into consideration that PTEN is highly targeted by mutations and posttranslational modifications, and different PTEN protein isoforms exist. The precise characterization of anti-PTEN mAb reactivity is an important step in the validation of these reagents as diagnostic and prognostic tools in clinical oncology, including their routine use in analytical immunohistochemistry (IHC). Here, we review the current status on the use of well-defined anti-PTEN mAbs for PTEN immunodetection in the clinical context and discuss their potential usefulness and limitations for a more precise cancer diagnosis and patient benefit.
Collapse
Affiliation(s)
- Rafael Pulido
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao 48011, Spain
| | - Janire Mingo
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain
| | - Ayman Gaafar
- Department of Pathology, Cruces University Hospital, Barakaldo 48903, Spain
| | - Caroline E Nunes-Xavier
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain.,Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital Radiumhospitalet, Oslo N-0310, Norway
| | - Sandra Luna
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain
| | - Leire Torices
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain
| | - Javier C Angulo
- Department of Urology, University Hospital of Getafe, Getafe, Madrid 28904, Spain.,Clinical Department, European University of Madrid, Laureate Universities, Madrid 28904, Spain
| | - José I López
- Biocruces Bizkaia Health Research Institute, Barakaldo 48903, Spain.,Department of Pathology, Cruces University Hospital, Barakaldo 48903, Spain.,University of the Basque Country, Leioa 48940, Spain
| |
Collapse
|
38
|
Abstract
Subtiligase-catalyzed peptide ligation is a powerful approach for site-specific protein bioconjugation, synthesis and semisynthesis of proteins and peptides, and chemoproteomic analysis of cellular N termini. Here, we provide a comprehensive review of the subtiligase technology, including its development, applications, and impacts on protein science. We highlight key advantages and limitations of the tool and compare it to other peptide ligase enzymes. Finally, we provide a perspective on future applications and challenges and how they may be addressed.
Collapse
Affiliation(s)
- Amy M Weeks
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California 94143, United States
| | - James A Wells
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California 94143, United States.,Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, California 94143, United States
| |
Collapse
|
39
|
Palumbo E, Zhao B, Xue B, Uversky VN, Davé V. Analyzing aggregation propensities of clinically relevant PTEN mutants: a new culprit in pathogenesis of cancer and other PTENopathies. J Biomol Struct Dyn 2019; 38:2253-2266. [PMID: 31232187 DOI: 10.1080/07391102.2019.1630005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
While studies on pathological protein aggregation are largely limited to neurodegenerative disease, emerging evidence suggests that other diseases are also associated with pathogenic protein aggregation. For example, tumor suppressor protein p53, and its mutant conformers, undergo protein aggregation, exacerbating the cancer phenotype. These findings raise the possibility that inactivation of tumor suppressors via protein aggregation may participate in cancer and other disease pathologies. Since tumor suppressor protein PTEN has similar functions to p53, and is mutated in multiple diseases, we examined the aggregation propensity of PTEN wild-type and 1523 clinically relevant PTEN mutants. Applying computational tools to PTEN mutation databases revealed that PTEN wild-type protein can aggregate under physiological conditions, and 274 distinct PTEN mutants had increased aggregation propensity. To understand the mechanism underlying PTEN conformer aggregation, we analyzed the physicochemical properties of these 274 PTEN mutants and defined their aggregation potential. We conclude that increased aggregation propensity of select PTEN mutants may contribute to disease phenotypes. Our studies have built the foundation for interrogating the aggregation potential of these select mutants in cancers and in PTENopathies. Elucidating the pathogenic mechanisms associated with aggregation-prone PTEN conformers will aid in developing therapies that target PTEN-aggregates in multiple diseases.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Emily Palumbo
- Department of Pathology and Cell Biology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Bi Zhao
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, USA
| | - Bin Xue
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine, Morsani College of Medicine, Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, USA.,Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Vrushank Davé
- Department of Pathology and Cell Biology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| |
Collapse
|
40
|
Bazzichetto C, Conciatori F, Pallocca M, Falcone I, Fanciulli M, Cognetti F, Milella M, Ciuffreda L. PTEN as a Prognostic/Predictive Biomarker in Cancer: An Unfulfilled Promise? Cancers (Basel) 2019; 11:cancers11040435. [PMID: 30925702 PMCID: PMC6520939 DOI: 10.3390/cancers11040435] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 03/22/2019] [Accepted: 03/25/2019] [Indexed: 12/22/2022] Open
Abstract
Identifying putative biomarkers of clinical outcomes in cancer is crucial for successful enrichment, and for the selection of patients who are the most likely to benefit from a specific therapeutic approach. Indeed, current research in personalized cancer therapy focuses on the possibility of identifying biomarkers that predict prognosis, sensitivity or resistance to therapies. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a tumor suppressor gene that regulates several crucial cell functions such as proliferation, survival, genomic stability and cell motility through both enzymatic and non-enzymatic activities and phosphatidylinositol 3-kinase (PI3K)-dependent and -independent mechanisms. Despite its undisputed role as a tumor suppressor, assessment of PTEN status in sporadic human tumors has yet to provide clinically robust prognostic, predictive or therapeutic information. This is possibly due to the exceptionally complex regulation of PTEN function, which involves genetic, transcriptional, post-transcriptional and post-translational events. This review shows a brief summary of the regulation and function of PTEN and discusses its controversial aspects as a prognostic/predictive biomarker.
Collapse
Affiliation(s)
- Chiara Bazzichetto
- Medical Oncology 1, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
- Department of Molecular Medicine, University of Rome, La Sapienza, Rome 00185, Italy.
| | - Fabiana Conciatori
- Medical Oncology 1, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
| | - Matteo Pallocca
- SAFU, Department of Research, Advanced Diagnostics, and Technological Innovation, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
| | - Italia Falcone
- Medical Oncology 1, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
| | - Maurizio Fanciulli
- SAFU, Department of Research, Advanced Diagnostics, and Technological Innovation, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
| | - Francesco Cognetti
- Medical Oncology 1, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
| | - Michele Milella
- Section of Oncology, Department of Medicine, University of Verona School of Medicine and Verona University Hospital Trust, Verona 37126, Italy.
| | - Ludovica Ciuffreda
- Medical Oncology 1, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
- SAFU, Department of Research, Advanced Diagnostics, and Technological Innovation, IRCCS - Regina Elena National Cancer Institute, Rome 00144, Italy.
| |
Collapse
|
41
|
Naderali E, Khaki AA, Rad JS, Ali-Hemmati A, Rahmati M, Charoudeh HN. Regulation and modulation of PTEN activity. Mol Biol Rep 2018; 45:2869-2881. [PMID: 30145641 DOI: 10.1007/s11033-018-4321-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 08/20/2018] [Indexed: 01/04/2023]
Abstract
PTEN (Phosphatase and tensin homolog deleted on chromosome ten) is a tumor suppressor that is frequently mutated in most human cancers. PTEN is a lipid and protein phosphatase that antagonizes PI3K/AKT pathway through lipid phosphatase activity at the plasma membrane. More recent studies showed that, in addition to the putative role of PTEN as a PI(3,4,5)P3 3-phosphatase, it is a PI(3,4)P2 3-phosphatase during stimulation of class I PI3K signaling pathway by growth factor. Although PTEN tumor suppressor function via it's lipid phosphatase activity occurs primarily in the plasma membrane, it can also be found in the nucleus, in cytoplasmic organelles and extracellular space. PTEN has also shown phosphatase independent functions in the nucleus. PTEN can exit from the cell through exosomal export or secretion and has a tumor suppressor function in adjacent cells. PTEN has a critical role in growth, the cell cycle, protein synthesis, survival, DNA repair and migration. Understanding the regulation of PTEN function, activity, stability, localization and its dysregulation outcomes and also the intracellular and extracellular role of PTEN and paracrine role of PTEN-L in tumor cells as an exogenous therapeutic agent can help to improve clinical conceptualization and treatment of cancer.
Collapse
Affiliation(s)
- Elahe Naderali
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Afshin Khaki
- Department of Anatomical sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Jafar Soleymani Rad
- Department of Anatomical sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Ali-Hemmati
- Department of Anatomical sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Rahmati
- Department of Clinical Biochemistry Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hojjatollah Nozad Charoudeh
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. .,Cell Therapy Research Laboratory, Drug Applied Research Center, Tabriz University of Medical Sciences, P.O. Box: 51656-65811, Tabriz, Iran.
| |
Collapse
|
42
|
Fricano-Kugler CJ, Getz SA, Williams MR, Zurawel AA, DeSpenza T, Frazel PW, Li M, O’Malley AJ, Moen EL, Luikart BW. Nuclear Excluded Autism-Associated Phosphatase and Tensin Homolog Mutations Dysregulate Neuronal Growth. Biol Psychiatry 2018; 84:265-277. [PMID: 29373119 PMCID: PMC5984669 DOI: 10.1016/j.biopsych.2017.11.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 11/01/2017] [Accepted: 11/16/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Phosphatase and tensin homolog (PTEN) negatively regulates downstream protein kinase B signaling, resulting in decreased cellular growth and proliferation. PTEN is mutated in a subset of children with autism spectrum disorder (ASD); however, the mechanism by which specific point mutations alter PTEN function is largely unknown. Here, we assessed how ASD-associated single-nucleotide variations in PTEN (ASD-PTEN) affect function. METHODS We used viral-mediated molecular substitution of human PTEN into Pten knockout mouse neurons and assessed neuronal morphology to determine the functional impact of ASD-PTEN. We employed molecular cloning to examine how PTEN's stability, subcellular localization, and catalytic activity affect neuronal growth. RESULTS We identified a set of ASD-PTEN mutations displaying altered lipid phosphatase function and subcellular localization. We demonstrated that wild-type PTEN can rescue the neuronal hypertrophy, while PTEN H93R, F241S, D252G, W274L, N276S, and D326N failed to rescue this hypertrophy. A subset of these mutations lacked nuclear localization, prompting us to examine the role of nuclear PTEN in regulating neuronal growth. We found that nuclear PTEN alone is sufficient to regulate soma size. Furthermore, forced localization of the D252G and W274L mutations into the nucleus partially restores regulation of soma size. CONCLUSIONS ASD-PTEN mutations display decreased stability, catalytic activity, and/or altered subcellular localization. Mutations lacking nuclear localization uncover a novel mechanism whereby lipid phosphatase activity in the nucleus can regulate mammalian target of rapamycin signaling and neuronal growth.
Collapse
Affiliation(s)
- Catherine J. Fricano-Kugler
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756
| | - Stephanie A. Getz
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756
| | - Michael R. Williams
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756
| | - Ashley A. Zurawel
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756
| | - Tyrone DeSpenza
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756
| | - Paul W. Frazel
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756
| | - Meijie Li
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756
| | - Alistair J. O’Malley
- The Dartmouth Institute for Health Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA,Department of Biomedical Data Science, The Dartmouth Institute for Health Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Erika L. Moen
- The Dartmouth Institute for Health Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Bryan W. Luikart
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03756,Corresponding Author-
| |
Collapse
|
43
|
Chu N, Salguero AL, Liu AZ, Chen Z, Dempsey DR, Ficarro SB, Alexander WM, Marto JA, Li Y, Amzel LM, Gabelli SB, Cole PA. Akt Kinase Activation Mechanisms Revealed Using Protein Semisynthesis. Cell 2018; 174:897-907.e14. [PMID: 30078705 DOI: 10.1016/j.cell.2018.07.003] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 05/15/2018] [Accepted: 07/03/2018] [Indexed: 11/30/2022]
Abstract
Akt is a critical protein kinase that drives cancer proliferation, modulates metabolism, and is activated by C-terminal phosphorylation. The current structural model for Akt activation by C-terminal phosphorylation has centered on intramolecular interactions between the C-terminal tail and the N lobe of the kinase domain. Here, we employ expressed protein ligation to produce site-specifically phosphorylated forms of purified Akt1 that are well suited for mechanistic analysis. Using biochemical, crystallographic, and cellular approaches, we determine that pSer473-Akt activation is driven by an intramolecular interaction between the C-tail and the pleckstrin homology (PH)-kinase domain linker that relieves PH domain-mediated Akt1 autoinhibition. Moreover, dual phosphorylation at Ser477/Thr479 activates Akt1 through a different allosteric mechanism via an apparent activation loop interaction that reduces autoinhibition by the PH domain and weakens PIP3 affinity. These results provide a new framework for understanding how Akt is controlled in cell signaling and suggest distinct functions for differentially modified Akt forms.
Collapse
Affiliation(s)
- Nam Chu
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Antonieta L Salguero
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Albert Z Liu
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Zan Chen
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Daniel R Dempsey
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Scott B Ficarro
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - William M Alexander
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Jarrod A Marto
- Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute, Boston, MA 02115, USA; Department of Oncologic Pathology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yana Li
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - L Mario Amzel
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Sandra B Gabelli
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
| | - Philip A Cole
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
| |
Collapse
|
44
|
Pardhi TR, Patel MS, Sudarsanam V, Vasu KK. Design, synthesis, and evaluation of 4,5,6,7-tetrahydrobenzo[ d]thiazole-based novel dual kinase inhibitors of CK2 and GSK3β. MEDCHEMCOMM 2018; 9:1472-1490. [PMID: 30288222 DOI: 10.1039/c8md00321a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 07/25/2018] [Indexed: 01/07/2023]
Abstract
Casein kinase 2 (CK2) and glycogen synthase kinase-3beta (GSK3β) are responsible for the phosphorylation of a tumor suppressor protein (PTEN) in a cooperative manner which causes its deactivation. Thus, it is essential to inhibit both kinases simultaneously to prevent PTEN deactivation more efficiently. In this study, we have designed a novel lead from Hit15 which was identified in silico as a dual kinase inhibitor against CK2 and GSK3β through our previous study. The dataset of structural analogs of the lead was designed and confirmed by pharmacophore mapping and molecular docking. The screened analogs were considered further and a series of "tetrahydrobenzo[d]thiazoles" were synthesized. Compound 1g has shown highest dual kinase inhibitory activity at a concentration of 1.9 μM against CK2 and 0.67 μM against GSK3β. Our results suggest that the presence of a carboxyl group at the meta position of the phenyl ring plays a vital role in dual kinase inhibition.
Collapse
Affiliation(s)
- Triveni R Pardhi
- Department of Natural Products , National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad , Opp. Air force station, Palaj , Gandhinagar-382355 , Gujarat , India . ; ; Tel: +917927439375
| | - Manishkumar S Patel
- Department of Biotechnology , National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad , Gandhinagar-382355 , Gujarat , India
| | - V Sudarsanam
- Department of Medicinal Chemistry , B. V. Patel Pharmaceutical Education & Research Development (PERD) Centre , Ahmedabad-380054 , Gujarat , India .
| | - Kamala K Vasu
- Department of Natural Products , National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad , Opp. Air force station, Palaj , Gandhinagar-382355 , Gujarat , India . ; ; Tel: +917927439375.,Department of Medicinal Chemistry , B. V. Patel Pharmaceutical Education & Research Development (PERD) Centre , Ahmedabad-380054 , Gujarat , India .
| |
Collapse
|
45
|
Dempsey DR, Jiang H, Kalin JH, Chen Z, Cole PA. Site-Specific Protein Labeling with N-Hydroxysuccinimide-Esters and the Analysis of Ubiquitin Ligase Mechanisms. J Am Chem Soc 2018; 140:9374-9378. [PMID: 30016585 DOI: 10.1021/jacs.8b05098] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
N-Hydroxysuccinimide (NHS)-esters are widely used to label proteins nonselectively on free amino groups. Such broad labeling can be disadvantageous because it can interfere with protein structure or function and because stoichiometry is poorly controlled. Here we describe a simple method to transform NHS-esters into site-specific protein labeling on N-terminal Cys residues. MESNA addition converts NHS-esters to chemoselective thioesters for N-Cys modification. This labeling strategy was applied to clarify mechanistic features of the ubiquitin E3 ligase WWP2 including its interaction with one of its substrates, the tumor suppressor PTEN, as well as its autoubiquitination molecularity. We propose that this convenient protein labeling strategy will allow for an expanded application of NHS-esters in biochemical investigation.
Collapse
Affiliation(s)
- Daniel R Dempsey
- Division of Genetics, Departments of Medicine and Biological Chemistry and Molecular Pharmacology , Harvard Medical School and Brigham and Women's Hospital , Boston , Massachusetts 02115 , United States
| | - Hanjie Jiang
- Department of Pharmacology and Molecular Sciences , Johns Hopkins School of Medicine , Baltimore , Maryland 21205 , United States
| | - Jay H Kalin
- Division of Genetics, Departments of Medicine and Biological Chemistry and Molecular Pharmacology , Harvard Medical School and Brigham and Women's Hospital , Boston , Massachusetts 02115 , United States
| | - Zan Chen
- Department of Pharmacology and Molecular Sciences , Johns Hopkins School of Medicine , Baltimore , Maryland 21205 , United States
| | - Philip A Cole
- Division of Genetics, Departments of Medicine and Biological Chemistry and Molecular Pharmacology , Harvard Medical School and Brigham and Women's Hospital , Boston , Massachusetts 02115 , United States.,Department of Pharmacology and Molecular Sciences , Johns Hopkins School of Medicine , Baltimore , Maryland 21205 , United States
| |
Collapse
|
46
|
Dempsey DR, Cole PA. Protein Chemical Approaches to Understanding PTEN Lipid Phosphatase Regulation. Methods Enzymol 2018; 607:405-422. [PMID: 30149868 DOI: 10.1016/bs.mie.2018.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
Since the discovery of C-tail phosphorylation of PTEN almost 20 years ago, much progress has been made in understanding its regulatory influences on the cellular function of PTEN. Phosphorylation of Ser380, Thr382, Thr383, and Ser385 drives a PTEN conformational change from an open to closed state where catalytic function is impaired, plasma membrane binding is reduced, and cellular stability is enhanced. Despite these advances, a detailed structural and mechanistic model of how these phosphorylations impact PTEN function is lacking. We discuss here several recent approaches to analyzing PTEN phosphorylation and highlight several insights that have come from this work. We also discuss remaining challenges for the PTEN regulation field and potential directions for future research.
Collapse
Affiliation(s)
- Daniel R Dempsey
- Division of Genetics, Brigham and Women's Hospital, Boston, MA, United States; Department of Medicine, Harvard Medical School, Boston, MA, United States; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Philip A Cole
- Division of Genetics, Brigham and Women's Hospital, Boston, MA, United States; Department of Medicine, Harvard Medical School, Boston, MA, United States; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, United States.
| |
Collapse
|
47
|
Breuksch I, Welter J, Bauer HK, Enklaar T, Frees S, Thüroff JW, Hasenburg A, Prawitt D, Brenner W. In renal cell carcinoma the PTEN splice variant PTEN-Δ shows similar function as the tumor suppressor PTEN itself. Cell Commun Signal 2018; 16:35. [PMID: 29954386 PMCID: PMC6025732 DOI: 10.1186/s12964-018-0247-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 06/14/2018] [Indexed: 12/24/2022] Open
Abstract
Background Loss of PTEN is involved in tumor progression of several tumor entities including renal cell carcinoma (RCC). During the translation process PTEN generates a number of splice variants, including PTEN-Δ. We analyzed the impact of PTEN-Δ in RCC progression. Methods In specimens of RCC patients the expression of PTEN-Δ and PTEN was quantified. The PTEN expressing RCC cell line A498 and the PTEN deficient 786-O cell line were stably transfected with the PTEN-Δ or PTEN transcript. In Caki-1 cells that highly express PTEN-Δ, this isoform was knocked down by siRNA. Cell migration, adhesion, apoptosis and signaling pathways activities were consequently analyzed in vitro. Results Patients with a higher PTEN-Δ expression had a longer lymph node metastasis free and overall survival. In RCC specimens, the PTEN-Δ expression correlated with the PTEN expression. PTEN-Δ as well as PTEN induced a reduced migration when using extracellular matrix (ECM) compounds as chemotaxins. This effect was confirmed by knockdown of PTEN-Δ, inducing an enhanced migration. Likewise a decreased adhesion on these ECM components could be shown in PTEN-Δ and PTEN transfected cells. The apoptosis rate was slightly increased by PTEN-Δ. In a phospho-kinase array and Western blot analyses a consequently reduced activity of AKT, p38 and JNK could be shown. Conclusions We could show that the PTEN splice variant PTEN-Δ acts similar to PTEN in a tumor suppressive manner, suggesting synergistic effects of the two isoforms. The impact of PTEN-Δ in context of tumor progression should thus be taken into account when generating new therapeutic options targeting PTEN signaling in RCC. Electronic supplementary material The online version of this article (10.1186/s12964-018-0247-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Ines Breuksch
- Department of Gynecology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany.,Department of Urology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Jonas Welter
- Department of Urology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Heide-Katharina Bauer
- Department of Gynecology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Thorsten Enklaar
- Department of Pediatrics, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Sebastian Frees
- Department of Urology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Joachim W Thüroff
- Department of Urology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Annette Hasenburg
- Department of Gynecology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Dirk Prawitt
- Department of Pediatrics, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Walburgis Brenner
- Department of Gynecology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany. .,Department of Urology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany.
| |
Collapse
|
48
|
Sugiki T, Egawa D, Kumagai K, Kojima C, Fujiwara T, Takeuchi K, Shimada I, Hanada K, Takahashi H. Phosphoinositide binding by the PH domain in ceramide transfer protein (CERT) is inhibited by hyperphosphorylation of an adjacent serine-repeat motif. J Biol Chem 2018; 293:11206-11217. [PMID: 29848549 DOI: 10.1074/jbc.ra118.002465] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 05/24/2018] [Indexed: 12/13/2022] Open
Abstract
Sphingolipids such as ceramide are important constituents of cell membranes. The ceramide transfer protein (CERT) moves ceramide from the endoplasmic reticulum to the Golgi apparatus in a nonvesicular manner. Hyperphosphorylation of the serine-repeat motif (SRM) adjacent to the pleckstrin homology (PH) domain of CERT down-regulates the inter-organelle ceramide transport function of CERT. However, the mechanistic details of this down-regulation remain elusive. Using solution NMR and binding assays, we herein show that a hyperphosphorylation-mimetic CERT variant in which 10 serine/threonine residues of SRM had been replaced with glutamate residues (the 10E variant) displays an intramolecular interaction between SRM and positively charged regions of the PH domain, which are involved in the binding of this domain to phosphatidylinositol 4-monophosphate (PI4P). Of note, the binding of the PH domain to PI4P-embedded membranes was attenuated by the SRM 10E substitutions in cell-free assays. Moreover, the 10E substitutions reduced the Golgi-targeting activity of the PH-SRM construct in living cells. These results indicate that hyperphosphorylated SRM directly interacts with the surface of the PH domain in an intramolecular manner, thereby decreasing the PI4P-binding activity of the PH domain. In light of these findings, we propose that the hyperphosphorylation of SRM may trigger the dissociation of CERT from the Golgi apparatus, resulting in a functionally less active conformation of CERT.
Collapse
Affiliation(s)
- Toshihiko Sugiki
- From the Graduate School of Pharmaceutical Sciences, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.,the Japan Biological Informatics Consortium (JBiC), Aomi, Koto-ku, Tokyo 135-8073, Japan.,the Biomedicinal Information Research Center (BIRC), National Institute of Advanced Industrial Science and Technology (AIST), Aomi, Koto-ku, Tokyo 135-0064, Japan.,the Institute for Protein Research, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Daichi Egawa
- the Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Keigo Kumagai
- the Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Chojiro Kojima
- the Institute for Protein Research, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan.,the Graduate School and Faculty of Engineering, Yokohama National University, Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan, and
| | - Toshimichi Fujiwara
- the Institute for Protein Research, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Koh Takeuchi
- the Biomedicinal Information Research Center (BIRC), National Institute of Advanced Industrial Science and Technology (AIST), Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Ichio Shimada
- From the Graduate School of Pharmaceutical Sciences, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.,the Biomedicinal Information Research Center (BIRC), National Institute of Advanced Industrial Science and Technology (AIST), Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Kentaro Hanada
- the Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan,
| | - Hideo Takahashi
- the Biomedicinal Information Research Center (BIRC), National Institute of Advanced Industrial Science and Technology (AIST), Aomi, Koto-ku, Tokyo 135-0064, Japan, .,the Graduate School of Medical Life Science, Yokohama City University, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| |
Collapse
|
49
|
Liu X, Zhang N, Wang D, Zhu D, Yuan Q, Zhang X, Qian L, Niu H, Lu Y, Ren G, Tian K, Yuan H. Downregulation of reticulocalbin-1 differentially facilitates apoptosis and necroptosis in human prostate cancer cells. Cancer Sci 2018; 109:1147-1157. [PMID: 29453900 PMCID: PMC5891187 DOI: 10.1111/cas.13541] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 02/04/2018] [Accepted: 02/10/2018] [Indexed: 12/16/2022] Open
Abstract
Reticulocalbin 1 (RCN1), an endoplasmic reticulum (ER)‐resident Ca2+‐binding protein, is dysregulated in cancers, but its pathophysiological roles are largely unclear. Here, we demonstrate that RCN1 is overexpressed in clinical prostate cancer (PCa) samples, associated with cyclin B, not cyclin D1 expression, compared to that of benign tissues in a Chinese Han population. Downregulation of endogenous RCN1 significantly suppresses PCa cell viability and arrests the cell cycles of DU145 and LNCaP cells at the S and G2/M phases, respectively. RCN1 depletion causes ER stress, which is evidenced by induction of GRP78, activation of PERK and phosphorylation of eIF2α in PCa cells. Remarkably, RCN1 loss triggers DU145 cell apoptosis in a caspase‐dependent manner but mainly causes necroptosis in LNCaP cells. An animal‐based analysis confirms that RCN1 depletion suppresses cell proliferation and promotes cell death. Further investigations reveal that RCN1 depletion leads to elevation of phosphatase and tensin homolog (PTEN) and inactivation of AKT in DU145 cells. Silencing of PTEN partially restores apoptotic cells upon RCN1 loss. In LNCaP cells, predominant activation of CaMKII is important for necroptosis in response to RCN1 depletion. Thus, RCN1 may promote cell survival and serve as a useful target for cancer therapy.
Collapse
Affiliation(s)
- Xiaofei Liu
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Nianzhao Zhang
- Department of Urology, Qilu Hospital, Shandong University, Jinan, China
| | - Dawei Wang
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Deyu Zhu
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Quan Yuan
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Xiulei Zhang
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Lilin Qian
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Huanmin Niu
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Yi Lu
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Guijie Ren
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Keli Tian
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| | - Huiqing Yuan
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, China
| |
Collapse
|
50
|
Targeting PTEN in Colorectal Cancers. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1110:55-73. [DOI: 10.1007/978-3-030-02771-1_5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|