1
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Wang L, Chen Y, Li J, Westenbroek R, Philyaw T, Zheng N, Scott JD, Liu Q, Catterall WA. Anchored PKA synchronizes adrenergic phosphoregulation of cardiac Ca v1.2 channels. J Biol Chem 2024:107656. [PMID: 39128715 DOI: 10.1016/j.jbc.2024.107656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 07/10/2024] [Accepted: 07/31/2024] [Indexed: 08/13/2024] Open
Abstract
Adrenergic modulation of voltage gated Ca2+ currents is a context specific process. In the heart Cav1.2 channels initiate excitation-contraction coupling. This requires protein kinase A (PKA) phosphorylation of the small GTPase Rad (Ras associated with diabetes) and involves direct phosphorylation of a1 subunit of the Cav1.2 at Ser1700. A contributing factor is the proximity of PKA to the channel through association with A-kinase anchoring proteins (AKAPs). Disruption of PKA anchoring by the disruptor peptide AKAP-IS prevents up-regulation of Cav1.2 currents in tsA-201 cells. Biochemical analyses demonstrate that Rad does not function as an A-kinase anchoring protein. Electrophysiological recording shows that channel mutants lacking phosphorylation sites (Cav1.2 STAA) lose responsivity to the second messenger cAMP. Measurements in cardiomyocytes isolated from Rad-/- mice show that adrenergic activation of Cav1.2 is attenuated but not completely abolished. Whole animal electrocardiography studies reveal that cardiac selective Rad knockout mice exhibited higher baseline left-ventricular ejection fraction (EF), greater fractional shortening (FS), and increased heart rate as compared to control animals. Yet, each parameter of cardiac function was slightly elevated when Rad-/- mice were treated with the adrenergic agonist isoproterenol. Thus, phosphorylation of Cav1.2 and dissociation of phospho-Rad from the channel are local cAMP responsive events that act in concert to enhance L-type calcium currents. This convergence of local PKA regulatory events at the cardiac L-type calcium channel may permit maximal β-adrenergic influence on the fight-or-flight response.
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Affiliation(s)
- Lipeng Wang
- Departments of Pharmacology, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195
| | - Yi Chen
- Departments of Neurobiology and Biophysics, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195
| | - Jin Li
- Departments of Pharmacology, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195
| | - Ruth Westenbroek
- Departments of Pharmacology, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195
| | - Travis Philyaw
- Departments of Pharmacology, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195
| | - Ning Zheng
- Departments of Pharmacology, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195; Departments of Howard Hughes Medical Institute, University of Washington, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195
| | - John D Scott
- Departments of Pharmacology, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195.
| | - Qinghang Liu
- Departments of Neurobiology and Biophysics, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195.
| | - William A Catterall
- Departments of Pharmacology, School of Medicine, 1959 NE Pacific St., Seattle, WA 98195
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2
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Kharin A, Klussmann E. Many kinases for controlling the water channel aquaporin-2. J Physiol 2024; 602:3025-3039. [PMID: 37440212 DOI: 10.1113/jp284100] [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: 03/29/2023] [Accepted: 06/26/2023] [Indexed: 07/14/2023] Open
Abstract
Aquaporin-2 (AQP2) is a member of the aquaporin water channel family. In the kidney, AQP2 is expressed in collecting duct principal cells where it facilitates water reabsorption in response to antidiuretic hormone (arginine vasopressin, AVP). AVP induces the redistribution of AQP2 from intracellular vesicles and its incorporation into the plasma membrane. The plasma membrane insertion of AQP2 represents the crucial step in AVP-mediated water reabsorption. Dysregulation of the system preventing the AQP2 plasma membrane insertion causes diabetes insipidus (DI), a disease characterised by an impaired urine concentrating ability and polydipsia. There is no satisfactory treatment of DI available. This review discusses kinases that control the localisation of AQP2 and points out potential kinase-directed targets for the treatment of DI.
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Affiliation(s)
- Andrii Kharin
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Enno Klussmann
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
- DZHK (German Center for Cardiovascular Research), Berlin, Germany
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3
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Olivieri C, Wang Y, Walker C, Subrahmanian MV, Ha KN, Bernlohr D, Gao J, Camilloni C, Vendruscolo M, Taylor SS, Veglia G. The αC-β4 loop controls the allosteric cooperativity between nucleotide and substrate in the catalytic subunit of protein kinase A. eLife 2024; 12:RP91506. [PMID: 38913408 PMCID: PMC11196109 DOI: 10.7554/elife.91506] [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] [Indexed: 06/25/2024] Open
Abstract
Allosteric cooperativity between ATP and substrates is a prominent characteristic of the cAMP-dependent catalytic subunit of protein kinase A (PKA-C). This long-range synergistic action is involved in substrate recognition and fidelity, and it may also regulate PKA's association with regulatory subunits and other binding partners. To date, a complete understanding of this intramolecular mechanism is still lacking. Here, we integrated NMR(Nuclear Magnetic Resonance)-restrained molecular dynamics simulations and a Markov State Model to characterize the free energy landscape and conformational transitions of PKA-C. We found that the apoenzyme populates a broad free energy basin featuring a conformational ensemble of the active state of PKA-C (ground state) and other basins with lower populations (excited states). The first excited state corresponds to a previously characterized inactive state of PKA-C with the αC helix swinging outward. The second excited state displays a disrupted hydrophobic packing around the regulatory (R) spine, with a flipped configuration of the F100 and F102 residues at the αC-β4 loop. We validated the second excited state by analyzing the F100A mutant of PKA-C, assessing its structural response to ATP and substrate binding. While PKA-CF100A preserves its catalytic efficiency with Kemptide, this mutation rearranges the αC-β4 loop conformation, interrupting the coupling of the two lobes and abolishing the allosteric binding cooperativity. The highly conserved αC-β4 loop emerges as a pivotal element to control the synergistic binding of nucleotide and substrate, explaining how mutations or insertions near or within this motif affect the function and drug sensitivity in homologous kinases.
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Affiliation(s)
- Cristina Olivieri
- Department of Biochemistry, Molecular Biology, and Biophysics, University of MinnesotaMinneapolisUnited States
| | - Yingjie Wang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of MinnesotaMinneapolisUnited States
- Department of Chemistry and Supercomputing Institute, University of MinnesotaMinneapolisUnited States
| | - Caitlin Walker
- Department of Biochemistry, Molecular Biology, and Biophysics, University of MinnesotaMinneapolisUnited States
| | | | - Kim N Ha
- Department of Chemistry and Biochemistry, St. Catherine UniversityMinneapolisUnited States
| | - David Bernlohr
- Department of Biochemistry, Molecular Biology, and Biophysics, University of MinnesotaMinneapolisUnited States
| | - Jiali Gao
- Department of Chemistry and Supercomputing Institute, University of MinnesotaMinneapolisUnited States
| | - Carlo Camilloni
- Department of Chemistry, University of CambridgeCambridgeUnited Kingdom
| | | | - Susan S Taylor
- Department of Pharmacology, University of California at San DiegoSan DiegoUnited States
- Department of Chemistry and Biochemistry, University of California at San DiegoSan DiegoUnited States
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of MinnesotaMinneapolisUnited States
- Department of Chemistry and Supercomputing Institute, University of MinnesotaMinneapolisUnited States
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4
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Li Y, Huang M, Wang M, Wang Y, Deng P, Li C, Huang J, Chen H, Wei Z, Ouyang Q, Zhao J, Lu Y, Su S. Tumor cells impair immunological synapse formation via central nervous system-enriched metabolite. Cancer Cell 2024; 42:985-1002.e18. [PMID: 38821061 DOI: 10.1016/j.ccell.2024.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 02/22/2024] [Accepted: 05/06/2024] [Indexed: 06/02/2024]
Abstract
Tumors employ various strategies to evade immune surveillance. Central nervous system (CNS) has multiple features to restrain immune response. Whether tumors and CNS share similar programs of immunosuppression is elusive. Here, we analyze multi-omics data of tumors from HER2+ breast cancer patients receiving trastuzumab and anti-PD-L1 antibody and find that CNS-enriched N-acetyltransferase 8-like (NAT8L) and its metabolite N-acetylaspartate (NAA) are overexpressed in resistant tumors. In CNS, NAA is released during brain inflammation. NAT8L attenuates brain inflammation and impairs anti-tumor immunity by inhibiting cytotoxicity of natural killer (NK) cells and CD8+ T cells via NAA. NAA disrupts the formation of immunological synapse by promoting PCAF-induced acetylation of lamin A-K542, which inhibits the integration between lamin A and SUN2 and impairs polarization of lytic granules. We uncover that tumor cells mimic the anti-inflammatory mechanism of CNS to evade anti-tumor immunity and NAT8L is a potential target to enhance efficacy of anti-cancer agents.
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Affiliation(s)
- Yihong Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Min Huang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Minger Wang
- School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Yi Wang
- School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Peng Deng
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Chunni Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Jingying Huang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Hui Chen
- Guangdong Provincial Key Laboratory of Liver Disease Research the Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510630, China
| | - Zhihao Wei
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Qian Ouyang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Jinghua Zhao
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Yiwen Lu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Shicheng Su
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China; Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China; Department of Immunology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China; Biotherapy Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
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5
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Stahl A, Tomchik SM. Modeling neurodegenerative and neurodevelopmental disorders in the Drosophila mushroom body. Learn Mem 2024; 31:a053816. [PMID: 38876485 PMCID: PMC11199955 DOI: 10.1101/lm.053816.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 05/01/2024] [Indexed: 06/16/2024]
Abstract
The common fruit fly Drosophila melanogaster provides a powerful platform to investigate the genetic, molecular, cellular, and neural circuit mechanisms of behavior. Research in this model system has shed light on multiple aspects of brain physiology and behavior, from fundamental neuronal function to complex behaviors. A major anatomical region that modulates complex behaviors is the mushroom body (MB). The MB integrates multimodal sensory information and is involved in behaviors ranging from sensory processing/responses to learning and memory. Many genes that underlie brain disorders are conserved, from flies to humans, and studies in Drosophila have contributed significantly to our understanding of the mechanisms of brain disorders. Genetic mutations that mimic human diseases-such as Fragile X syndrome, neurofibromatosis type 1, Parkinson's disease, and Alzheimer's disease-affect MB structure and function, altering behavior. Studies dissecting the effects of disease-causing mutations in the MB have identified key pathological mechanisms, and the development of a complete connectome promises to add a comprehensive anatomical framework for disease modeling. Here, we review Drosophila models of human neurodevelopmental and neurodegenerative disorders via the effects of their underlying mutations on MB structure, function, and the resulting behavioral alterations.
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Affiliation(s)
- Aaron Stahl
- Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa 52242, USA
| | - Seth M Tomchik
- Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa 52242, USA
- Stead Family Department of Pediatrics, University of Iowa, Iowa City, Iowa 52242, USA
- Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa 52242, USA
- Hawk-IDDRC, University of Iowa, Iowa City, Iowa 52242, USA
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6
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Kang M, Senatore AJ, Naughton H, McTigue M, Beltman RJ, Herppich AA, Pflum MKH, Howe AK. Protein kinase A is a functional component of focal adhesions. J Biol Chem 2024; 300:107234. [PMID: 38552737 PMCID: PMC11044056 DOI: 10.1016/j.jbc.2024.107234] [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: 09/13/2023] [Revised: 03/06/2024] [Accepted: 03/17/2024] [Indexed: 04/09/2024] Open
Abstract
Focal adhesions (FAs) form the junction between extracellular matrix (ECM)-bound integrins and the actin cytoskeleton and also transmit signals that regulate cell adhesion, cytoskeletal dynamics, and cell migration. While many of these signals are rooted in reversible tyrosine phosphorylation, phosphorylation of FA proteins on Ser/Thr residues is far more abundant yet its mechanisms and consequences are far less understood. The cAMP-dependent protein kinase (protein kinase A; PKA) has important roles in cell adhesion and cell migration and is both an effector and regulator of integrin-mediated adhesion to the ECM. Importantly, subcellular localization plays a critically important role in specifying PKA function. Here, we show that PKA is present in isolated FA-cytoskeleton complexes and active within FAs in live cells. Furthermore, using kinase-catalyzed biotinylation of isolated FA-cytoskeleton complexes, we identify 53 high-stringency candidate PKA substrates within FAs. From this list, we validate tensin-3 (Tns3)-a well-established molecular scaffold, regulator of cell migration, and a component of focal and fibrillar adhesions-as a novel direct substrate for PKA. These observations identify a new pathway for phospho-regulation of Tns3 and, importantly, establish a new and important niche for localized PKA signaling and thus provide a foundation for further investigation of the role of PKA in the regulation of FA dynamics and signaling.
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Affiliation(s)
- Mingu Kang
- Department of Pharmacology, Larner College of Medicine, University of Vermont Cancer Center, Burlington, Vermont, USA; Department of Molecular Physiology & Biophysics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA
| | - Amanda J Senatore
- Department of Pharmacology, Larner College of Medicine, University of Vermont Cancer Center, Burlington, Vermont, USA; Department of Molecular Physiology & Biophysics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA
| | - Hannah Naughton
- Department of Pharmacology, Larner College of Medicine, University of Vermont Cancer Center, Burlington, Vermont, USA; Department of Molecular Physiology & Biophysics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA
| | - Madeline McTigue
- Department of Pharmacology, Larner College of Medicine, University of Vermont Cancer Center, Burlington, Vermont, USA; Department of Molecular Physiology & Biophysics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA
| | - Rachel J Beltman
- Department of Chemistry, Wayne State University, Detroit, Michigan, USA
| | - Andrew A Herppich
- Department of Chemistry, Wayne State University, Detroit, Michigan, USA
| | - Mary Kay H Pflum
- Department of Chemistry, Wayne State University, Detroit, Michigan, USA
| | - Alan K Howe
- Department of Pharmacology, Larner College of Medicine, University of Vermont Cancer Center, Burlington, Vermont, USA; Department of Molecular Physiology & Biophysics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA.
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7
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Musket A, Moorman JP, Zhang J, Jiang Y. PKIB, a Novel Target for Cancer Therapy. Int J Mol Sci 2024; 25:4664. [PMID: 38731883 PMCID: PMC11083500 DOI: 10.3390/ijms25094664] [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: 03/22/2024] [Revised: 04/18/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024] Open
Abstract
The serine-threonine kinase protein kinase A (PKA) is a cyclic AMP (cAMP)-dependent intracellular protein with multiple roles in cellular biology including metabolic and transcription regulation functions. The cAMP-dependent protein kinase inhibitor β (PKIB) is one of three known endogenous protein kinase inhibitors of PKA. The role of PKIB is not yet fully understood. Hormonal signaling is correlated with increased PKIB expression through genetic regulation, and increasing PKIB expression is associated with decreased cancer patient prognosis. Additionally, PKIB impacts cancer cell behavior through two mechanisms; the first is the nuclear modulation of transcriptional activation and the second is the regulation of oncogenic AKT signaling. The limited research into PKIB indicates the oncogenic potential of PKIB in various cancers. However, some studies suggest a role of PKIB in non-cancerous disease states. This review aims to summarize the current literature and background of PKIB regarding cancer and related issues. In particular, we will focus on cancer development and therapeutic possibilities, which are of paramount interest in PKIB oncology research.
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Affiliation(s)
- Anna Musket
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA; (A.M.); (J.P.M.)
- Center of Excellence in Inflammation, Infectious Disease and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Jonathan P. Moorman
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA; (A.M.); (J.P.M.)
- Center of Excellence in Inflammation, Infectious Disease and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
- Hepatitis (HCV/HBV/HIV) Program, James H. Quillen VA Medical Center, Department of Veterans Affairs, Johnson City, TN 37614, USA
| | - Jinyu Zhang
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA; (A.M.); (J.P.M.)
- Center of Excellence in Inflammation, Infectious Disease and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Yong Jiang
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA; (A.M.); (J.P.M.)
- Center of Excellence in Inflammation, Infectious Disease and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
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8
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Hardy JC, Pool EH, Bruystens JGH, Zhou X, Li Q, Zhou DR, Palay M, Tan G, Chen L, Choi JLC, Lee HN, Strack S, Wang D, Taylor SS, Mehta S, Zhang J. Molecular determinants and signaling effects of PKA RIα phase separation. Mol Cell 2024; 84:1570-1584.e7. [PMID: 38537638 PMCID: PMC11031308 DOI: 10.1016/j.molcel.2024.03.002] [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: 02/21/2023] [Revised: 12/07/2023] [Accepted: 03/01/2024] [Indexed: 04/09/2024]
Abstract
Spatiotemporal regulation of intracellular signaling molecules, such as the 3',5'-cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA), ensures proper cellular function. Liquid-liquid phase separation (LLPS) of the ubiquitous PKA regulatory subunit RIα promotes cAMP compartmentation and signaling specificity. However, the molecular determinants of RIα LLPS remain unclear. Here, we reveal that two separate dimerization interfaces, combined with the cAMP-induced unleashing of the PKA catalytic subunit (PKA-C) from the pseudosubstrate inhibitory sequence, drive RIα condensate formation in the cytosol of mammalian cells, which is antagonized by docking to A-kinase anchoring proteins. Strikingly, we find that the RIα pseudosubstrate region is critically involved in forming a non-canonical R:C complex, which recruits active PKA-C to RIα condensates to maintain low basal PKA activity in the cytosol. Our results suggest that RIα LLPS not only facilitates cAMP compartmentation but also spatially restrains active PKA-C, thus highlighting the functional versatility of biomolecular condensates in driving signaling specificity.
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Affiliation(s)
- Julia C Hardy
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA; Shu Chien-Gene Lay Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
| | - Emily H Pool
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jessica G H Bruystens
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Xin Zhou
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Qingrong Li
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Daojia R Zhou
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA; Shu Chien-Gene Lay Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
| | - Max Palay
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA
| | - Gerald Tan
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lisa Chen
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jaclyn L C Choi
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ha Neul Lee
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Stefan Strack
- Department of Pharmacology, University of Iowa, Iowa City, IA 52242, USA
| | - Dong Wang
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA; Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Susan S Taylor
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA; Shu Chien-Gene Lay Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA; Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.
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9
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Huang Z, Zhou L, Duan J, Qin S, Jiang J, Chen H, Wang K, Liu R, Yuan M, Tang X, Nice EC, Wei Y, Zhang W, Huang C. Oxidative Stress Promotes Liver Cancer Metastasis via RNF25-Mediated E-Cadherin Protein Degradation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306929. [PMID: 38286671 PMCID: PMC10987140 DOI: 10.1002/advs.202306929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/25/2023] [Indexed: 01/31/2024]
Abstract
Loss of E-cadherin (ECAD) is required in tumor metastasis. Protein degradation of ECAD in response to oxidative stress is found in metastasis of hepatocellular carcinoma (HCC) and is independent of transcriptional repression as usually known. Mechanistically, protein kinase A (PKA) senses oxidative stress by redox modification in its β catalytic subunit (PRKACB) at Cys200 and Cys344. The activation of PKA kinase activity subsequently induces RNF25 phosphorylation at Ser450 to initiate RNF25-catalyzed degradation of ECAD. Functionally, RNF25 repression induces ECAD protein expression and inhibits HCC metastasis in vitro and in vivo. Altogether, these results indicate that RNF25 is a critical regulator of ECAD protein turnover, and PKA is a necessary redox sensor to enable this process. This study provides some mechanistic insight into how oxidative stress-induced ECAD degradation promotes tumor metastasis of HCC.
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Affiliation(s)
- Zhao Huang
- Department of BiotherapyCancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China
| | - Li Zhou
- Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education)Institute for Viral HepatitisDepartment of Infectious DiseasesThe Second Affiliated HospitalChongqing Medical UniversityChongqing400016China
| | - Jiufei Duan
- Department of BiotherapyCancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China
| | - Siyuan Qin
- Department of BiotherapyCancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China
| | - Jingwen Jiang
- West China School of Public Health and West China Fourth HospitalSichuan UniversityChengdu610041China
| | - Haining Chen
- Colorectal Cancer CenterDepartment of General SurgeryWest China HospitalSichuan UniversityChengdu610041China
| | - Kui Wang
- West China School of Basic Medical Sciences & Forensic MedicineState Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China
| | - Rui Liu
- State Key Laboratory of Oral DiseasesNational Clinical Research Center for Oral DiseasesResearch Unit of Oral Carcinogenesis and ManagementChinese Academy of Medical SciencesWest China Hospital of StomatologySichuan UniversityChengdu610041China
| | - Minlan Yuan
- Mental Health Center and Psychiatric LaboratoryThe State Key Laboratory of BiotherapyWest China Biomedical Big Data CenterWest China Hospital of Sichuan UniversityChengdu610041China
| | - Xiangdong Tang
- Sleep Medicine CenterDepartment of Respiratory and Critical Care MedicineMental Health CenterTranslational Neuroscience CenterState Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China
| | - Edouard C. Nice
- Department of Biochemistry and Molecular BiologyMonash UniversityClaytonVIC3167Australia
| | - Yuquan Wei
- Department of BiotherapyCancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China
| | - Wei Zhang
- Frontiers Medical CenterTianfu Jincheng LaboratoryChengdu610212China
- Medical Big Data CenterSichuan UniversityChengdu610041China
| | - Canhua Huang
- Department of BiotherapyCancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China
- Frontiers Medical CenterTianfu Jincheng LaboratoryChengdu610212China
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10
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Hoppe N, Harrison S, Hwang SH, Chen Z, Karelina M, Deshpande I, Suomivuori CM, Palicharla VR, Berry SP, Tschaikner P, Regele D, Covey DF, Stefan E, Marks DS, Reiter JF, Dror RO, Evers AS, Mukhopadhyay S, Manglik A. GPR161 structure uncovers the redundant role of sterol-regulated ciliary cAMP signaling in the Hedgehog pathway. Nat Struct Mol Biol 2024; 31:667-677. [PMID: 38326651 PMCID: PMC11221913 DOI: 10.1038/s41594-024-01223-8] [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: 05/10/2023] [Accepted: 01/08/2024] [Indexed: 02/09/2024]
Abstract
The orphan G protein-coupled receptor (GPCR) GPR161 plays a central role in development by suppressing Hedgehog signaling. The fundamental basis of how GPR161 is activated remains unclear. Here, we determined a cryogenic-electron microscopy structure of active human GPR161 bound to heterotrimeric Gs. This structure revealed an extracellular loop 2 that occupies the canonical GPCR orthosteric ligand pocket. Furthermore, a sterol that binds adjacent to transmembrane helices 6 and 7 stabilizes a GPR161 conformation required for Gs coupling. Mutations that prevent sterol binding to GPR161 suppress Gs-mediated signaling. These mutants retain the ability to suppress GLI2 transcription factor accumulation in primary cilia, a key function of ciliary GPR161. By contrast, a protein kinase A-binding site in the GPR161 C terminus is critical in suppressing GLI2 ciliary accumulation. Our work highlights how structural features of GPR161 interface with the Hedgehog pathway and sets a foundation to understand the role of GPR161 function in other signaling pathways.
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Affiliation(s)
- Nicholas Hoppe
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Biophysics Graduate Program, University of California, San Francisco, CA, USA
| | - Simone Harrison
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Biophysics Graduate Program, University of California, San Francisco, CA, USA
| | - Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ziwei Chen
- Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA
- Taylor Institute for Innovative Psychiatric Research, St Louis, MO, USA
| | - Masha Karelina
- Biophysics Program, Stanford University, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | - Ishan Deshpande
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Carl-Mikael Suomivuori
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | - Vivek R Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Samuel P Berry
- Department of Systems Biology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Philipp Tschaikner
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
- Tyrolean Cancer Research Institute (TKFI), Innsbruck, Austria
| | - Dominik Regele
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Douglas F Covey
- Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA
- Taylor Institute for Innovative Psychiatric Research, St Louis, MO, USA
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO, USA
| | - Eduard Stefan
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
- Tyrolean Cancer Research Institute (TKFI), Innsbruck, Austria
| | - Debora S Marks
- Department of Systems Biology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Jeremy F Reiter
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Ron O Dror
- Biophysics Program, Stanford University, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | - Alex S Evers
- Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA
- Taylor Institute for Innovative Psychiatric Research, St Louis, MO, USA
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO, USA
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Aashish Manglik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA, USA.
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11
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Bock A, Irannejad R, Scott JD. cAMP signaling: a remarkably regional affair. Trends Biochem Sci 2024; 49:305-317. [PMID: 38310024 PMCID: PMC11175624 DOI: 10.1016/j.tibs.2024.01.004] [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: 11/02/2023] [Revised: 12/22/2023] [Accepted: 01/10/2024] [Indexed: 02/05/2024]
Abstract
Louis Pasteur once famously said 'in the fields of observation chance favors only the prepared mind'. Much of chance is being in the right place at the right time. This is particularly true in the crowded molecular environment of the cell where being in the right place is often more important than timing. Although Brownian motion argues that enzymes will eventually bump into substrates, this probability is greatly enhanced if both molecules reside in the same subcellular compartment. However, activation of cell signaling enzymes often requires the transmission of chemical signals from extracellular stimuli to intracellular sites of action. This review highlights new developments in our understanding of cAMP generation and the 3D utilization of this second messenger inside cells.
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Affiliation(s)
- Andreas Bock
- Rudolf Boehm Institute of Pharmacology and Toxicology, Medical Faculty, Leipzig University, 04107 Leipzig, Germany.
| | - Roshanak Irannejad
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
| | - John D Scott
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA.
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12
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Kang M, Otani Y, Guo Y, Yan J, Goult BT, Howe AK. The focal adhesion protein talin is a mechanically gated A-kinase anchoring protein. Proc Natl Acad Sci U S A 2024; 121:e2314947121. [PMID: 38513099 PMCID: PMC10990152 DOI: 10.1073/pnas.2314947121] [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: 08/29/2023] [Accepted: 02/22/2024] [Indexed: 03/23/2024] Open
Abstract
Protein kinase A (PKA) is a ubiquitous, promiscuous kinase whose activity is specified through subcellular localization mediated by A-kinase anchoring proteins (AKAPs). PKA has complex roles as both an effector and a regulator of integrin-mediated cell adhesion to extracellular matrix (ECM). Recent observations demonstrate that PKA is an active component of focal adhesions (FA), suggesting the existence of one or more FA AKAPs. Using a promiscuous biotin ligase fused to PKA type-IIα regulatory (RIIα) subunits and subcellular fractionation, we identify the archetypal FA protein talin1 as an AKAP. Talin is a large, mechanosensitive scaffold that directly links integrins to actin filaments and promotes FA assembly by recruiting additional components in a force-dependent manner. The rod region of talin1 consists of 62 α-helices bundled into 13 rod domains, R1 to R13. Direct binding assays and NMR spectroscopy identify helix41 in the R9 subdomain of talin as the PKA binding site. PKA binding to helix41 requires unfolding of the R9 domain, which requires the linker region between R9 and R10. Experiments with single molecules and in cells manipulated to alter actomyosin contractility demonstrate that the PKA-talin interaction is regulated by mechanical force across the talin molecule. Finally, talin mutations that disrupt PKA binding also decrease levels of total and phosphorylated PKA RII subunits as well as phosphorylation of VASP, a known PKA substrate, within FA. These observations identify a mechanically gated anchoring protein for PKA, a force-dependent binding partner for talin1, and a potential pathway for adhesion-associated mechanotransduction.
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Affiliation(s)
- Mingu Kang
- Department of Pharmacology, University of Vermont Larner College of Medicine, Burlington, VT05405
- Department of Molecular Physiology and Biophysics, University of Vermont Larner College of Medicine, Burlington, VT05405
- University of Vermont Cancer Center, Burlington, VT05405
| | - Yasumi Otani
- School of Biosciences, University of Kent, Canterbury, KentCT2 7NJ, United Kingdom
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, LiverpoolL69 7ZB, United Kingdom
| | - Yanyu Guo
- Department of Physics, Mechanobiology Institute, National University of Singapore, Singapore117542, Singapore
| | - Jie Yan
- Department of Physics, Mechanobiology Institute, National University of Singapore, Singapore117542, Singapore
| | - Benjamin T. Goult
- School of Biosciences, University of Kent, Canterbury, KentCT2 7NJ, United Kingdom
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, LiverpoolL69 7ZB, United Kingdom
| | - Alan K. Howe
- Department of Pharmacology, University of Vermont Larner College of Medicine, Burlington, VT05405
- Department of Molecular Physiology and Biophysics, University of Vermont Larner College of Medicine, Burlington, VT05405
- University of Vermont Cancer Center, Burlington, VT05405
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13
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Kang M, Senatore AJ, Naughton H, McTigue M, Beltman RJ, Herppich AA, Pflum MKH, Howe AK. Protein Kinase A is a Functional Component of Focal Adhesions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.08.18.553932. [PMID: 37645771 PMCID: PMC10462105 DOI: 10.1101/2023.08.18.553932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Focal adhesions (FAs) form the junction between extracellular matrix (ECM)-bound integrins and the actin cytoskeleton and also transmit signals that regulate cell adhesion, cytoskeletal dynamics, and cell migration. While many of these signals are rooted in reversible tyrosine phosphorylation, phosphorylation of FA proteins on Ser/Thr residues is far more abundant yet its mechanisms and consequences are far less understood. The cAMP-dependent protein kinase (protein kinase A; PKA) has important roles in cell adhesion and cell migration and is both an effector and regulator of integrin-mediated adhesion to the ECM. Importantly, subcellular localization plays a critically important role in specifying PKA function. Here, we show that PKA is present in isolated FA-cytoskeleton complexes and active within FAs in live cells. Furthermore, using kinase-catalyzed biotinylation of isolated FA-cytoskeleton complexes, we identify fifty-three high-stringency candidate PKA substrates within FAs. From this list, we validate tensin-3 (Tns3) - a well-established molecular scaffold, regulator of cell migration, and component of focal and fibrillar adhesions - as a novel direct substrate for PKA. These observations identify a new pathway for phospho-regulation of Tns3 and, importantly, establish a new and important niche for localized PKA signaling and thus provide a foundation for further investigation of the role of PKA in the regulation of FA dynamics and signaling.
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14
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Lauer SM, Omar MH, Golkowski MG, Kenerson HL, Lee KS, Pascual BC, Lim HC, Forbush K, Smith FD, Gordan JD, Ong SE, Yeung RS, Scott JD. Recruitment of BAG2 to DNAJ-PKAc scaffolds promotes cell survival and resistance to drug-induced apoptosis in fibrolamellar carcinoma. Cell Rep 2024; 43:113678. [PMID: 38236773 PMCID: PMC10964278 DOI: 10.1016/j.celrep.2024.113678] [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: 07/21/2023] [Revised: 11/23/2023] [Accepted: 01/02/2024] [Indexed: 01/30/2024] Open
Abstract
The DNAJ-PKAc fusion kinase is a defining feature of fibrolamellar carcinoma (FLC). FLC tumors are notoriously resistant to standard chemotherapies, with aberrant kinase activity assumed to be a contributing factor. By combining proximity proteomics, biochemical analyses, and live-cell photoactivation microscopy, we demonstrate that DNAJ-PKAc is not constrained by A-kinase anchoring proteins. Consequently, the fusion kinase phosphorylates a unique array of substrates, including proteins involved in translation and the anti-apoptotic factor Bcl-2-associated athanogene 2 (BAG2), a co-chaperone recruited to the fusion kinase through association with Hsp70. Tissue samples from patients with FLC exhibit increased levels of BAG2 in primary and metastatic tumors. Furthermore, drug studies implicate the DNAJ-PKAc/Hsp70/BAG2 axis in potentiating chemotherapeutic resistance. We find that the Bcl-2 inhibitor navitoclax enhances sensitivity to etoposide-induced apoptosis in cells expressing DNAJ-PKAc. Thus, our work indicates BAG2 as a marker for advanced FLC and a chemotherapeutic resistance factor in DNAJ-PKAc signaling scaffolds.
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Affiliation(s)
- Sophia M Lauer
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Mitchell H Omar
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Martin G Golkowski
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Heidi L Kenerson
- Department of Surgery, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Kyung-Soon Lee
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Bryan C Pascual
- Division of Hematology and Oncology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Huat C Lim
- Division of Hematology and Oncology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Katherine Forbush
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - F Donelson Smith
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - John D Gordan
- Division of Hematology and Oncology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Shao-En Ong
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Raymond S Yeung
- Department of Surgery, University of Washington Medical Center, Seattle, WA 98195, USA
| | - John D Scott
- Department of Pharmacology, University of Washington Medical Center, Seattle, WA 98195, USA.
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15
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Omar MH, Byrne DP, Shrestha S, Lakey TM, Lee KS, Lauer SM, Collins KB, Daly LA, Eyers CE, Baird GS, Ong SE, Kannan N, Eyers PA, Scott JD. Discovery of a Cushing's syndrome protein kinase A mutant that biases signaling through type I AKAPs. SCIENCE ADVANCES 2024; 10:eadl1258. [PMID: 38381834 PMCID: PMC10881042 DOI: 10.1126/sciadv.adl1258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 01/18/2024] [Indexed: 02/23/2024]
Abstract
Adrenal Cushing's syndrome is a disease of cortisol hypersecretion often caused by mutations in protein kinase A catalytic subunit (PKAc). Using a personalized medicine screening platform, we discovered a Cushing's driver mutation, PKAc-W196G, in ~20% of patient samples analyzed. Proximity proteomics and photokinetic imaging reveal that PKAcW196G is unexpectedly distinct from other described Cushing's variants, exhibiting retained association with type I regulatory subunits (RI) and their corresponding A kinase anchoring proteins (AKAPs). Molecular dynamics simulations predict that substitution of tryptophan-196 with glycine creates a 653-cubic angstrom cleft between the catalytic core of PKAcW196G and type II regulatory subunits (RII), but only a 395-cubic angstrom cleft with RI. Endocrine measurements show that overexpression of RIα or redistribution of PKAcW196G via AKAP recruitment counteracts stress hormone overproduction. We conclude that a W196G mutation in the kinase catalytic core skews R subunit selectivity and biases AKAP association to drive Cushing's syndrome.
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Affiliation(s)
- Mitchell H. Omar
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Dominic P. Byrne
- Department of Biochemistry, Cell and Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Safal Shrestha
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Tyler M. Lakey
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Kyung-Soon Lee
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Sophia M. Lauer
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Kerrie B. Collins
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Leonard A. Daly
- Centre for Proteome Research, Department of Biochemistry, Cell and Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Claire E. Eyers
- Centre for Proteome Research, Department of Biochemistry, Cell and Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Geoffrey S. Baird
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA
| | - Shao-En Ong
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Natarajan Kannan
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Patrick A. Eyers
- Department of Biochemistry, Cell and Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - John D. Scott
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
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16
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Willette BKA, Zhang JF, Zhang J, Tsvetanova NG. Endosome positioning coordinates spatially selective GPCR signaling. Nat Chem Biol 2024; 20:151-161. [PMID: 37500769 PMCID: PMC11024801 DOI: 10.1038/s41589-023-01390-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/29/2023] [Indexed: 07/29/2023]
Abstract
G-protein-coupled receptors (GPCRs) can initiate unique functional responses depending on the subcellular site of activation. Efforts to uncover the mechanistic basis of compartmentalized GPCR signaling have concentrated on the biochemical aspect of this regulation. Here we assess the biophysical positioning of receptor-containing endosomes as an alternative salient mechanism. We devise a strategy to rapidly and selectively redistribute receptor-containing endosomes 'on command' in intact cells without perturbing their biochemical composition. Next, we present two complementary optical readouts that enable robust measurements of bulk- and gene-specific GPCR/cyclic AMP (cAMP)-dependent transcriptional signaling with single-cell resolution. With these, we establish that disruption of native endosome positioning inhibits the initiation of the endosome-dependent transcriptional responses. Finally, we demonstrate a prominent mechanistic role of PDE-mediated cAMP hydrolysis and local protein kinase A activity in this process. Our study, therefore, illuminates a new mechanism regulating GPCR function by identifying endosome positioning as the principal mediator of spatially selective receptor signaling.
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Affiliation(s)
- Blair K A Willette
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA
| | - Jin-Fan Zhang
- Department of Pharmacology, University of California San Diego, La Jolla, CA, USA
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Jin Zhang
- Department of Pharmacology, University of California San Diego, La Jolla, CA, USA
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA
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17
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Lohse MJ, Bock A, Zaccolo M. G Protein-Coupled Receptor Signaling: New Insights Define Cellular Nanodomains. Annu Rev Pharmacol Toxicol 2024; 64:387-415. [PMID: 37683278 DOI: 10.1146/annurev-pharmtox-040623-115054] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
G protein-coupled receptors are the largest and pharmacologically most important receptor family and are involved in the regulation of most cell functions. Most of them reside exclusively at the cell surface, from where they signal via heterotrimeric G proteins to control the production of second messengers such as cAMP and IP3 as well as the activity of several ion channels. However, they may also internalize upon agonist stimulation or constitutively reside in various intracellular locations. Recent evidence indicates that their function differs depending on their precise cellular localization. This is because the signals they produce, notably cAMP and Ca2+, are mostly bound to cell proteins that significantly reduce their mobility, allowing the generation of steep concentration gradients. As a result, signals generated by the receptors remain confined to nanometer-sized domains. We propose that such nanometer-sized domains represent the basic signaling units in a cell and a new type of target for drug development.
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Affiliation(s)
- Martin J Lohse
- ISAR Bioscience Institute, Planegg/Munich, Germany;
- Rudolf Boehm Institute of Pharmacology and Toxicology, Leipzig University, Leipzig, Germany
| | - Andreas Bock
- Rudolf Boehm Institute of Pharmacology and Toxicology, Leipzig University, Leipzig, Germany
| | - Manuela Zaccolo
- Department of Physiology, Anatomy and Genetics and National Institute for Health and Care Research Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom;
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18
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Stengl M, Schneider AC. Contribution of membrane-associated oscillators to biological timing at different timescales. Front Physiol 2024; 14:1243455. [PMID: 38264332 PMCID: PMC10803594 DOI: 10.3389/fphys.2023.1243455] [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: 06/20/2023] [Accepted: 12/12/2023] [Indexed: 01/25/2024] Open
Abstract
Environmental rhythms such as the daily light-dark cycle selected for endogenous clocks. These clocks predict regular environmental changes and provide the basis for well-timed adaptive homeostasis in physiology and behavior of organisms. Endogenous clocks are oscillators that are based on positive feedforward and negative feedback loops. They generate stable rhythms even under constant conditions. Since even weak interactions between oscillators allow for autonomous synchronization, coupling/synchronization of oscillators provides the basis of self-organized physiological timing. Amongst the most thoroughly researched clocks are the endogenous circadian clock neurons in mammals and insects. They comprise nuclear clockworks of transcriptional/translational feedback loops (TTFL) that generate ∼24 h rhythms in clock gene expression entrained to the environmental day-night cycle. It is generally assumed that this TTFL clockwork drives all circadian oscillations within and between clock cells, being the basis of any circadian rhythm in physiology and behavior of organisms. Instead of the current gene-based hierarchical clock model we provide here a systems view of timing. We suggest that a coupled system of autonomous TTFL and posttranslational feedback loop (PTFL) oscillators/clocks that run at multiple timescales governs adaptive, dynamic homeostasis of physiology and behavior. We focus on mammalian and insect neurons as endogenous oscillators at multiple timescales. We suggest that neuronal plasma membrane-associated signalosomes constitute specific autonomous PTFL clocks that generate localized but interlinked oscillations of membrane potential and intracellular messengers with specific endogenous frequencies. In each clock neuron multiscale interactions of TTFL and PTFL oscillators/clocks form a temporally structured oscillatory network with a common complex frequency-band comprising superimposed multiscale oscillations. Coupling between oscillator/clock neurons provides the next level of complexity of an oscillatory network. This systemic dynamic network of molecular and cellular oscillators/clocks is suggested to form the basis of any physiological homeostasis that cycles through dynamic homeostatic setpoints with a characteristic frequency-band as hallmark. We propose that mechanisms of homeostatic plasticity maintain the stability of these dynamic setpoints, whereas Hebbian plasticity enables switching between setpoints via coupling factors, like biogenic amines and/or neuropeptides. They reprogram the network to a new common frequency, a new dynamic setpoint. Our novel hypothesis is up for experimental challenge.
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Affiliation(s)
- Monika Stengl
- Department of Biology, Animal Physiology/Neuroethology, University of Kassel, Kassel, Germany
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19
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Lin TY, Mai QN, Zhang H, Wilson E, Chien HC, Yee SW, Giacomini KM, Olgin JE, Irannejad R. Cardiac contraction and relaxation are regulated by distinct subcellular cAMP pools. Nat Chem Biol 2024; 20:62-73. [PMID: 37474759 PMCID: PMC10746541 DOI: 10.1038/s41589-023-01381-8] [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: 07/13/2022] [Accepted: 06/08/2023] [Indexed: 07/22/2023]
Abstract
Cells interpret a variety of signals through G-protein-coupled receptors (GPCRs) and stimulate the generation of second messengers such as cyclic adenosine monophosphate (cAMP). A long-standing puzzle is deciphering how GPCRs elicit different physiological responses despite generating similar levels of cAMP. We previously showed that some GPCRs generate cAMP from both the plasma membrane and the Golgi apparatus. Here we demonstrate that cardiomyocytes distinguish between subcellular cAMP inputs to elicit different physiological outputs. We show that generating cAMP from the Golgi leads to the regulation of a specific protein kinase A (PKA) target that increases the rate of cardiomyocyte relaxation. In contrast, cAMP generation from the plasma membrane activates a different PKA target that increases contractile force. We further validated the physiological consequences of these observations in intact zebrafish and mice. Thus, we demonstrate that the same GPCR acting through the same second messenger regulates cardiac contraction and relaxation dependent on its subcellular location.
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Affiliation(s)
- Ting-Yu Lin
- Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Quynh N Mai
- Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Hao Zhang
- Cardiovascular Research Institute, University of California, San Francisco, CA, USA
- Department of Medicine, Division of Cardiology, University of California San Francisco, San Francisco, CA, USA
| | - Emily Wilson
- Cardiovascular Research Institute, University of California, San Francisco, CA, USA
- Department of Medicine, Division of Cardiology, University of California San Francisco, San Francisco, CA, USA
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, California, CA, USA
| | - Sook Wah Yee
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, California, CA, USA
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, California, CA, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
| | - Jeffrey E Olgin
- Cardiovascular Research Institute, University of California, San Francisco, CA, USA
- Department of Medicine, Division of Cardiology, University of California San Francisco, San Francisco, CA, USA
| | - Roshanak Irannejad
- Cardiovascular Research Institute, University of California, San Francisco, CA, USA.
- Department of Biochemistry & Biophysics, University of California, San Francisco, CA, USA.
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20
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Hardy JC, Pool EH, Bruystens JGH, Zhou X, Li Q, Zhou DR, Palay M, Tan G, Chen L, Choi JLC, Lee HN, Strack S, Wang D, Taylor SS, Mehta S, Zhang J. Molecular Determinants and Signaling Effects of PKA RIα Phase Separation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.10.570836. [PMID: 38168176 PMCID: PMC10760030 DOI: 10.1101/2023.12.10.570836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Spatiotemporal regulation of intracellular signaling molecules, such as the 3',5'-cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA), ensures the specific execution of various cellular functions. Liquid-liquid phase separation (LLPS) of the ubiquitously expressed PKA regulatory subunit RIα was recently identified as a major driver of cAMP compartmentation and signaling specificity. However, the molecular determinants of RIα LLPS remain unclear. Here, we reveal that two separate dimerization interfaces combined with the cAMP-induced release of the PKA catalytic subunit (PKA-C) from the pseudosubstrate inhibitory sequence are required to drive RIα condensate formation in cytosol, which is antagonized by docking to A-kinase anchoring proteins. Strikingly, we find that the RIα pseudosubstrate region is critically involved in the formation of a non-canonical R:C complex, which serves to maintain low basal PKA activity in the cytosol by enabling the recruitment of active PKA-C to RIα condensates. Our results suggest that RIα LLPS not only facilitates cAMP compartmentation but also spatially restrains active PKA-C, thus highlighting the functional versatility of biomolecular condensates in driving signaling specificity.
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21
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Xiong WH, Qin M, Zhong H. PKA regulation of neuronal function requires the dissociation of catalytic subunits from regulatory subunits. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.05.556437. [PMID: 37732264 PMCID: PMC10508765 DOI: 10.1101/2023.09.05.556437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Protein kinase A (PKA) plays essential roles in diverse cellular functions. However, the spatiotemporal dynamics of endogenous PKA upon activation remain debated. The classical model predicts that PKA catalytic subunits dissociate from regulatory subunits in the presence of cAMP, whereas a second model proposes that catalytic subunits remain associated with regulatory subunits following physiological activation. Here we report that different PKA subtypes, as defined by the regulatory subunit, exhibit distinct subcellular localization at rest in CA1 neurons of cultured hippocampal slices. Nevertheless, when all tested PKA subtypes are activated by norepinephrine, presumably via the β-adrenergic receptor, catalytic subunits translocate to dendritic spines but regulatory subunits remain unmoved. These differential spatial dynamics between the subunits indicate that at least a significant fraction of PKA dissociates. Furthermore, PKA-dependent regulation of synaptic plasticity and transmission can be supported only by wildtype, dissociable PKA, but not by inseparable PKA. These results indicate that endogenous PKA regulatory and catalytic subunits dissociate to achieve PKA function in neurons.
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Affiliation(s)
- Wei-Hong Xiong
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Maozhen Qin
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Haining Zhong
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
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22
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Olivieri C, Wang Y, Walker C, Subrahmanian MV, Ha KN, Bernlohr DA, Gao J, Camilloni C, Vendruscolo M, Taylor SS, Veglia G. The αC-β4 loop controls the allosteric cooperativity between nucleotide and substrate in the catalytic subunit of protein kinase A. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.12.557419. [PMID: 37745542 PMCID: PMC10515842 DOI: 10.1101/2023.09.12.557419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Allosteric cooperativity between ATP and substrates is a prominent characteristic of the cAMP-dependent catalytic (C) subunit of protein kinase A (PKA). Not only this long-range synergistic action is involved in substrate recognition and fidelity, but it is likely to regulate PKA association with regulatory subunits and other binding partners. To date, a complete understanding of the molecular determinants for this intramolecular mechanism is still lacking. Here, we used an integrated NMR-restrained molecular dynamics simulations and a Markov Model to characterize the free energy landscape and conformational transitions of the catalytic subunit of protein kinase A (PKA-C). We found that the apo-enzyme populates a broad free energy basin featuring a conformational ensemble of the active state of PKA-C (ground state) and other basins with lower populations (excited states). The first excited state corresponds to a previously characterized inactive state of PKA-C with the αC helix swinging outward. The second excited state displays a disrupted hydrophobic packing around the regulatory (R) spine, with a flipped configuration of the F100 and F102 residues at the tip of the αC-β4 loop. To experimentally validate the second excited state, we mutated F100 into alanine and used NMR spectroscopy to characterize the binding thermodynamics and structural response of ATP and a prototypical peptide substrate. While the activity of PKA-CF100A toward a prototypical peptide substrate is unaltered and the enzyme retains its affinity for ATP and substrate, this mutation rearranges the αC-β4 loop conformation interrupting the allosteric coupling between nucleotide and substrate. The highly conserved αC-β4 loop emerges as a pivotal element able to modulate the synergistic binding between nucleotide and substrate and may affect PKA signalosome. These results may explain how insertion mutations within this motif affect drug sensitivity in other homologous kinases.
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Affiliation(s)
- Cristina Olivieri
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, MN 55455, USA
| | - Yingjie Wang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, MN 55455, USA
- Department of Chemistry and Supercomputing Institute, University of Minnesota, MN 55455, USA
| | - Caitlin Walker
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, MN 55455, USA
| | - Manu V. Subrahmanian
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, MN 55455, USA
| | - Kim N. Ha
- Departmenf of Chemistry and Biochemistry, St. Catherine University, MN 55105, USA
| | - David A. Bernlohr
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, MN 55455, USA
| | - Jiali Gao
- Department of Chemistry and Supercomputing Institute, University of Minnesota, MN 55455, USA
| | - Carlo Camilloni
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | | | - Susan S. Taylor
- Department of Pharmacology, University of California at San Diego, CA 92093, USA
- Department of Chemistry and Biochemistry, University of California at San Diego, CA 92093, USA
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, MN 55455, USA
- Department of Chemistry and Supercomputing Institute, University of Minnesota, MN 55455, USA
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23
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Cao M, Day AM, Galler M, Latimer HR, Byrne DP, Foy TW, Dwyer E, Bennett E, Palmer J, Morgan BA, Eyers PA, Veal EA. A peroxiredoxin-P38 MAPK scaffold increases MAPK activity by MAP3K-independent mechanisms. Mol Cell 2023; 83:3140-3154.e7. [PMID: 37572670 DOI: 10.1016/j.molcel.2023.07.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 05/19/2023] [Accepted: 07/14/2023] [Indexed: 08/14/2023]
Abstract
Peroxiredoxins (Prdxs) utilize reversibly oxidized cysteine residues to reduce peroxides and promote H2O2 signal transduction, including H2O2-induced activation of P38 MAPK. Prdxs form H2O2-induced disulfide complexes with many proteins, including multiple kinases involved in P38 MAPK signaling. Here, we show that a genetically encoded fusion between a Prdx and P38 MAPK is sufficient to hyperactivate the kinase in yeast and human cells by a mechanism that does not require the H2O2-sensing cysteine of the Prdx. We demonstrate that a P38-Prdx fusion protein compensates for loss of the yeast scaffold protein Mcs4 and MAP3K activity, driving yeast into mitosis. Based on our findings, we propose that the H2O2-induced formation of Prdx-MAPK disulfide complexes provides an alternative scaffold and signaling platform for MAPKK-MAPK signaling. The demonstration that formation of a complex with a Prdx is sufficient to modify the activity of a kinase has broad implications for peroxide-based signal transduction in eukaryotes.
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Affiliation(s)
- Min Cao
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Alison M Day
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Martin Galler
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Heather R Latimer
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Dominic P Byrne
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Thomas W Foy
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Emilia Dwyer
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Elise Bennett
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Jeremy Palmer
- Newcastle University Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Brian A Morgan
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Patrick A Eyers
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Elizabeth A Veal
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
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24
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Zou X, Shanmugam SK, Kanner SA, Sampson KJ, Kass RS, Colecraft HM. Divergent regulation of KCNQ1/E1 by targeted recruitment of protein kinase A to distinct sites on the channel complex. eLife 2023; 12:e83466. [PMID: 37650513 PMCID: PMC10499372 DOI: 10.7554/elife.83466] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 08/30/2023] [Indexed: 09/01/2023] Open
Abstract
The slow delayed rectifier potassium current, IKs, conducted through pore-forming Q1 and auxiliary E1 ion channel complexes is important for human cardiac action potential repolarization. During exercise or fright, IKs is up-regulated by protein kinase A (PKA)-mediated Q1 phosphorylation to maintain heart rhythm and optimum cardiac performance. Sympathetic up-regulation of IKs requires recruitment of PKA holoenzyme (two regulatory - RI or RII - and two catalytic Cα subunits) to Q1 C-terminus by an A kinase anchoring protein (AKAP9). Mutations in Q1 or AKAP9 that abolish their functional interaction result in long QT syndrome type 1 and 11, respectively, which increases the risk of sudden cardiac death during exercise. Here, we investigated the utility of a targeted protein phosphorylation (TPP) approach to reconstitute PKA regulation of IKs in the absence of AKAP9. Targeted recruitment of endogenous Cα to E1-YFP using a GFP/YFP nanobody (nano) fused to RIIα enabled acute cAMP-mediated enhancement of IKs, reconstituting physiological regulation of the channel complex. By contrast, nano-mediated tethering of RIIα or Cα to Q1-YFP constitutively inhibited IKs by retaining the channel intracellularly in the endoplasmic reticulum and Golgi. Proteomic analysis revealed that distinct phosphorylation sites are modified by Cα targeted to Q1-YFP compared to free Cα. Thus, functional outcomes of synthetically recruited PKA on IKs regulation is critically dependent on the site of recruitment within the channel complex. The results reveal insights into divergent regulation of IKs by phosphorylation across different spatial and time scales, and suggest a TPP approach to develop new drugs to prevent exercise-induced sudden cardiac death.
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Affiliation(s)
- Xinle Zou
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
| | - Sri Karthika Shanmugam
- Department of Physiology and Cellular Biophysics, Columbia UniversityNew YorkUnited States
| | - Scott A Kanner
- Doctoral Program in Neurobiology and Behavior, Columbia UniversityNew YorkUnited States
| | - Kevin J Sampson
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
| | - Robert S Kass
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
| | - Henry M Colecraft
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
- Doctoral Program in Neurobiology and Behavior, Columbia UniversityNew YorkUnited States
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25
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Kang M, Otani Y, Guo Y, Yan J, Goult BT, Howe AK. The focal adhesion protein talin is a mechanically-gated A-kinase anchoring protein (AKAP). BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.20.554038. [PMID: 37645895 PMCID: PMC10462126 DOI: 10.1101/2023.08.20.554038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The cAMP-dependent protein kinase (Protein Kinase A; PKA) is a ubiquitous, promiscuous kinase whose activity is focused and specified through subcellular localization mediated by A-kinase anchoring proteins (AKAPs). PKA has complex roles as both an effector and a regulator of integrin-mediated cell adhesion to the extracellular matrix (ECM). Recent observations demonstrate that PKA is an active component of focal adhesions (FA), intracellular complexes coupling ECM-bound integrins to the actin cytoskeleton, suggesting the existence of one or more FA AKAPs. Using a combination of a promiscuous biotin ligase fused to PKA type-IIα regulatory (RIIα) subunits and subcellular fractionation, we identify the archetypal FA protein talin1 as an AKAP. Talin is a large, mechanosensitive scaffold that directly links integrins to actin filaments and promotes FA assembly by recruiting additional components in a force-dependent manner. The rod region of talin1 consists of 62 α-helices bundled into 13 rod domains, R1-R13. Direct binding assays and nuclear magnetic resonance spectroscopy identify helix41 in the R9 subdomain of talin as the PKA binding site. PKA binding to helix41 requires unfolding of the R9 domain, which requires the linker region between R9 and R10. Finally, single-molecule experiments with talin1 and PKA, and experiments in cells manipulated to alter actomyosin contractility demonstrate that the PKA-talin interaction is regulated by mechanical force across the talin molecule. These observations identify the first mechanically-gated anchoring protein for PKA, a new force-dependent binding partner for talin1, and thus a new mechanism for coupling cellular tension and signal transduction.
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Reinhardt R, Leonard TA. A critical evaluation of protein kinase regulation by activation loop autophosphorylation. eLife 2023; 12:e88210. [PMID: 37470698 PMCID: PMC10359097 DOI: 10.7554/elife.88210] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/07/2023] [Indexed: 07/21/2023] Open
Abstract
Phosphorylation of proteins is a ubiquitous mechanism of regulating their function, localization, or activity. Protein kinases, enzymes that use ATP to phosphorylate protein substrates are, therefore, powerful signal transducers in eukaryotic cells. The mechanism of phosphoryl-transfer is universally conserved among protein kinases, which necessitates the tight regulation of kinase activity for the orchestration of cellular processes with high spatial and temporal fidelity. In response to a stimulus, many kinases enhance their own activity by autophosphorylating a conserved amino acid in their activation loop, but precisely how this reaction is performed is controversial. Classically, kinases that autophosphorylate their activation loop are thought to perform the reaction in trans, mediated by transient dimerization of their kinase domains. However, motivated by the recently discovered regulation mechanism of activation loop cis-autophosphorylation by a kinase that is autoinhibited in trans, we here review the various mechanisms of autoregulation that have been proposed. We provide a framework for critically evaluating biochemical, kinetic, and structural evidence for protein kinase dimerization and autophosphorylation, and share some thoughts on the implications of these mechanisms within physiological signaling networks.
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Affiliation(s)
- Ronja Reinhardt
- Max Perutz Labs, Vienna Biocenter Campus (VBC)ViennaAustria
- Medical University of Vienna, Center for Medical BiochemistryViennaAustria
| | - Thomas A Leonard
- Max Perutz Labs, Vienna Biocenter Campus (VBC)ViennaAustria
- Medical University of Vienna, Center for Medical BiochemistryViennaAustria
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27
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Lauer SM, Omar MH, Golkowski MG, Kenerson HL, Pascual BC, Forbush K, Smith FD, Gordan J, Ong SE, Yeung RS, Scott JD. Recruitment of BAG2 to DNAJ-PKAc scaffolds promotes cell survival and resistance to drug-induced apoptosis in fibrolamellar carcinoma. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.28.546958. [PMID: 37425703 PMCID: PMC10327129 DOI: 10.1101/2023.06.28.546958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
The DNAJ-PKAc fusion kinase is a defining feature of the adolescent liver cancer fibrolamellar carcinoma (FLC). A single lesion on chromosome 19 generates this mutant kinase by creating a fused gene encoding the chaperonin binding domain of Hsp40 (DNAJ) in frame with the catalytic core of protein kinase A (PKAc). FLC tumors are notoriously resistant to standard chemotherapies. Aberrant kinase activity is assumed to be a contributing factor. Yet recruitment of binding partners, such as the chaperone Hsp70, implies that the scaffolding function of DNAJ- PKAc may also underlie pathogenesis. By combining proximity proteomics with biochemical analyses and photoactivation live-cell imaging we demonstrate that DNAJ-PKAc is not constrained by A-kinase anchoring proteins. Consequently, the fusion kinase phosphorylates a unique array of substrates. One validated DNAJ-PKAc target is the Bcl-2 associated athanogene 2 (BAG2), a co-chaperone recruited to the fusion kinase through association with Hsp70. Immunoblot and immunohistochemical analyses of FLC patient samples correlate increased levels of BAG2 with advanced disease and metastatic recurrences. BAG2 is linked to Bcl-2, an anti-apoptotic factor that delays cell death. Pharmacological approaches tested if the DNAJ- PKAc/Hsp70/BAG2 axis contributes to chemotherapeutic resistance in AML12 DNAJ-PKAc hepatocyte cell lines using the DNA damaging agent etoposide and the Bcl-2 inhibitor navitoclax. Wildtype AML12 cells were susceptible to each drug alone and in combination. In contrast, AML12 DNAJ-PKAc cells were moderately affected by etoposide, resistant to navitoclax, but markedly susceptible to the drug combination. These studies implicate BAG2 as a biomarker for advanced FLC and a chemotherapeutic resistance factor in DNAJ-PKAc signaling scaffolds.
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28
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Omar MH, Kihiu M, Byrne DP, Lee KS, Lakey TM, Butcher E, Eyers PA, Scott JD. Classification of Cushing's syndrome PKAc mutants based upon their ability to bind PKI. Biochem J 2023; 480:875-890. [PMID: 37306403 PMCID: PMC11136536 DOI: 10.1042/bcj20230183] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/02/2023] [Accepted: 06/12/2023] [Indexed: 06/13/2023]
Abstract
Cushing's syndrome is an endocrine disorder caused by excess production of the stress hormone cortisol. Precision medicine strategies have identified single allele mutations within the PRKACA gene that drive adrenal Cushing's syndrome. These mutations promote perturbations in the catalytic core of protein kinase A (PKAc) that impair autoinhibition by regulatory subunits and compartmentalization via recruitment into AKAP signaling islands. PKAcL205R is found in ∼45% of patients, whereas PKAcE31V, PKAcW196R, and L198insW and C199insV insertion mutants are less prevalent. Mass spectrometry, cellular, and biochemical data indicate that Cushing's PKAc variants fall into two categories: those that interact with the heat-stable protein kinase inhibitor PKI, and those that do not. In vitro activity measurements show that wild-type PKAc and W196R activities are strongly inhibited by PKI (IC50 < 1 nM). In contrast, PKAcL205R activity is not blocked by the inhibitor. Immunofluorescent analyses show that the PKI-binding variants wild-type PKAc, E31V, and W196R are excluded from the nucleus and protected against proteolytic processing. Thermal stability measurements reveal that upon co-incubation with PKI and metal-bound nucleotide, the W196R variant tolerates melting temperatures 10°C higher than PKAcL205. Structural modeling maps PKI-interfering mutations to a ∼20 Å diameter area at the active site of the catalytic domain that interfaces with the pseudosubstrate of PKI. Thus, Cushing's kinases are individually controlled, compartmentalized, and processed through their differential association with PKI.
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Affiliation(s)
- Mitchell H. Omar
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
| | - Maryanne Kihiu
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
| | - Dominic P. Byrne
- Department of Biochemistry, Cell and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
| | - Kyung-Soon Lee
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
| | - Tyler M. Lakey
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
| | - Erik Butcher
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
| | - Patrick A. Eyers
- Department of Biochemistry, Cell and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
| | - John D. Scott
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
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29
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Murabito A, Bhatt J, Ghigo A. It Takes Two to Tango! Protein-Protein Interactions behind cAMP-Mediated CFTR Regulation. Int J Mol Sci 2023; 24:10538. [PMID: 37445715 DOI: 10.3390/ijms241310538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/16/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Over the last fifteen years, with the approval of the first molecular treatments, a breakthrough era has begun for patients with cystic fibrosis (CF), the rare genetic disease caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). These molecules, known as CFTR modulators, have led to unprecedented improvements in the lung function and quality of life of most CF patients. However, the efficacy of these drugs is still suboptimal, and the clinical response is highly variable even among individuals bearing the same mutation. Furthermore, not all patients carrying rare CFTR mutations are eligible for CFTR modulator therapies, indicating the need for alternative and/or add-on therapeutic approaches. Because the second messenger 3',5'-cyclic adenosine monophosphate (cAMP) represents the primary trigger for CFTR activation and a major regulator of different steps of the life cycle of the channel, there is growing interest in devising ways to fine-tune the cAMP signaling pathway for therapeutic purposes. This review article summarizes current knowledge regarding the role of cAMP signalosomes, i.e., multiprotein complexes bringing together key enzymes of the cAMP pathway, in the regulation of CFTR function, and discusses how modulating this signaling cascade could be leveraged for therapeutic intervention in CF.
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Affiliation(s)
- Alessandra Murabito
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center "Guido Tarone", University of Torino, 10126 Torino, Italy
| | - Janki Bhatt
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center "Guido Tarone", University of Torino, 10126 Torino, Italy
- Kither Biotech S.r.l., 10126 Torino, Italy
| | - Alessandra Ghigo
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center "Guido Tarone", University of Torino, 10126 Torino, Italy
- Kither Biotech S.r.l., 10126 Torino, Italy
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30
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Hoppe N, Harrison S, Hwang SH, Chen Z, Karelina M, Deshpande I, Suomivuori CM, Palicharla VR, Berry SP, Tschaikner P, Regele D, Covey DF, Stefan E, Marks DS, Reiter J, Dror RO, Evers AS, Mukhopadhyay S, Manglik A. GPR161 structure uncovers the redundant role of sterol-regulated ciliary cAMP signaling in the Hedgehog pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.23.540554. [PMID: 37292845 PMCID: PMC10245861 DOI: 10.1101/2023.05.23.540554] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The orphan G protein-coupled receptor (GPCR) GPR161 is enriched in primary cilia, where it plays a central role in suppressing Hedgehog signaling1. GPR161 mutations lead to developmental defects and cancers2,3,4. The fundamental basis of how GPR161 is activated, including potential endogenous activators and pathway-relevant signal transducers, remains unclear. To elucidate GPR161 function, we determined a cryogenic-electron microscopy structure of active GPR161 bound to the heterotrimeric G protein complex Gs. This structure revealed an extracellular loop 2 that occupies the canonical GPCR orthosteric ligand pocket. Furthermore, we identify a sterol that binds to a conserved extrahelical site adjacent to transmembrane helices 6 and 7 and stabilizes a GPR161 conformation required for Gs coupling. Mutations that prevent sterol binding to GPR161 suppress cAMP pathway activation. Surprisingly, these mutants retain the ability to suppress GLI2 transcription factor accumulation in cilia, a key function of ciliary GPR161 in Hedgehog pathway suppression. By contrast, a protein kinase A-binding site in the GPR161 C-terminus is critical in suppressing GLI2 ciliary accumulation. Our work highlights how unique structural features of GPR161 interface with the Hedgehog pathway and sets a foundation to understand the broader role of GPR161 function in other signaling pathways.
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Affiliation(s)
- Nicholas Hoppe
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Biophysics Graduate Program, University of California, San Francisco, CA, USA
| | - Simone Harrison
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Biophysics Graduate Program, University of California, San Francisco, CA, USA
| | - Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ziwei Chen
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Taylor Institute for Innovative Psychiatric Research, St. Louis, MO 63110, USA
| | - Masha Karelina
- Biophysics Program, Stanford University, Stanford, CA 94305, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | - Ishan Deshpande
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Carl-Mikael Suomivuori
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | - Vivek R. Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Samuel P. Berry
- Department of Systems Biology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Philipp Tschaikner
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Innsbruck 6020, Austria
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck; Tyrolean Cancer Research Institute (TKFI), Innsbruck 6020, Austria
| | - Dominik Regele
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Innsbruck 6020, Austria
| | - Douglas F. Covey
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Taylor Institute for Innovative Psychiatric Research, St. Louis, MO 63110, USA
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Eduard Stefan
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Innsbruck 6020, Austria
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck; Tyrolean Cancer Research Institute (TKFI), Innsbruck 6020, Austria
| | - Debora S. Marks
- Department of Systems Biology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Jeremy Reiter
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California 94158
| | - Ron O. Dror
- Biophysics Program, Stanford University, Stanford, CA 94305, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | - Alex S. Evers
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Taylor Institute for Innovative Psychiatric Research, St. Louis, MO 63110, USA
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Aashish Manglik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
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Paolocci E, Zaccolo M. Compartmentalised cAMP signalling in the primary cilium. Front Physiol 2023; 14:1187134. [PMID: 37256063 PMCID: PMC10226274 DOI: 10.3389/fphys.2023.1187134] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/25/2023] [Indexed: 06/01/2023] Open
Abstract
cAMP is a universal second messenger that relies on precise spatio-temporal regulation to control varied, and often opposing, cellular functions. This is achieved via selective activation of effectors embedded in multiprotein complexes, or signalosomes, that reside at distinct subcellular locations. cAMP is also one of many pathways known to operate within the primary cilium. Dysfunction of ciliary signaling leads to a class of diseases known as ciliopathies. In Autosomal Dominant Polycystic Kidney Disease (ADPKD), a ciliopathy characterized by the formation of fluid-filled kidney cysts, upregulation of cAMP signaling is known to drive cystogenesis. For decades it has been debated whether the primary cilium is an independent cAMP sub-compartment, or whether it shares a diffusible pool of cAMP with the cell body. Recent studies now suggest it is a specific pool of cAMP generated in the cilium that propels cyst formation in ADPKD, supporting the notion that this antenna-like organelle is a compartment within which cAMP signaling occurs independently from cAMP signaling in the bulk cytosol. Here we present examples of cAMP function in the cilium which suggest this mysterious organelle is home to more than one cAMP signalosome. We review evidence that ciliary membrane localization of G-Protein Coupled Receptors (GPCRs) determines their downstream function and discuss how optogenetic tools have contributed to establish that cAMP generated in the primary cilium can drive cystogenesis.
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Collins KB, Scott JD. Phosphorylation, compartmentalization, and cardiac function. IUBMB Life 2023; 75:353-369. [PMID: 36177749 PMCID: PMC10049969 DOI: 10.1002/iub.2677] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/15/2022] [Indexed: 11/08/2022]
Abstract
Protein phosphorylation is a fundamental element of cell signaling. First discovered as a biochemical switch in glycogen metabolism, we now know that this posttranslational modification permeates all aspects of cellular behavior. In humans, over 540 protein kinases attach phosphate to acceptor amino acids, whereas around 160 phosphoprotein phosphatases remove phosphate to terminate signaling. Aberrant phosphorylation underlies disease, and kinase inhibitor drugs are increasingly used clinically as targeted therapies. Specificity in protein phosphorylation is achieved in part because kinases and phosphatases are spatially organized inside cells. A prototypic example is compartmentalization of the cyclic adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase A through association with A-kinase anchoring proteins. This configuration creates autonomous signaling islands where the anchored kinase is constrained in proximity to activators, effectors, and selected substates. This article primarily focuses on A kinase anchoring protein (AKAP) signaling in the heart with an emphasis on anchoring proteins that spatiotemporally coordinate excitation-contraction coupling and hypertrophic responses.
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Affiliation(s)
- Kerrie B. Collins
- Department of Pharmacology, University of Washington, School of Medicine, 1959 NE Pacific Ave, Seattle WA, 98195
| | - John D. Scott
- Department of Pharmacology, University of Washington, School of Medicine, 1959 NE Pacific Ave, Seattle WA, 98195
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Kovanich D, Low TY, Zaccolo M. Using the Proteomics Toolbox to Resolve Topology and Dynamics of Compartmentalized cAMP Signaling. Int J Mol Sci 2023; 24:4667. [PMID: 36902098 PMCID: PMC10003371 DOI: 10.3390/ijms24054667] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 03/04/2023] Open
Abstract
cAMP is a second messenger that regulates a myriad of cellular functions in response to multiple extracellular stimuli. New developments in the field have provided exciting insights into how cAMP utilizes compartmentalization to ensure specificity when the message conveyed to the cell by an extracellular stimulus is translated into the appropriate functional outcome. cAMP compartmentalization relies on the formation of local signaling domains where the subset of cAMP signaling effectors, regulators and targets involved in a specific cellular response cluster together. These domains are dynamic in nature and underpin the exacting spatiotemporal regulation of cAMP signaling. In this review, we focus on how the proteomics toolbox can be utilized to identify the molecular components of these domains and to define the dynamic cellular cAMP signaling landscape. From a therapeutic perspective, compiling data on compartmentalized cAMP signaling in physiological and pathological conditions will help define the signaling events underlying disease and may reveal domain-specific targets for the development of precision medicine interventions.
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Affiliation(s)
- Duangnapa Kovanich
- Center for Vaccine Development, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom 73170, Thailand
| | - Teck Yew Low
- UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia
| | - Manuela Zaccolo
- Department of Physiology, Anatomy and Genetics and Oxford NIHR Biomedical Research Centre, University of Oxford, Oxford OX1 3PT, UK
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Chan GKL, Maisel S, Hwang YC, Pascual BC, Wolber RRB, Vu P, Patra KC, Bouhaddou M, Kenerson HL, Lim HC, Long D, Yeung RS, Sethupathy P, Swaney DL, Krogan NJ, Turnham RE, Riehle KJ, Scott JD, Bardeesy N, Gordan JD. Oncogenic PKA signaling increases c-MYC protein expression through multiple targetable mechanisms. eLife 2023; 12:e69521. [PMID: 36692000 PMCID: PMC9925115 DOI: 10.7554/elife.69521] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 01/22/2023] [Indexed: 01/25/2023] Open
Abstract
Genetic alterations that activate protein kinase A (PKA) are found in many tumor types. Yet, their downstream oncogenic signaling mechanisms are poorly understood. We used global phosphoproteomics and kinase activity profiling to map conserved signaling outputs driven by a range of genetic changes that activate PKA in human cancer. Two signaling networks were identified downstream of PKA: RAS/MAPK components and an Aurora Kinase A (AURKA)/glycogen synthase kinase (GSK3) sub-network with activity toward MYC oncoproteins. Findings were validated in two PKA-dependent cancer models: a novel, patient-derived fibrolamellar carcinoma (FLC) line that expresses a DNAJ-PKAc fusion and a PKA-addicted melanoma model with a mutant type I PKA regulatory subunit. We identify PKA signals that can influence both de novo translation and stability of the proto-oncogene c-MYC. However, the primary mechanism of PKA effects on MYC in our cell models was translation and could be blocked with the eIF4A inhibitor zotatifin. This compound dramatically reduced c-MYC expression and inhibited FLC cell line growth in vitro. Thus, targeting PKA effects on translation is a potential treatment strategy for FLC and other PKA-driven cancers.
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Affiliation(s)
- Gary KL Chan
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
| | - Samantha Maisel
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
| | - Yeonjoo C Hwang
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
| | - Bryan C Pascual
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
| | - Rebecca RB Wolber
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
| | - Phuong Vu
- Department of Medicine, Harvard Medical SchoolBostonUnited States
- Massachusetts General Hospital Cancer CenterBostonUnited States
| | - Krushna C Patra
- Department of Medicine, Harvard Medical SchoolBostonUnited States
- Massachusetts General Hospital Cancer CenterBostonUnited States
| | - Mehdi Bouhaddou
- Department of Cellular and Molecular Pharmacology, University of California San FranciscoSan FranciscoUnited States
- J. David Gladstone InstituteSan FranciscoUnited States
| | - Heidi L Kenerson
- Department of Surgery and Northwest Liver Research Program, University of WashingtonSeattleUnited States
| | - Huat C Lim
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
| | - Donald Long
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell UniversityNew YorkUnited States
| | - Raymond S Yeung
- Department of Surgery and Northwest Liver Research Program, University of WashingtonSeattleUnited States
| | - Praveen Sethupathy
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell UniversityNew YorkUnited States
| | - Danielle L Swaney
- Department of Cellular and Molecular Pharmacology, University of California San FranciscoSan FranciscoUnited States
- J. David Gladstone InstituteSan FranciscoUnited States
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California San FranciscoSan FranciscoUnited States
| | - Rigney E Turnham
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
| | - Kimberly J Riehle
- Department of Surgery and Northwest Liver Research Program, University of WashingtonSeattleUnited States
| | - John D Scott
- Department of Pharmacology, University of Washington Medical CenterSeattleUnited States
| | - Nabeel Bardeesy
- Department of Medicine, Harvard Medical SchoolBostonUnited States
- Massachusetts General Hospital Cancer CenterBostonUnited States
| | - John D Gordan
- Division of Hematology/Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San FranciscoSan FranciscoUnited States
- Quantitative Biosciences Institute (QBI), University of California San FranciscoSan FranciscoUnited States
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35
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Montalto G, Ricciarelli R. Tau, tau kinases, and tauopathies: An updated overview. Biofactors 2023. [PMID: 36688478 DOI: 10.1002/biof.1930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 12/13/2022] [Indexed: 01/24/2023]
Abstract
Tau is a macrotubule-associated protein primarily involved in the stabilization of the cytoskeleton. Under normal conditions, phosphorylation reduces the affinity of tau for tubulin, allowing the protein to detach from microtubules and ensuring the system dynamics in neuronal cells. However, hyperphosphorylated tau aggregates into paired helical filaments, the main constituents of neurofibrillary tangles found in the brains of patients with Alzheimer's disease and other tauopathies. In this review, we provide an overview of the structure of tau and the pathophysiological roles of tau phosphorylation. We also evaluate the major protein kinases involved and discuss the progress made in the development of drug therapies aimed at inhibiting tau kinases.
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Affiliation(s)
- Giulia Montalto
- Department of Experimental Medicine, University of Genoa, Genoa, Italy
| | - Roberta Ricciarelli
- Department of Experimental Medicine, University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
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36
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ZNF185 prevents stress fiber formation through the inhibition of RhoA in endothelial cells. Commun Biol 2023; 6:29. [PMID: 36631535 PMCID: PMC9834212 DOI: 10.1038/s42003-023-04416-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 01/03/2023] [Indexed: 01/13/2023] Open
Abstract
Signaling through cAMP/protein kinase A (PKA) promotes endothelial barrier function to prevent plasma leakage induced by inflammatory mediators. The discovery of PKA substrates in endothelial cells increases our understanding of the molecular mechanisms involved in vessel maturation. In this study, we evaluate a cAMP inducer, forskolin, and a phospho-PKA substrate antibody to identify ZNF185 as a PKA substrate. ZNF185 interacts with PKA and colocalizes with F-actin in endothelial cells. Both ZNF185 and F-actin accumulate in the plasma membrane region in response to forskolin to stabilize the cortical actin structure. By contrast, ZNF185 knockdown disrupts actin filaments and promotes stress fiber formation without inflammatory mediators. Constitutive activation of RhoA is induced by ZNF185 knockdown, which results in forskolin-resistant endothelial barrier dysfunction. Knockout of mouse Zfp185 which is an orthologous gene of human ZNF185 increases vascular leakage in response to inflammatory stimuli in vivo. Thrombin protease is used as a positive control to assemble stress fibers via RhoA activation. Unexpectedly, ZNF185 is cleaved by thrombin, resulting in an N-terminal actin-targeting domain and a C-terminal PKA-interacting domain. Irreversible dysfunction of ZNF185 protein potentially causes RhoA-dependent stress fiber formation by thrombin.
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Diering GH. Remembering and forgetting in sleep: Selective synaptic plasticity during sleep driven by scaling factors Homer1a and Arc. Neurobiol Stress 2022; 22:100512. [PMID: 36632309 PMCID: PMC9826981 DOI: 10.1016/j.ynstr.2022.100512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 12/01/2022] [Accepted: 12/29/2022] [Indexed: 01/02/2023] Open
Abstract
Sleep is a conserved and essential process that supports learning and memory. Synapses are a major target of sleep function and a locus of sleep need. Evidence in the literature suggests that the need for sleep has a cellular or microcircuit level basis, and that sleep need can accumulate within localized brain regions as a function of waking activity. Activation of sleep promoting kinases and accumulation of synaptic phosphorylation was recently shown to be part of the molecular basis for the localized sleep need. A prominent hypothesis in the field suggests that some benefits of sleep are mediated by a broad but selective weakening, or scaling-down, of synaptic strength during sleep in order to offset increased excitability from synaptic potentiation during wake. The literature also shows that synapses can be strengthened during sleep, raising the question of what molecular mechanisms may allow for selection of synaptic plasticity types during sleep. Here I describe mechanisms of action of the scaling factors Arc and Homer1a in selective plasticity and links with sleep need. Arc and Homer1a are induced in neurons in response to waking neuronal activity and accumulate with time spent awake. I suggest that during sleep, Arc and Homer1a drive broad weakening of synapses through homeostatic scaling-down, but in a manner that is sensitive to the plasticity history of individual synapses, based on patterned phosphorylation of synaptic proteins. Therefore, Arc and Homer1a may offer insights into the intricate links between a cellular basis of sleep need and memory consolidation during sleep.
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Affiliation(s)
- Graham H. Diering
- Department of Cell Biology and Physiology and the UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,Carolina Institute for Developmental Disabilities, USA,111 Mason Farm Road, 5200 Medical and Biomolecular Research Building, Chapel Hill, NC, 27599-7545, USA.
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38
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Wang Q, Lu D, Liu H, Li C. Tetramerization of GH2 β-Glucuronidases is Essential for Catalyzing the Hydrolysis of the Large Substrate Glycyrrhizin. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:16286-16297. [PMID: 36516995 DOI: 10.1021/acs.jafc.2c06859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In this study, structural analysis was employed to identify three hotspot residues that contribute most to the tetramer formation of a glycoside hydrolase family 2 (GH2) β-glucuronidase (GUS) from Aspergillus oryzae Li-3. Single-point mutation at these sites completely disrupted the tetramer structure and abolished the glycyrrhizin (GL)-hydrolyzing activity. Then, the W522A dimer was refactored into a tetramer by disulfide bonding, and partial GL activity was restored. Further saturated mutation showed a strong correlation between the GL activity of the mutants and their tetramer ratios. Molecular simulations were employed to illustrate the critical role of the tetramer interface in maintaining a functional active-site structure. The three highly conserved tetramer-forming residues were finally applied to two other GH2 GUSs for tetramer dissociation and demonstrated the significance of the homotetramerization for GL-hydrolyzing activity of GH2 GUSs. This study lays foundation for engineering GL-hydrolyzing GUSs at the quaternary structure level for function regulations.
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Affiliation(s)
- Qibin Wang
- Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 10081, PR China
| | - Dingyuan Lu
- Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 10081, PR China
| | - Hu Liu
- Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 10081, PR China
| | - Chun Li
- Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 10081, PR China
- Key Laboratory for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 10084, PR China
- Center for Synthetic & Systems Biology, Tsinghua University, Beijing 10084, PR China
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Nuanced Interactions between AKAP79 and STIM1 with Orai1 Ca 2+ Channels at Endoplasmic Reticulum-Plasma Membrane Junctions Sustain NFAT Activation. Mol Cell Biol 2022; 42:e0017522. [PMID: 36317924 PMCID: PMC9670898 DOI: 10.1128/mcb.00175-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A-kinase anchoring protein 79 (AKAP79) is a human scaffolding protein that organizes Ca2+/calmodulin-dependent protein phosphatase calcineurin, calmodulin, cAMP-dependent protein kinase, protein kinase C, and the transcription factor nuclear factor of activated T cells (NFAT1) into a signalosome at the plasma membrane. Upon Ca2+ store depletion, AKAP79 interacts with the N-terminus of STIM1-gated Orai1 Ca2+ channels, enabling Ca2+ nanodomains to stimulate calcineurin. Calcineurin then dephosphorylates and activates NFAT1, which then translocates to the nucleus. A fundamental question is how signalosomes maintain long-term signaling when key effectors are released and therefore removed beyond the reach of the activating signal. Here, we show that the AKAP79-Orai1 interaction is considerably more transient than that of STIM1-Orai1. Free AKAP79, with calcineurin and NFAT1 in tow, is able to replace rapidly AKAP79 devoid of NFAT1 on Orai1, in the presence of continuous Ca2+ entry. We also show that Ca2+ nanodomains near Orai1 channels activate almost the entire cytosolic pool of NFAT1. Recycling of inactive NFAT1 from the cytoplasm to AKAP79 in the plasma membrane, coupled with the relatively weak interaction between AKAP79 and Orai1, maintain excitation-transcription coupling. By measuring rates for AKAP79-NFAT interaction, we formulate a mathematical model that simulates NFAT dynamics at the plasma membrane.
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40
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Xenias HS, Chen C, Kang S, Cherian S, Situ X, Shanmugasundaram B, Liu G, Scesa G, Chan CS, Parisiadou L. R1441C and G2019S LRRK2 knockin mice have distinct striatal molecular, physiological, and behavioral alterations. Commun Biol 2022; 5:1211. [PMID: 36357506 PMCID: PMC9649688 DOI: 10.1038/s42003-022-04136-8] [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: 07/27/2020] [Accepted: 10/20/2022] [Indexed: 11/12/2022] Open
Abstract
LRRK2 mutations are closely associated with Parkinson's disease (PD). Convergent evidence suggests that LRRK2 regulates striatal function. Here, by using knock-in mouse lines expressing the two most common LRRK2 pathogenic mutations-G2019S and R1441C-we investigated how LRRK2 mutations altered striatal physiology. While we found that both R1441C and G2019S mice displayed reduced nigrostriatal dopamine release, hypoexcitability in indirect-pathway striatal projection neurons, and alterations associated with an impaired striatal-dependent motor learning were observed only in the R1441C mice. We also showed that increased synaptic PKA activities in the R1441C and not G2019S mice underlie the specific alterations in motor learning deficits in the R1441C mice. In summary, our data argue that LRRK2 mutations' impact on the striatum cannot be simply generalized. Instead, alterations in electrochemical, electrophysiological, molecular, and behavioral levels were distinct between LRRK2 mutations. Our findings offer mechanistic insights for devising and optimizing treatment strategies for PD patients.
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Affiliation(s)
- Harry S Xenias
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Chuyu Chen
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Shuo Kang
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Suraj Cherian
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Xiaolei Situ
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Guoxiang Liu
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Giuseppe Scesa
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - C Savio Chan
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
| | - Loukia Parisiadou
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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41
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Kumar GA, Puthenveedu MA. Diversity and specificity in location-based signaling outputs of neuronal GPCRs. Curr Opin Neurobiol 2022; 76:102601. [DOI: 10.1016/j.conb.2022.102601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/27/2022] [Accepted: 06/01/2022] [Indexed: 11/30/2022]
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Happ JT, Arveseth CD, Bruystens J, Bertinetti D, Nelson IB, Olivieri C, Zhang J, Hedeen DS, Zhu JF, Capener JL, Bröckel JW, Vu L, King CC, Ruiz-Perez VL, Ge X, Veglia G, Herberg FW, Taylor SS, Myers BR. A PKA inhibitor motif within SMOOTHENED controls Hedgehog signal transduction. Nat Struct Mol Biol 2022; 29:990-999. [PMID: 36202993 PMCID: PMC9696579 DOI: 10.1038/s41594-022-00838-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/22/2022] [Indexed: 02/03/2023]
Abstract
The Hedgehog (Hh) cascade is central to development, tissue homeostasis and cancer. A pivotal step in Hh signal transduction is the activation of glioma-associated (GLI) transcription factors by the atypical G protein-coupled receptor (GPCR) SMOOTHENED (SMO). How SMO activates GLI remains unclear. Here we show that SMO uses a decoy substrate sequence to physically block the active site of the cAMP-dependent protein kinase (PKA) catalytic subunit (PKA-C) and extinguish its enzymatic activity. As a result, GLI is released from phosphorylation-induced inhibition. Using a combination of in vitro, cellular and organismal models, we demonstrate that interfering with SMO-PKA pseudosubstrate interactions prevents Hh signal transduction. The mechanism uncovered echoes one used by the Wnt cascade, revealing an unexpected similarity in how these two essential developmental and cancer pathways signal intracellularly. More broadly, our findings define a mode of GPCR-PKA communication that may be harnessed by a range of membrane receptors and kinases.
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Affiliation(s)
- John T Happ
- Department of Oncological Sciences, Department of Biochemistry, and Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Corvin D Arveseth
- Department of Oncological Sciences, Department of Biochemistry, and Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA
- Washington University School of Medicine, St. Louis, MO, USA
| | - Jessica Bruystens
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Daniela Bertinetti
- Institute for Biology, Department of Biochemistry, University of Kassel, Kassel, Germany
| | - Isaac B Nelson
- Department of Oncological Sciences, Department of Biochemistry, and Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Cristina Olivieri
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Jingyi Zhang
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, CA, USA
| | - Danielle S Hedeen
- Department of Oncological Sciences, Department of Biochemistry, and Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Ju-Fen Zhu
- Department of Oncological Sciences, Department of Biochemistry, and Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Jacob L Capener
- Department of Oncological Sciences, Department of Biochemistry, and Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA
- Biological and Biomedical Sciences Program, University of North Carolina, Chapel Hill, NC, USA
| | - Jan W Bröckel
- Institute for Biology, Department of Biochemistry, University of Kassel, Kassel, Germany
| | - Lily Vu
- Department of Neurobiology, University of California, San Diego, La Jolla, CA, USA
| | - C C King
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Victor L Ruiz-Perez
- Instituto de Investigaciones Biomédicas 'Alberto Sols,' Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid, Madrid, Spain
- CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Xuecai Ge
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, CA, USA
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Friedrich W Herberg
- Institute for Biology, Department of Biochemistry, University of Kassel, Kassel, Germany
| | - Susan S Taylor
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA.
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA.
| | - Benjamin R Myers
- Department of Oncological Sciences, Department of Biochemistry, and Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA.
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Drozdz MM, Doane AS, Alkallas R, Desman G, Bareja R, Reilly M, Bang J, Yusupova M, You J, Eraslan Z, Wang JZ, Verma A, Aguirre K, Kane E, Watson IR, Elemento O, Piskounova E, Merghoub T, Zippin JH. A nuclear cAMP microdomain suppresses tumor growth by Hippo pathway inactivation. Cell Rep 2022; 40:111412. [PMID: 36170819 PMCID: PMC9549417 DOI: 10.1016/j.celrep.2022.111412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 07/19/2022] [Accepted: 09/01/2022] [Indexed: 02/06/2023] Open
Abstract
Cyclic AMP (cAMP) signaling is localized to multiple spatially distinct microdomains, but the role of cAMP microdomains in cancer cell biology is poorly understood. Here, we present a tunable genetic system that allows us to activate cAMP signaling in specific microdomains. We uncover a nuclear cAMP microdomain that activates a tumor-suppressive pathway in a broad range of cancers by inhibiting YAP, a key effector protein of the Hippo pathway, inside the nucleus. We show that nuclear cAMP induces a LATS-dependent pathway leading to phosphorylation of nuclear YAP solely at serine 397 and export of YAP from the nucleus with no change in YAP protein stability. Thus, nuclear cAMP inhibition of nuclear YAP is distinct from other known mechanisms of Hippo regulation. Pharmacologic targeting of specific cAMP microdomains remains an untapped therapeutic approach for cancer; thus, drugs directed at the nuclear cAMP microdomain may provide avenues for the treatment of cancer.
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Affiliation(s)
- Marek M. Drozdz
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Ashley S. Doane
- Englander Institute for Precision Medicine, Joan and Sanford I. Weill Medical College of Cornell University, New York NY 10065, USA
| | - Rached Alkallas
- Rosalind and Morris Goodman Cancer Institute, Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada,Department of Human Genetics, McGill University, Montréal, QC H3A 0C7, Canada,McGill Genome Centre, McGill University, Montreal, QC H3A 0G1, Canada
| | - Garrett Desman
- Department of Pathology and Laboratory Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Rohan Bareja
- Englander Institute for Precision Medicine, Joan and Sanford I. Weill Medical College of Cornell University, New York NY 10065, USA,Institute for Computational Biomedicine, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Michael Reilly
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Jakyung Bang
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Maftuna Yusupova
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Jaewon You
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Zuhal Eraslan
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Jenny Z. Wang
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Akanksha Verma
- Englander Institute for Precision Medicine, Joan and Sanford I. Weill Medical College of Cornell University, New York NY 10065, USA
| | - Kelsey Aguirre
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Elsbeth Kane
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Ian R. Watson
- Rosalind and Morris Goodman Cancer Institute, Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Olivier Elemento
- Englander Institute for Precision Medicine, Joan and Sanford I. Weill Medical College of Cornell University, New York NY 10065, USA,Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10029, USA
| | - Elena Piskounova
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA,Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10029, USA,Senior author
| | - Taha Merghoub
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA,Swim Across America and Ludwig Collaborative Laboratory, Immunology Program, Parker Institute for Cancer Immunotherapy at Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA,Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10029, USA,Department of Pharmacology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA,Senior author
| | - Jonathan H. Zippin
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA,Englander Institute for Precision Medicine, Joan and Sanford I. Weill Medical College of Cornell University, New York NY 10065, USA,Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10029, USA,Department of Pharmacology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA,Senior author,Lead contact,Correspondence:
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44
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Guarina L, Moghbel AN, Pourhosseinzadeh MS, Cudmore RH, Sato D, Clancy CE, Santana LF. Biological noise is a key determinant of the reproducibility and adaptability of cardiac pacemaking and EC coupling. J Gen Physiol 2022; 154:213185. [PMID: 35482009 PMCID: PMC9059386 DOI: 10.1085/jgp.202012613] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 03/16/2022] [Accepted: 04/07/2022] [Indexed: 12/23/2022] Open
Abstract
Each heartbeat begins with the generation of an action potential in pacemaking cells in the sinoatrial node. This signal triggers contraction of cardiac muscle through a process termed excitation-contraction (EC) coupling. EC coupling is initiated in dyadic structures of cardiac myocytes, where ryanodine receptors in the junctional sarcoplasmic reticulum come into close apposition with clusters of CaV1.2 channels in invaginations of the sarcolemma. Cooperative activation of CaV1.2 channels within these clusters causes a local increase in intracellular Ca2+ that activates the juxtaposed ryanodine receptors. A salient feature of healthy cardiac function is the reliable and precise beat-to-beat pacemaking and amplitude of Ca2+ transients during EC coupling. In this review, we discuss recent discoveries suggesting that the exquisite reproducibility of this system emerges, paradoxically, from high variability at subcellular, cellular, and network levels. This variability is attributable to stochastic fluctuations in ion channel trafficking, clustering, and gating, as well as dyadic structure, which increase intracellular Ca2+ variance during EC coupling. Although the effects of these large, local fluctuations in function and organization are sometimes negligible at the macroscopic level owing to spatial-temporal summation within and across cells in the tissue, recent work suggests that the "noisiness" of these intracellular Ca2+ events may either enhance or counterintuitively reduce variability in a context-dependent manner. Indeed, these noisy events may represent distinct regulatory features in the tuning of cardiac contractility. Collectively, these observations support the importance of incorporating experimentally determined values of Ca2+ variance in all EC coupling models. The high reproducibility of cardiac contraction is a paradoxical outcome of high Ca2+ signaling variability at subcellular, cellular, and network levels caused by stochastic fluctuations in multiple processes in time and space. This underlying stochasticity, which counterintuitively manifests as reliable, consistent Ca2+ transients during EC coupling, also allows for rapid changes in cardiac rhythmicity and contractility in health and disease.
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Affiliation(s)
- Laura Guarina
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | - Ariana Neelufar Moghbel
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | | | - Robert H Cudmore
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | - Daisuke Sato
- Department of Pharmacology, University of California Davis School of Medicine, Davis, CA
| | - Colleen E Clancy
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | - Luis Fernando Santana
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
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45
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Abstract
Protein kinase A (PKA) directly phosphorylates aquaporin-2 (AQP2) water channels in renal collecting ducts to reabsorb water from urine for the maintenance of systemic water homeostasis. More than 50 functionally distinct PKA-anchoring proteins (AKAPs) respectively create compartmentalized PKA signaling to determine the substrate specificity of PKA. Identification of an AKAP responsible for AQP2 phosphorylation is an essential step toward elucidating the molecular mechanisms of urinary concentration. PKA activation by several compounds is a novel screening strategy to uncover PKA substrates whose phosphorylation levels were nearly perfectly correlated with that of AQP2. The leading candidate in this assay proved to be an AKAP termed lipopolysaccharide-responsive and beige-like anchor protein (LRBA). We found that LRBA colocalized with AQP2 in vivo, and Lrba knockout mice displayed a polyuric phenotype with severely impaired AQP2 phosphorylation. Most of the PKA substrates other than AQP2 were adequately phosphorylated by PKA in the absence of LRBA, demonstrating that LRBA-anchored PKA preferentially phosphorylated AQP2 in renal collecting ducts. Furthermore, the LRBA-PKA interaction, rather than other AKAP-PKA interactions, was robustly dissociated by PKA activation. AKAP-PKA interaction inhibitors have attracted attention for their ability to directly phosphorylate AQP2. Therefore, the LRBA-PKA interaction is a promising drug target for the development of anti-aquaretics.
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46
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Svec KV, Howe AK. Protein Kinase A in cellular migration—Niche signaling of a ubiquitous kinase. Front Mol Biosci 2022; 9:953093. [PMID: 35959460 PMCID: PMC9361040 DOI: 10.3389/fmolb.2022.953093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/30/2022] [Indexed: 12/28/2022] Open
Abstract
Cell migration requires establishment and maintenance of directional polarity, which in turn requires spatial heterogeneity in the regulation of protrusion, retraction, and adhesion. Thus, the signaling proteins that regulate these various structural processes must also be distinctly regulated in subcellular space. Protein Kinase A (PKA) is a ubiquitous serine/threonine kinase involved in innumerable cellular processes. In the context of cell migration, it has a paradoxical role in that global inhibition or activation of PKA inhibits migration. It follows, then, that the subcellular regulation of PKA is key to bringing its proper permissive and restrictive functions to the correct parts of the cell. Proper subcellular regulation of PKA controls not only when and where it is active but also specifies the targets for that activity, allowing the cell to use a single, promiscuous kinase to exert distinct functions within different subcellular niches to facilitate cell movement. In this way, understanding PKA signaling in migration is a study in context and in the elegant coordination of distinct functions of a single protein in a complex cellular process.
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Affiliation(s)
- Kathryn V. Svec
- Department of Pharmacology, University of Vermont, Burlington, VT, United States
| | - Alan K. Howe
- Department of Pharmacology, University of Vermont, Burlington, VT, United States
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, V T, United States
- University of Vermont Cancer Center, University of Vermont, Burlington, VT, United States
- *Correspondence: Alan K. Howe,
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47
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Omar MH, Byrne DP, Jones KN, Lakey TM, Collins KB, Lee KS, Daly LA, Forbush KA, Lau HT, Golkowski M, McKnight GS, Breault DT, Lefrançois-Martinez AM, Martinez A, Eyers CE, Baird GS, Ong SE, Smith FD, Eyers PA, Scott JD. Mislocalization of protein kinase A drives pathology in Cushing's syndrome. Cell Rep 2022; 40:111073. [PMID: 35830806 PMCID: PMC9311266 DOI: 10.1016/j.celrep.2022.111073] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/20/2022] [Accepted: 06/17/2022] [Indexed: 01/15/2023] Open
Abstract
Mutations in the catalytic subunit of protein kinase A (PKAc) drive the stress hormone disorder adrenal Cushing's syndrome. We define mechanisms of action for the PKAc-L205R and W196R variants. Proximity proteomic techniques demonstrate that both Cushing's mutants are excluded from A kinase-anchoring protein (AKAP)-signaling islands, whereas live-cell photoactivation microscopy reveals that these kinase mutants indiscriminately diffuse throughout the cell. Only cAMP analog drugs that displace native PKAc from AKAPs enhance cortisol release. Rescue experiments that incorporate PKAc mutants into AKAP complexes abolish cortisol overproduction, indicating that kinase anchoring restores normal endocrine function. Analyses of adrenal-specific PKAc-W196R knockin mice and Cushing's syndrome patient tissue reveal defective signaling mechanisms of the disease. Surprisingly each Cushing's mutant engages a different mitogenic-signaling pathway, with upregulation of YAP/TAZ by PKAc-L205R and ERK kinase activation by PKAc-W196R. Thus, aberrant spatiotemporal regulation of each Cushing's variant promotes the transmission of distinct downstream pathogenic signals.
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Affiliation(s)
- Mitchell H Omar
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA.
| | - Dominic P Byrne
- Department of Biochemistry & Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Kiana N Jones
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Tyler M Lakey
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Kerrie B Collins
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Kyung-Soon Lee
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Leonard A Daly
- Centre for Proteome Research, Department of Biochemistry and Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Katherine A Forbush
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Ho-Tak Lau
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Martin Golkowski
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - G Stanley McKnight
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Anne-Marie Lefrançois-Martinez
- Génétique, Reproduction et Développement (GReD), CNRS, INSERM, Université Clermont Auvergne, 63001 Clermont-Ferrand, France
| | - Antoine Martinez
- Génétique, Reproduction et Développement (GReD), CNRS, INSERM, Université Clermont Auvergne, 63001 Clermont-Ferrand, France
| | - Claire E Eyers
- Centre for Proteome Research, Department of Biochemistry and Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Geoffrey S Baird
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA
| | - Shao-En Ong
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - F Donelson Smith
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Patrick A Eyers
- Department of Biochemistry & Systems Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - John D Scott
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA.
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48
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Yeast Protein Kinase A Isoforms: A Means of Encoding Specificity in the Response to Diverse Stress Conditions? Biomolecules 2022; 12:biom12070958. [PMID: 35883514 PMCID: PMC9313097 DOI: 10.3390/biom12070958] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 02/07/2023] Open
Abstract
Eukaryotic cells have developed a complex circuitry of signalling molecules which monitor changes in their intra- and extracellular environments. One of the most widely studied signalling pathways is the highly conserved cyclic AMP (cAMP)/protein kinase A (PKA) pathway, which is a major glucose sensing circuit in the yeast Saccharomyces cerevisiae. PKA activity regulates diverse targets in yeast, positively activating the processes that are associated with rapid cell growth (e.g., fermentative metabolism, ribosome biogenesis and cell division) and negatively regulating the processes that are associated with slow growth, such as respiratory growth, carbohydrate storage and entry into stationary phase. As in higher eukaryotes, yeast has evolved complexity at the level of the PKA catalytic subunit, and Saccharomyces cerevisiae expresses three isoforms, denoted Tpk1-3. Despite evidence for isoform differences in multiple biological processes, the molecular basis of PKA signalling specificity remains poorly defined, and many studies continue to assume redundancy with regards to PKA-mediated regulation. PKA has canonically been shown to play a key role in fine-tuning the cellular response to diverse stressors; however, recent studies have now begun to interrogate the requirement for individual PKA catalytic isoforms in coordinating distinct steps in stress response pathways. In this review, we discuss the known non-redundant functions of the Tpk catalytic subunits and the evolving picture of how these isoforms establish specificity in the response to different stress conditions.
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49
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Harris JA, Fairweather E, Byrne DP, Eyers PA. Analysis of human Tribbles 2 (TRIB2) pseudokinase. Methods Enzymol 2022; 667:79-99. [PMID: 35525562 DOI: 10.1016/bs.mie.2022.03.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Human Tribbles 2 (TRIB2) is a cancer-associated pseudokinase with a broad human protein interactome, including the well-studied AKT, C/EBPα and MAPK modules. Several lines of evidence indicate that human TRIB2 promotes cell survival and drug-resistance in solid tumors and blood cancers and is therefore of interest as a potential therapeutic target, although its physiological functions remain relatively poorly understood. The unique TRIB2 pseudokinase domain lacks the canonical 'DFG' motif, and subsequently possesses very low affinity for ATP in both the presence and absence of metal ions. However, TRIB2 also contains a unique cysteine-rich αC-helix, which interacts with a conserved peptide motif in its own carboxyl-terminal tail. This regulatory flanking region drives regulated interactions with distinct E3 ubiquitin ligases that serve to control the stability and turnover of TRIB2 client proteins. TRIB2 is also a low-affinity target of several known small-molecule protein kinase inhibitors, which were originally identified using purified recombinant TRIB2 proteins and a thermal shift assay. In this chapter, we discuss laboratory-based procedures for purification, stabilization and analysis of human TRIB2, including screening procedures that can be used for the identification of both reversible and covalent small molecule ligands.
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Affiliation(s)
- John A Harris
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Emma Fairweather
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Dominic P Byrne
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Patrick A Eyers
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom.
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50
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Dinh TA, Utria AF, Barry KC, Ma R, Abou-Alfa GK, Gordan JD, Jaffee EM, Scott JD, Zucman-Rossi J, O’Neill AF, Furth ME, Sethupathy P. A framework for fibrolamellar carcinoma research and clinical trials. Nat Rev Gastroenterol Hepatol 2022; 19:328-342. [PMID: 35190728 PMCID: PMC9516439 DOI: 10.1038/s41575-022-00580-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/13/2022] [Indexed: 12/17/2022]
Abstract
Fibrolamellar carcinoma (FLC), a rare, lethal hepatic cancer, occurs primarily in adolescents and young adults. Unlike hepatocellular carcinoma, FLC has no known association with viral, metabolic or chemical agents that cause cirrhosis. Currently, surgical resection is the only treatment demonstrated to achieve cure, and no standard of care exists for systemic therapy. Progress in FLC research illuminates a transition from an obscure cancer to one for which an interactive community seems poised to uncover fundamental mechanisms and initiate translation towards novel therapies. In this Roadmap, we review advances since the seminal discovery in 2014 that nearly all FLC tumours express a signature oncogene (DNAJB1-PRKACA) encoding a fusion protein (DNAJ-PKAc) in which the J-domain of a heat shock protein 40 (HSP40) co-chaperone replaces an amino-terminal segment of the catalytic subunit of the cyclic AMP-dependent protein kinase (PKA). Important gains include increased understanding of oncogenic pathways driven by DNAJ-PKAc; identification of potential therapeutic targets; development of research models; elucidation of immune mechanisms with potential for the development of immunotherapies; and completion of the first multicentre clinical trials of targeted therapy for FLC. In each of these key areas we propose a Roadmap for future progress.
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Affiliation(s)
- Timothy A. Dinh
- Medical Scientist Training Program, University of North Carolina, Chapel Hill, NC, USA.,Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA.,These authors contributed equally: Timothy A. Dinh, Alan F. Utria, Kevin C. Barry
| | - Alan F. Utria
- Department of Surgery, University of Washington, Seattle, WA, USA.,These authors contributed equally: Timothy A. Dinh, Alan F. Utria, Kevin C. Barry
| | - Kevin C. Barry
- Translational Research Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,These authors contributed equally: Timothy A. Dinh, Alan F. Utria, Kevin C. Barry
| | - Rosanna Ma
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| | - Ghassan K. Abou-Alfa
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Department of Medicine, Weill Medical College at Cornell University, New York, NY, USA
| | - John D. Gordan
- Gastrointestinal oncology, University of California at San Francisco Comprehensive Cancer Center, San Francisco, CA, USA
| | - Elizabeth M. Jaffee
- Department of oncology, Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD, USA
| | - John D. Scott
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - Jessica Zucman-Rossi
- Centre de Recherche des Cordeliers, Sorbonne université, Inserm, Université de Paris, Functional Genomics of Solid Tumors, Paris, France
| | - Allison F. O’Neill
- Department of Paediatric Hematology/oncology, Dana-Farber Cancer Institute, Harvard University, Boston, MA, USA
| | - Mark E. Furth
- Fibrolamellar Cancer Foundation, Greenwich, CT, USA.,;
| | - Praveen Sethupathy
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA.,;
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