1
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Dea A, Pincus D. The Heat Shock Response as a Condensate Cascade. J Mol Biol 2024; 436:168642. [PMID: 38848866 PMCID: PMC11214683 DOI: 10.1016/j.jmb.2024.168642] [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: 11/07/2023] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/09/2024]
Abstract
The heat shock response (HSR) is a gene regulatory program controlling expression of molecular chaperones implicated in aging, cancer, and neurodegenerative disease. Long presumed to be activated by toxic protein aggregates, recent work suggests a new functional paradigm for the HSR in yeast. Rather than toxic aggregates, adaptive biomolecular condensates comprised of orphan ribosomal proteins (oRP) and stress granule components have been shown to be physiological chaperone clients. By titrating away the chaperones Sis1 and Hsp70 from the transcription factor Hsf1, these condensates activate the HSR. Upon release from Hsp70, Hsf1 forms spatially distinct transcriptional condensates that drive high expression of HSR genes. In this manner, the negative feedback loop controlling HSR activity - in which Hsf1 induces Hsp70 expression and Hsp70 represses Hsf1 activity - is embedded in the biophysics of the system. By analogy to phosphorylation cascades that transmit information via the dynamic activity of kinases, we propose that the HSR is organized as a condensate cascade that transmits information via the localized activity of molecular chaperones.
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Affiliation(s)
- Annisa Dea
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, United States
| | - David Pincus
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, United States; Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, United States; Center for Physics of Evolving Systems, University of Chicago, Chicago, IL, United States.
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2
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Zhao P, Wang C, Sun S, Wang X, Balch WE. Tracing genetic diversity captures the molecular basis of misfolding disease. Nat Commun 2024; 15:3333. [PMID: 38637533 PMCID: PMC11026414 DOI: 10.1038/s41467-024-47520-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 04/04/2024] [Indexed: 04/20/2024] Open
Abstract
Genetic variation in human populations can result in the misfolding and aggregation of proteins, giving rise to systemic and neurodegenerative diseases that require management by proteostasis. Here, we define the role of GRP94, the endoplasmic reticulum Hsp90 chaperone paralog, in managing alpha-1-antitrypsin deficiency on a residue-by-residue basis using Gaussian process regression-based machine learning to profile the spatial covariance relationships that dictate protein folding arising from sequence variants in the population. Covariance analysis suggests a role for the ATPase activity of GRP94 in controlling the N- to C-terminal cooperative folding of alpha-1-antitrypsin responsible for the correction of liver aggregation and lung-disease phenotypes of alpha-1-antitrypsin deficiency. Gaussian process-based spatial covariance profiling provides a standard model built on covariant principles to evaluate the role of proteostasis components in guiding information flow from genome to proteome in response to genetic variation, potentially allowing us to intervene in the onset and progression of complex multi-system human diseases.
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Affiliation(s)
- Pei Zhao
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
| | - Chao Wang
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA.
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, China.
| | - Shuhong Sun
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
- Department of Nutrition and Food Hygiene, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
- Institute for Brain Tumors, Collaborative Innovation Center for Cancer Personalized Medicine, and Center for Global Health, Nanjing Medical University, Nanjing, China
| | - Xi Wang
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - William E Balch
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA.
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3
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Montrose K, Lac DT, Burnetti AJ, Tong K, Bozdag GO, Hukkanen M, Ratcliff WC, Saarikangas J. Proteostatic tuning underpins the evolution of novel multicellular traits. SCIENCE ADVANCES 2024; 10:eadn2706. [PMID: 38457507 PMCID: PMC10923498 DOI: 10.1126/sciadv.adn2706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/06/2024] [Indexed: 03/10/2024]
Abstract
The evolution of multicellularity paved the way for the origin of complex life on Earth, but little is known about the mechanistic basis of early multicellular evolution. Here, we examine the molecular basis of multicellular adaptation in the multicellularity long-term evolution experiment (MuLTEE). We demonstrate that cellular elongation, a key adaptation underpinning increased biophysical toughness and organismal size, is convergently driven by down-regulation of the chaperone Hsp90. Mechanistically, Hsp90-mediated morphogenesis operates by destabilizing the cyclin-dependent kinase Cdc28, resulting in delayed mitosis and prolonged polarized growth. Reinstatement of Hsp90 or Cdc28 expression resulted in shortened cells that formed smaller groups with reduced multicellular fitness. Together, our results show how ancient protein folding systems can be tuned to drive rapid evolution at a new level of biological individuality by revealing novel developmental phenotypes.
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Affiliation(s)
- Kristopher Montrose
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Helsinki, Finland
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Dung T. Lac
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Anthony J. Burnetti
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Kai Tong
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Helsinki, Finland
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
- Interdisciplinary Graduate Program in Quantitative Biosciences (QBioS), Georgia Institute of Technology, Atlanta, GA, USA
| | - G. Ozan Bozdag
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Mikaela Hukkanen
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Helsinki, Finland
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - William C. Ratcliff
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Juha Saarikangas
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Helsinki, Finland
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
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4
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Garde R, Dea A, Herwig MF, Pincus D. Feedback control of the heat shock response by spatiotemporal regulation of Hsp70. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.09.574867. [PMID: 38260373 PMCID: PMC10802473 DOI: 10.1101/2024.01.09.574867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Cells maintain homeostasis via dynamic regulation of stress response pathways. Stress pathways transiently induce response regulons via negative feedback loops, but the extent to which individual genes provide feedback has not been comprehensively measured for any pathway. Here, we disrupted induction of each gene in the Saccharomyces cerevisiae heat shock response (HSR) and quantified cell growth and HSR dynamics following heat shock. The screen revealed a core feedback loop governing expression of the chaperone Hsp70 reinforced by an auxiliary feedback loop controlling Hsp70 subcellular localization. Mathematical modeling and live imaging demonstrated that multiple HSR targets converge to promote Hsp70 nuclear localization via its release from cytosolic condensates. Following ethanol stress, a distinct set of factors similarly converged on Hsp70, suggesting that nonredundant subsets of the HSR regulon confer feedback under different conditions. Flexible spatiotemporal feedback loops may broadly organize stress response regulons and expand their adaptive capacity.
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Affiliation(s)
- Rania Garde
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
- Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, IL
| | - Annisa Dea
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| | - Madeline F. Herwig
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| | - David Pincus
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL
- Center for Physics of Evolving Systems, University of Chicago, Chicago, IL
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5
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Ow MC, Hall SE. Inheritance of Stress Responses via Small Non-Coding RNAs in Invertebrates and Mammals. EPIGENOMES 2023; 8:1. [PMID: 38534792 DOI: 10.3390/epigenomes8010001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/06/2023] [Accepted: 12/12/2023] [Indexed: 03/28/2024] Open
Abstract
While reports on the generational inheritance of a parental response to stress have been widely reported in animals, the molecular mechanisms behind this phenomenon have only recently emerged. The booming interest in epigenetic inheritance has been facilitated in part by the discovery that small non-coding RNAs are one of its principal conduits. Discovered 30 years ago in the Caenorhabditis elegans nematode, these small molecules have since cemented their critical roles in regulating virtually all aspects of eukaryotic development. Here, we provide an overview on the current understanding of epigenetic inheritance in animals, including mice and C. elegans, as it pertains to stresses such as temperature, nutritional, and pathogenic encounters. We focus on C. elegans to address the mechanistic complexity of how small RNAs target their cohort mRNAs to effect gene expression and how they govern the propagation or termination of generational perdurance in epigenetic inheritance. Presently, while a great amount has been learned regarding the heritability of gene expression states, many more questions remain unanswered and warrant further investigation.
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Affiliation(s)
- Maria C Ow
- Department of Biology, Syracuse University, Syracuse, NY 13210, USA
| | - Sarah E Hall
- Department of Biology and Program in Neuroscience, Syracuse University, Syracuse, NY 13210, USA
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6
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Singh A, Saint-Antoine M. Probing transient memory of cellular states using single-cell lineages. Front Microbiol 2023; 13:1050516. [PMID: 36824587 PMCID: PMC9942930 DOI: 10.3389/fmicb.2022.1050516] [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: 09/21/2022] [Accepted: 12/22/2022] [Indexed: 02/10/2023] Open
Abstract
The inherent stochasticity in the gene product levels can drive single cells within an isoclonal population to different phenotypic states. The dynamic nature of this intercellular variation, where individual cells can transition between different states over time, makes it a particularly hard phenomenon to characterize. We reviewed recent progress in leveraging the classical Luria-Delbrück experiment to infer the transient heritability of the cellular states. Similar to the original experiment, individual cells were first grown into cell colonies, and then, the fraction of cells residing in different states was assayed for each colony. We discuss modeling approaches for capturing dynamic state transitions in a growing cell population and highlight formulas that identify the kinetics of state switching from the extent of colony-to-colony fluctuations. The utility of this method in identifying multi-generational memory of the both expression and phenotypic states is illustrated across diverse biological systems from cancer drug resistance, reactivation of human viruses, and cellular immune responses. In summary, this fluctuation-based methodology provides a powerful approach for elucidating cell-state transitions from a single time point measurement, which is particularly relevant in situations where measurements lead to cell death (as in single-cell RNA-seq or drug treatment) or cause an irreversible change in cell physiology.
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Affiliation(s)
- Abhyudai Singh
- Departments of Electrical and Computer Engineering, Biomedical Engineering, Mathematical Sciences University of Delaware, Newark, DE, United States
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7
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Chowdhary S, Kainth AS, Paracha S, Gross DS, Pincus D. Inducible transcriptional condensates drive 3D genome reorganization in the heat shock response. Mol Cell 2022; 82:4386-4399.e7. [PMID: 36327976 PMCID: PMC9701134 DOI: 10.1016/j.molcel.2022.10.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 08/28/2022] [Accepted: 10/10/2022] [Indexed: 11/12/2022]
Abstract
Mammalian developmental and disease-associated genes concentrate large quantities of the transcriptional machinery by forming membrane-less compartments known as transcriptional condensates. However, it is unknown whether these structures are evolutionarily conserved or involved in 3D genome reorganization. Here, we identify inducible transcriptional condensates in the yeast heat shock response (HSR). HSR condensates are biophysically dynamic spatiotemporal clusters of the sequence-specific transcription factor heat shock factor 1 (Hsf1) with Mediator and RNA Pol II. Uniquely, HSR condensates drive the coalescence of multiple Hsf1 target genes, even those located on different chromosomes. Binding of the chaperone Hsp70 to a site on Hsf1 represses clustering, whereas an intrinsically disordered region on Hsf1 promotes condensate formation and intergenic interactions. Mutation of both Hsf1 determinants reprograms HSR condensates to become constitutively active without intergenic coalescence, which comes at a fitness cost. These results suggest that transcriptional condensates are ancient and flexible compartments of eukaryotic gene control.
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Affiliation(s)
- Surabhi Chowdhary
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Amoldeep S Kainth
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA
| | - Sarah Paracha
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - David S Gross
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA.
| | - David Pincus
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA; Center for Physics of Evolving Systems, University of Chicago, Chicago, IL 60637, USA.
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8
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Palenchar PM, DeStefanis T. Transcriptional noise adjusted for expression levels reveals genes with high transcriptional noise that are highly expressed, functionally related, and co-regulated in yeast. Curr Genet 2022; 68:675-686. [PMID: 36245041 DOI: 10.1007/s00294-022-01255-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/16/2022] [Accepted: 09/17/2022] [Indexed: 11/26/2022]
Abstract
Understanding the relationship between variability in single-cell and non-single-cell gene expression studies will aid in understanding the role of and mechanisms that lead to variability in biological systems. Studies on the variation of gene expression levels in yeast normally focus on single cells and use the coefficient of variance (CV) as a measure of noise. The CV is typically negatively correlated with gene expression levels, so most of the studies using yeast find that genes with high transcriptional noise are lowly expressed. We find adjusting noise for expression levels using linear/natural log polynomial, and local fits and analyzing many non-single-cell RNA-seq sets identifies genes with high median transcriptional noise that are different than those that have high median CVs. Interestingly, these genes are heavily regulated by transcription factors that are related to variability and stochastic processes based on single-cell studies, including Msn2p, Msn4p, Hsf1p, and Crz1p but are not associated with genes with high median CVs based on non-single-cell gene expression data. In addition, adjusting noise for expression levels in a single-cell RNA-seq data set adds value by finding genes that have noisy gene expression levels and their associated transcription factors that are not found to be associated with genes with high CVs in the single-cell expression data or a comparable non-single-cell gene expression data. Lastly, S. cerevisiae genes with noisy expression tend to have orthologs with noisy gene expression in C. albicans, indicating transcriptional noise is evolutionarily conserved.
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9
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Torii S, Rakic P. Tracking the Activation of Heat Shock Signaling in Cellular Protection and Damage. Cells 2022; 11:1561. [PMID: 35563865 PMCID: PMC9104565 DOI: 10.3390/cells11091561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/02/2022] [Accepted: 05/02/2022] [Indexed: 01/27/2023] Open
Abstract
Heat Shock (HS) signaling is activated in response to various types of cellular stress. This activation serves to protect cells from immediate threats in the surrounding environment. However, activation of HS signaling occurs in a heterogeneous manner within each cell population and can alter the epigenetic state of the cell, ultimately leading to long-term abnormalities in body function. Here, we summarize recent research findings obtained using molecular and genetic tools to track cells where HS signaling is activated. We then discuss the potential further applications of these tools, their limitations, and the necessary caveats in interpreting data obtained with these tools.
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Affiliation(s)
| | - Pasko Rakic
- Department of Neuroscience, School of Medicine, Yale University, New Haven, CT 06510, USA;
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10
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Dekker FA, Rüdiger SGD. The Mitochondrial Hsp90 TRAP1 and Alzheimer's Disease. Front Mol Biosci 2021; 8:697913. [PMID: 34222342 PMCID: PMC8249562 DOI: 10.3389/fmolb.2021.697913] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 06/02/2021] [Indexed: 12/31/2022] Open
Abstract
Alzheimer’s Disease (AD) is the most common form of dementia, characterised by intra- and extracellular protein aggregation. In AD, the cellular protein quality control (PQC) system is derailed and fails to prevent the formation of these aggregates. Especially the mitochondrial paralogue of the conserved Hsp90 chaperone class, tumour necrosis factor receptor-associated protein 1 (TRAP1), is strongly downregulated in AD, more than other major PQC factors. Here, we review molecular mechanism and cellular function of TRAP1 and subsequently discuss possible links to AD. TRAP1 is an interesting paradigm for the Hsp90 family, as it chaperones proteins with vital cellular function, despite not being regulated by any of the co-chaperones that drive its cytosolic paralogues. TRAP1 encloses late folding intermediates in a non-active state. Thereby, it is involved in the assembly of the electron transport chain, and it favours the switch from oxidative phosphorylation to glycolysis. Another key function is that it ensures mitochondrial integrity by regulating the mitochondrial pore opening through Cyclophilin D. While it is still unclear whether TRAP1 itself is a driver or a passenger in AD, it might be a guide to identify key factors initiating neurodegeneration.
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Affiliation(s)
- Françoise A Dekker
- Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,Cellular Protein Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, Netherlands.,Science for Life, Utrecht University, Utrecht, Netherlands
| | - Stefan G D Rüdiger
- Cellular Protein Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, Netherlands.,Science for Life, Utrecht University, Utrecht, Netherlands
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11
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Lang BJ, Guerrero ME, Prince TL, Okusha Y, Bonorino C, Calderwood SK. The functions and regulation of heat shock proteins; key orchestrators of proteostasis and the heat shock response. Arch Toxicol 2021; 95:1943-1970. [PMID: 34003342 DOI: 10.1007/s00204-021-03070-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 05/03/2021] [Indexed: 12/14/2022]
Abstract
Cells respond to protein-damaging (proteotoxic) stress by activation of the Heat Shock Response (HSR). The HSR provides cells with an enhanced ability to endure proteotoxic insults and plays a crucial role in determining subsequent cell death or survival. The HSR is, therefore, a critical factor that influences the toxicity of protein stress. While named for its vital role in the cellular response to heat stress, various components of the HSR system and the molecular chaperone network execute essential physiological functions as well as responses to other diverse toxic insults. The effector molecules of the HSR, the Heat Shock Factors (HSFs) and Heat Shock Proteins (HSPs), are also important regulatory targets in the progression of neurodegenerative diseases and cancers. Modulation of the HSR and/or its extended network have, therefore, become attractive treatment strategies for these diseases. Development of effective therapies will, however, require a detailed understanding of the HSR, important features of which continue to be uncovered and are yet to be completely understood. We review recently described and hallmark mechanistic principles of the HSR, the regulation and functions of HSPs, and contexts in which the HSR is activated and influences cell fate in response to various toxic conditions.
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Affiliation(s)
- Benjamin J Lang
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Martin E Guerrero
- Laboratory of Oncology, Institute of Medicine and Experimental Biology of Cuyo (IMBECU), National Scientific and Technical Research Council (CONICET), 5500, Mendoza, Argentina
| | - Thomas L Prince
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Yuka Okusha
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Cristina Bonorino
- Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brasil.,Department of Surgery, School of Medicine, University of California, La Jolla, San Diego, CA, 92093, USA
| | - Stuart K Calderwood
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA.
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12
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Feder ZA, Ali A, Singh A, Krakowiak J, Zheng X, Bindokas VP, Wolfgeher D, Kron SJ, Pincus D. Subcellular localization of the J-protein Sis1 regulates the heat shock response. J Cell Biol 2021; 220:211600. [PMID: 33326013 PMCID: PMC7748816 DOI: 10.1083/jcb.202005165] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 10/13/2020] [Accepted: 11/06/2020] [Indexed: 12/24/2022] Open
Abstract
Cells exposed to heat shock induce a conserved gene expression program, the heat shock response (HSR), encoding protein homeostasis (proteostasis) factors. Heat shock also triggers proteostasis factors to form subcellular quality control bodies, but the relationship between these spatial structures and the HSR is unclear. Here we show that localization of the J-protein Sis1, a cofactor for the chaperone Hsp70, controls HSR activation in yeast. Under nonstress conditions, Sis1 is concentrated in the nucleoplasm, where it promotes Hsp70 binding to the transcription factor Hsf1, repressing the HSR. Upon heat shock, Sis1 forms an interconnected network with other proteostasis factors that spans the nucleolus and the surface of the endoplasmic reticulum. We propose that localization of Sis1 to this network directs Hsp70 activity away from Hsf1 in the nucleoplasm, leaving Hsf1 free to induce the HSR. In this manner, Sis1 couples HSR activation to the spatial organization of the proteostasis network.
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Affiliation(s)
- Zoë A Feder
- Whitehead Institute for Biomedical Research, Cambridge, MA
| | - Asif Ali
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| | - Abhyudai Singh
- Department of Electrical and Computer Engineering, University of Delaware, Newark, DE.,Department of Biomedical Engineering, University of Delaware, Newark, DE.,Department of Mathematical Sciences, University of Delaware, Newark, DE.,Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE
| | | | - Xu Zheng
- Whitehead Institute for Biomedical Research, Cambridge, MA.,State Key Laboratory of Wheat and Maize Crop Science, College of Agronomy, Henan Agricultural University, Zhengzhou, China
| | - Vytas P Bindokas
- Integrated Light Microscopy Core Facility, University of Chicago, Chicago, IL
| | - Donald Wolfgeher
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| | - Stephen J Kron
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL
| | - David Pincus
- Whitehead Institute for Biomedical Research, Cambridge, MA.,Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL.,Center for Physics of Evolving Systems, University of Chicago, Chicago, IL
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13
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Houri-Zeevi L, Korem Kohanim Y, Antonova O, Rechavi O. Three Rules Explain Transgenerational Small RNA Inheritance in C. elegans. Cell 2020; 182:1186-1197.e12. [PMID: 32841602 PMCID: PMC7479518 DOI: 10.1016/j.cell.2020.07.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 05/21/2020] [Accepted: 07/17/2020] [Indexed: 02/06/2023]
Abstract
Experiences trigger transgenerational small RNA-based responses in C. elegans nematodes. Dedicated machinery ensures that heritable effects are reset, but how the responses segregate in the population is unknown. We show that isogenic individuals differ dramatically in the persistence of transgenerational responses. By examining lineages of more than 20,000 worms, three principles emerge: (1) The silencing each mother initiates is distributed evenly among her descendants; heritable RNAi dissipates but is uniform in every generation. (2) Differences between lineages arise because the mothers that initiate heritable responses stochastically assume different "inheritance states" that determine the progeny's fate. (3) The likelihood that an RNAi response would continue to be inherited increases the more generations it lasts. The inheritance states are determined by HSF-1, which regulates silencing factors and, accordingly, small RNA levels. We found that, based on the parents' inheritance state, the descendants' developmental rate in response to stress can be predicted.
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Affiliation(s)
- Leah Houri-Zeevi
- Department of Neurobiology, Wise Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Yael Korem Kohanim
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Olga Antonova
- Department of Neurobiology, Wise Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Oded Rechavi
- Department of Neurobiology, Wise Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel.
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14
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Santiago AM, Gonçalves DL, Morano KA. Mechanisms of sensing and response to proteotoxic stress. Exp Cell Res 2020; 395:112240. [PMID: 32827554 DOI: 10.1016/j.yexcr.2020.112240] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 08/13/2020] [Accepted: 08/18/2020] [Indexed: 12/25/2022]
Abstract
Cells are continuously subject to various stresses, battling both exogenous insults as well as toxic by-products of normal cellular metabolism and nutrient deprivation. Throughout the millennia, cells developed a core set of general stress responses that promote survival and reproduction under adverse circumstances. Past and current research efforts have been devoted to understanding how cells sense stressors and how that input is deciphered and transduced, resulting in stimulation of stress management pathways. A prime element of cellular stress responses is the increased transcription and translation of proteins specialized in managing and mitigating distinct types of stress. In this review, we focus on recent developments in our understanding of cellular sensing of proteotoxic stressors that impact protein synthesis, folding, and maturation provided by the model eukaryote the budding yeast, Saccharomyces cerevisiae, with reference to similarities and differences with other model organisms and humans.
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Affiliation(s)
- Alec M Santiago
- Department of Microbiology and Molecular Genetics, McGovern Medical School, UTHealth, Houston, TX, 77030, USA; MD Anderson UTHealth Graduate School of Biomedical Sciences, UTHealth, Houston, TX, 77030, USA
| | - Davi L Gonçalves
- Department of Microbiology and Molecular Genetics, McGovern Medical School, UTHealth, Houston, TX, 77030, USA
| | - Kevin A Morano
- Department of Microbiology and Molecular Genetics, McGovern Medical School, UTHealth, Houston, TX, 77030, USA.
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15
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Pincus D. Regulation of Hsf1 and the Heat Shock Response. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1243:41-50. [PMID: 32297210 DOI: 10.1007/978-3-030-40204-4_3] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The heat shock response (HSR) is characterized by the induction of molecular chaperones following a sudden increase in temperature. In eukaryotes, the HSR comprises the set of genes controlled by the transcription factor Hsf1. The HSR is induced by defects in co-translational protein folding, ribosome biogenesis, organellar targeting of nascent proteins, and protein degradation by the ubiquitin proteasome system. Upon heat shock, these processes may be endogenous sources of polypeptide ligands that activate the HSR. Mechanistically, these ligands are thought to titrate the chaperone Hsp70 away from Hsf1, releasing Hsf1 to induce the full arsenal of cellular chaperones to restore protein homeostasis. In metazoans, this cell-autonomous feedback loop is modulated by the microenvironment and neuronal cues to enable tissue-level and organism-wide coordination.
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Affiliation(s)
- David Pincus
- Department of Molecular Genetics and Cell Biology, Center for Physics of Evolving Systems, University of Chicago, Chicago, IL, USA.
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16
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Prince TL, Lang BJ, Guerrero-Gimenez ME, Fernandez-Muñoz JM, Ackerman A, Calderwood SK. HSF1: Primary Factor in Molecular Chaperone Expression and a Major Contributor to Cancer Morbidity. Cells 2020; 9:E1046. [PMID: 32331382 PMCID: PMC7226471 DOI: 10.3390/cells9041046] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/17/2020] [Accepted: 04/19/2020] [Indexed: 02/07/2023] Open
Abstract
Heat shock factor 1 (HSF1) is the primary component for initiation of the powerful heat shock response (HSR) in eukaryotes. The HSR is an evolutionarily conserved mechanism for responding to proteotoxic stress and involves the rapid expression of heat shock protein (HSP) molecular chaperones that promote cell viability by facilitating proteostasis. HSF1 activity is amplified in many tumor contexts in a manner that resembles a chronic state of stress, characterized by high levels of HSP gene expression as well as HSF1-mediated non-HSP gene regulation. HSF1 and its gene targets are essential for tumorigenesis across several experimental tumor models, and facilitate metastatic and resistant properties within cancer cells. Recent studies have suggested the significant potential of HSF1 as a therapeutic target and have motivated research efforts to understand the mechanisms of HSF1 regulation and develop methods for pharmacological intervention. We review what is currently known regarding the contribution of HSF1 activity to cancer pathology, its regulation and expression across human cancers, and strategies to target HSF1 for cancer therapy.
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Affiliation(s)
- Thomas L. Prince
- Department of Molecular Functional Genomics, Geisinger Clinic, Danville, PA 17821, USA
| | - Benjamin J. Lang
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Martin E. Guerrero-Gimenez
- Laboratory of Oncology, Institute of Medicine and Experimental Biology of Cuyo (IMBECU), National Scientific and Technical Research Council (CONICET), Buenos Aires B1657, Argentina
| | - Juan Manuel Fernandez-Muñoz
- Laboratory of Oncology, Institute of Medicine and Experimental Biology of Cuyo (IMBECU), National Scientific and Technical Research Council (CONICET), Buenos Aires B1657, Argentina
| | - Andrew Ackerman
- Department of Molecular Functional Genomics, Geisinger Clinic, Danville, PA 17821, USA
| | - Stuart K. Calderwood
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
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17
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Guilbert M, Anquez F, Pruvost A, Thommen Q, Courtade E. Protein level variability determines phenotypic heterogeneity in proteotoxic stress response. FEBS J 2020; 287:5345-5361. [PMID: 32222033 DOI: 10.1111/febs.15297] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 02/03/2020] [Accepted: 03/16/2020] [Indexed: 01/19/2023]
Abstract
Cell-to-cell variability in stress response is a bottleneck for the construction of accurate and predictive models which could guide clinical diagnosis and treatment of certain diseases, for example, cancer. Indeed, such phenotypic heterogeneity can lead to fractional killing and persistence of a subpopulation of cells which are resistant to a given treatment. The heat shock response network plays a major role in protecting the proteome against several types of injuries. Here, we combine high-throughput measurements and mathematical modeling to unveil the molecular origin of the phenotypic variability in the heat shock response network. Although the mean response coincides with known biochemical measurements, we found a surprisingly broad diversity in single-cell dynamics with a continuum of response amplitudes and temporal shapes for several stimulus strengths. We theoretically predict that the broad phenotypic heterogeneity is due to network ultrasensitivity together with variations in the expression level of chaperones controlled by the transcription factor heat shock factor 1. Furthermore, we experimentally confirm this prediction by mapping the response amplitude to chaperone and heat shock factor 1 expression levels.
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Affiliation(s)
- Marie Guilbert
- UMR 8523, PhLAM - Physique des Lasers Atomes et Molécules, CNRS, Université de Lille, France
| | - François Anquez
- UMR 8523, PhLAM - Physique des Lasers Atomes et Molécules, CNRS, Université de Lille, France
| | - Alexandra Pruvost
- UMR 8523, PhLAM - Physique des Lasers Atomes et Molécules, CNRS, Université de Lille, France
| | - Quentin Thommen
- UMR 8523, PhLAM - Physique des Lasers Atomes et Molécules, CNRS, Université de Lille, France
| | - Emmanuel Courtade
- UMR 8523, PhLAM - Physique des Lasers Atomes et Molécules, CNRS, Université de Lille, France
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18
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Abstract
Protein folding in the cell is mediated by an extensive network of >1,000 chaperones, quality control factors, and trafficking mechanisms collectively termed the proteostasis network. While the components and organization of this network are generally well established, our understanding of how protein-folding problems are identified, how the network components integrate to successfully address challenges, and what types of biophysical issues each proteostasis network component is capable of addressing remains immature. We describe a chemical biology-informed framework for studying cellular proteostasis that relies on selection of interesting protein-folding problems and precise researcher control of proteostasis network composition and activities. By combining these methods with multifaceted strategies to monitor protein folding, degradation, trafficking, and aggregation in cells, researchers continue to rapidly generate new insights into cellular proteostasis.
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Affiliation(s)
- Rebecca M Sebastian
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA;
| | - Matthew D Shoulders
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA;
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19
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Biebl MM, Buchner J. Structure, Function, and Regulation of the Hsp90 Machinery. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a034017. [PMID: 30745292 DOI: 10.1101/cshperspect.a034017] [Citation(s) in RCA: 166] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Heat shock protein 90 (Hsp90) is a molecular chaperone involved in the maturation of a plethora of substrates ("clients"), including protein kinases, transcription factors, and E3 ubiquitin ligases, positioning Hsp90 as a central regulator of cellular proteostasis. Hsp90 undergoes large conformational changes during its ATPase cycle. The processing of clients by cytosolic Hsp90 is assisted by a cohort of cochaperones that affect client recruitment, Hsp90 ATPase function or conformational rearrangements in Hsp90. Because of the importance of Hsp90 in regulating central cellular pathways, strategies for the pharmacological inhibition of the Hsp90 machinery in diseases such as cancer and neurodegeneration are being developed. In this review, we summarize recent structural and mechanistic progress in defining the function of organelle-specific and cytosolic Hsp90, including the impact of individual cochaperones on the maturation of specific clients and complexes with clients as well as ways of exploiting Hsp90 as a drug target.
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Affiliation(s)
- Maximilian M Biebl
- Center for Integrated Protein Science, Department of Chemistry, Technische Universität München, D-85748 Garching, Germany
| | - Johannes Buchner
- Center for Integrated Protein Science, Department of Chemistry, Technische Universität München, D-85748 Garching, Germany
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20
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Joutsen J, Sistonen L. Tailoring of Proteostasis Networks with Heat Shock Factors. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a034066. [PMID: 30420555 DOI: 10.1101/cshperspect.a034066] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Heat shock factors (HSFs) are the main transcriptional regulators of the heat shock response and indispensable for maintaining cellular proteostasis. HSFs mediate their protective functions through diverse genetic programs, which are composed of genes encoding molecular chaperones and other genes crucial for cell survival. The mechanisms that are used to tailor HSF-driven proteostasis networks are not yet completely understood, but they likely comprise from distinct combinations of both genetic and proteomic determinants. In this review, we highlight the versatile HSF-mediated cellular functions that extend from cellular stress responses to various physiological and pathological processes, and we underline the key advancements that have been achieved in the field of HSF research during the last decade.
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Affiliation(s)
- Jenny Joutsen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, 20520 Turku, Finland.,Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, 20520 Turku, Finland
| | - Lea Sistonen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, 20520 Turku, Finland.,Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, 20520 Turku, Finland
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21
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Knorre DA, Azbarova AV, Galkina KV, Feniouk BA, Severin FF. Replicative aging as a source of cell heterogeneity in budding yeast. Mech Ageing Dev 2018; 176:24-31. [DOI: 10.1016/j.mad.2018.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 09/18/2018] [Accepted: 09/19/2018] [Indexed: 02/06/2023]
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22
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Prostate-Associated Gene 4 (PAGE4): Leveraging the Conformational Dynamics of a Dancing Protein Cloud as a Therapeutic Target. J Clin Med 2018; 7:jcm7060156. [PMID: 29914187 PMCID: PMC6025510 DOI: 10.3390/jcm7060156] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 06/13/2018] [Accepted: 06/15/2018] [Indexed: 12/24/2022] Open
Abstract
Prostate cancer (PCa) is a leading cause of mortality and morbidity globally. While genomic alterations have been identified in PCa, in contrast to some other cancers, use of such information to personalize treatment is still in its infancy. Here, we discuss how PAGE4, a protein which appears to act both as an oncogenic factor as well as a metastasis suppressor, is a novel therapeutic target for PCa. Inhibiting PAGE4 may be a viable strategy for low-risk PCa where it is highly upregulated. Conversely, PAGE4 expression is downregulated in metastatic PCa and, therefore, reinstituting its sustained expression may be a promising option to subvert or attenuate androgen-resistant PCa. Thus, fine-tuning the levels of PAGE4 may represent a novel approach for personalized medicine in PCa.
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23
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Lin X, Roy S, Jolly MK, Bocci F, Schafer NP, Tsai MY, Chen Y, He Y, Grishaev A, Weninger K, Orban J, Kulkarni P, Rangarajan G, Levine H, Onuchic JN. PAGE4 and Conformational Switching: Insights from Molecular Dynamics Simulations and Implications for Prostate Cancer. J Mol Biol 2018; 430:2422-2438. [PMID: 29758263 DOI: 10.1016/j.jmb.2018.05.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/13/2018] [Accepted: 05/07/2018] [Indexed: 11/15/2022]
Abstract
Prostate-associated gene 4 (PAGE4) is an intrinsically disordered protein implicated in prostate cancer. Thestress-response kinase homeodomain-interacting protein kinase 1 (HIPK1) phosphorylates two residues in PAGE4, serine 9 and threonine 51. Phosphorylation of these two residues facilitates the interaction of PAGE4 with activator protein-1 (AP-1) transcription factor complex to potentiate AP-1's activity. In contrast, hyperphosphorylation of PAGE4 by CDC-like kinase 2 (CLK2) attenuates this interaction with AP-1. Small-angleX-ray scattering and single-molecule fluorescence resonance energy transfer measurements have shown that PAGE4 expands upon hyperphosphorylation and that this expansion is localized to its N-terminal half. To understand the interactions underlying this structural transition, we performed molecular dynamics simulations using Atomistic AWSEM, a multi-scale molecular model that combines atomistic and coarse-grained simulation approaches. Our simulations show that electrostatic interactions drive transient formation of an N-terminal loop, the destabilization of which accounts for the dramatic change in size upon hyperphosphorylation. Phosphorylation also changes the preference of secondary structure formation of the PAGE4 ensemble, which leads to a transition between states that display different degrees of disorder. Finally, we construct a mechanism-based mathematical model that allows us to capture the interactions ofdifferent phosphoforms of PAGE4 with AP-1 and its downstream target, the androgen receptor (AR)-a key therapeutic target in prostate cancer. Our model predicts intracellular oscillatory dynamics of HIPK1-PAGE4, CLK2-PAGE4, and AR activity, indicating phenotypic heterogeneity in an isogenic cell population. Thus, conformational switching of PAGE4 may potentially affect the efficiency of therapeutically targeting AR activity.
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Affiliation(s)
- Xingcheng Lin
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States; Department of Physics and Astronomy, Rice University, Houston, TX 77005, United States
| | - Susmita Roy
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States
| | - Mohit Kumar Jolly
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States
| | - Federico Bocci
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States; Department of Chemistry, Rice University, Houston, TX 77005, United States
| | - Nicholas P Schafer
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States; Department of Chemistry, Rice University, Houston, TX 77005, United States
| | - Min-Yeh Tsai
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States; Department of Chemistry, Rice University, Houston, TX 77005, United States
| | - Yihong Chen
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, United States
| | - Yanan He
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, United States
| | - Alexander Grishaev
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, United States; National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Keith Weninger
- Department of Physics, North Carolina State University, Raleigh, NC 27695, United States
| | - John Orban
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, United States; Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, United States
| | - Prakash Kulkarni
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, United States; Department of Medical Oncology and Therapeutics Research, City of Hope National Medical Center, Duarte, CA 91010, United States
| | - Govindan Rangarajan
- Department of Mathematics, Indian Institute of Science, Bangalore 560012, India; Center for Neuroscience, Indian Institute of Science, Bangalore 560012, India
| | - Herbert Levine
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States; Department of Physics and Astronomy, Rice University, Houston, TX 77005, United States
| | - José N Onuchic
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, United States; Department of Physics and Astronomy, Rice University, Houston, TX 77005, United States; Department of Chemistry, Rice University, Houston, TX 77005, United States; Department of BioSciences, Rice University, Houston, TX 77005, United States.
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