1
|
Tokareva OS, Li K, Travaline TL, Thomson TM, Swiecicki JM, Moussa M, Ramirez JD, Litchman S, Verdine GL, McGee JH. Recognition and reprogramming of E3 ubiquitin ligase surfaces by α-helical peptides. Nat Commun 2023; 14:6992. [PMID: 37914719 PMCID: PMC10620186 DOI: 10.1038/s41467-023-42395-z] [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: 08/01/2023] [Accepted: 10/09/2023] [Indexed: 11/03/2023] Open
Abstract
Molecules that induce novel interactions between proteins hold great promise for the study of biological systems and the development of therapeutics, but their discovery has been limited by the complexities of rationally designing interactions between three components, and because known binders to each protein are typically required to inform initial designs. Here, we report a general and rapid method for discovering α-helically constrained (Helicon) polypeptides that cooperatively induce the interaction between two target proteins without relying on previously known binders or an intrinsic affinity between the proteins. We show that Helicons are capable of binding every major class of E3 ubiquitin ligases, which are of great biological and therapeutic interest but remain largely intractable to targeting by small molecules. We then describe a phage-based screening method for discovering "trimerizer" Helicons, and apply it to reprogram E3s to cooperatively bind an enzyme (PPIA), a transcription factor (TEAD4), and a transcriptional coactivator (β-catenin).
Collapse
Affiliation(s)
| | - Kunhua Li
- FOG Pharmaceuticals Inc., Cambridge, MA, USA
- Kymera Therapeutics, Inc., Watertown, MA, USA
| | | | | | - Jean-Marie Swiecicki
- FOG Pharmaceuticals Inc., Cambridge, MA, USA
- Relay Therapeutics, Inc., Cambridge, MA, USA
| | | | | | | | - Gregory L Verdine
- FOG Pharmaceuticals Inc., Cambridge, MA, USA.
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA.
- Department of Chemistry and Chemical Biology, Harvard, University, Cambridge, MA, USA.
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA.
| | | |
Collapse
|
2
|
Nadel CM, Wucherer K, Oehler A, Thwin AC, Basu K, Callahan MD, Southworth DR, Mordes DA, Craik CS, Gestwicki JE. Phosphorylation of a Cleaved Tau Proteoform at a Single Residue Inhibits Binding to the E3 Ubiquitin Ligase, CHIP. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.16.553575. [PMID: 37645969 PMCID: PMC10462110 DOI: 10.1101/2023.08.16.553575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Microtubule-associated protein tau (MAPT/tau) accumulates in a family of neurodegenerative diseases, including Alzheimer's disease (AD). In disease, tau is aberrantly modified by post-translational modifications (PTMs), including hyper-phosphorylation. However, it is often unclear which of these PTMs contribute to tau's accumulation or what mechanisms might be involved. To explore these questions, we focused on a cleaved proteoform of tau (tauC3), which selectively accumulates in AD and was recently shown to be degraded by its direct binding to the E3 ubiquitin ligase, CHIP. Here, we find that phosphorylation of tauC3 at a single residue, pS416, is sufficient to block its interaction with CHIP. A co-crystal structure of CHIP bound to the C-terminus of tauC3 revealed the mechanism of this clash and allowed design of a mutation (CHIPD134A) that partially restores binding and turnover of pS416 tauC3. We find that pS416 is produced by the known AD-associated kinase, MARK2/Par-1b, providing a potential link to disease. In further support of this idea, an antibody against pS416 co-localizes with tauC3 in degenerative neurons within the hippocampus of AD patients. Together, these studies suggest a discrete molecular mechanism for how phosphorylation at a specific site contributes to accumulation of an important tau proteoform.
Collapse
Affiliation(s)
- Cory M Nadel
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158
- Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA 94158
| | - Kristin Wucherer
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158
| | - Abby Oehler
- Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA 94158
| | - Aye C Thwin
- Department of Biochemistry & Biophysics, University of California San Francisco, San Francisco, CA 94158
- Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA 94158
| | - Koli Basu
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158
| | - Matthew D Callahan
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158
- Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA 94158
| | - Daniel R Southworth
- Department of Biochemistry & Biophysics, University of California San Francisco, San Francisco, CA 94158
- Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA 94158
| | - Daniel A Mordes
- Department of Pathology, University of California San Francisco, San Francisco, CA 94158
- Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA 94158
| | - Charles S Craik
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158
| | - Jason E Gestwicki
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158
- Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA 94158
| |
Collapse
|
3
|
Abstract
Protein homeostasis relies on a balance between protein folding and protein degradation. Molecular chaperones like Hsp70 and Hsp90 fulfill well-defined roles in protein folding and conformational stability via ATP-dependent reaction cycles. These folding cycles are controlled by associations with a cohort of non-client protein co-chaperones, such as Hop, p23, and Aha1. Pro-folding co-chaperones facilitate the transit of the client protein through the chaperone-mediated folding process. However, chaperones are also involved in proteasomal and lysosomal degradation of client proteins. Like folding complexes, the ability of chaperones to mediate protein degradation is regulated by co-chaperones, such as the C-terminal Hsp70-binding protein (CHIP/STUB1). CHIP binds to Hsp70 and Hsp90 chaperones through its tetratricopeptide repeat (TPR) domain and functions as an E3 ubiquitin ligase using a modified RING finger domain (U-box). This unique combination of domains effectively allows CHIP to network chaperone complexes to the ubiquitin-proteasome and autophagosome-lysosome systems. This chapter reviews the current understanding of CHIP as a co-chaperone that switches Hsp70/Hsp90 chaperone complexes from protein folding to protein degradation.
Collapse
Affiliation(s)
- Abantika Chakraborty
- Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Makhanda/Grahamstown, South Africa
| | - Adrienne L Edkins
- Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Makhanda/Grahamstown, South Africa.
| |
Collapse
|
4
|
Umano A, Fang K, Qu Z, Scaglione JB, Altinok S, Treadway CJ, Wick ET, Paulakonis E, Karunanayake C, Chou S, Bardakjian TM, Gonzalez-Alegre P, Page RC, Schisler JC, Brown NG, Yan D, Scaglione KM. The molecular basis of spinocerebellar ataxia type 48 caused by a de novo mutation in the ubiquitin ligase CHIP. J Biol Chem 2022; 298:101899. [PMID: 35398354 PMCID: PMC9097460 DOI: 10.1016/j.jbc.2022.101899] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/24/2022] [Accepted: 03/28/2022] [Indexed: 11/25/2022] Open
Abstract
The spinocerebellar ataxias (SCAs) are a class of incurable diseases characterized by degeneration of the cerebellum that results in movement disorder. Recently, a new heritable form of SCA, spinocerebellar ataxia type 48 (SCA48), was attributed to dominant mutations in STIP1 homology and U box-containing 1 (STUB1); however, little is known about how these mutations cause SCA48. STUB1 encodes for the protein C terminus of Hsc70 interacting protein (CHIP), an E3 ubiquitin ligase. CHIP is known to regulate proteostasis by recruiting chaperones via a N-terminal tetratricopeptide repeat domain and recruiting E2 ubiquitin-conjugating enzymes via a C-terminal U-box domain. These interactions allow CHIP to mediate the ubiquitination of chaperone-bound, misfolded proteins to promote their degradation via the proteasome. Here we have identified a novel, de novo mutation in STUB1 in a patient with SCA48 encoding for an A52G point mutation in the tetratricopeptide repeat domain of CHIP. Utilizing an array of biophysical, biochemical, and cellular assays, we demonstrate that the CHIPA52G point mutant retains E3-ligase activity but has decreased affinity for chaperones. We further show that this mutant decreases cellular fitness in response to certain cellular stressors and induces neurodegeneration in a transgenic Caenorhabditis elegans model of SCA48. Together, our data identify the A52G mutant as a cause of SCA48 and provide molecular insight into how mutations in STUB1 cause SCA48.
Collapse
Affiliation(s)
- A Umano
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - K Fang
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - Z Qu
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - J B Scaglione
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - S Altinok
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - C J Treadway
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA; Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - E T Wick
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA; Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - E Paulakonis
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA; Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - C Karunanayake
- Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio, USA
| | - S Chou
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA; Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - T M Bardakjian
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - P Gonzalez-Alegre
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - R C Page
- Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio, USA
| | - J C Schisler
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - N G Brown
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA; Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - D Yan
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - K M Scaglione
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA; Department of Neurology, Duke University, Durham, North Carolina, USA; Duke Center for Neurodegeneration and Neurotherapeutics, Duke University, Durham, North Carolina, USA.
| |
Collapse
|
5
|
Kanack AJ, Olp MD, Newsom OJ, Scaglione JB, Gooden DM, McMahon K, Smith BC, Scaglione KM. Chemical Regulation of the Protein Quality Control E3 Ubiquitin Ligase C-Terminus of Hsc70 Interacting Protein (CHIP). Chembiochem 2022; 23:e202100633. [PMID: 35061295 PMCID: PMC9016715 DOI: 10.1002/cbic.202100633] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/20/2022] [Indexed: 11/09/2022]
Abstract
The ubiquitin ligase C-terminus of Hsc70 interacting protein (CHIP) is an important regulator of proteostasis. Despite playing an important role in maintaining proteostasis, little progress has been made in developing small molecules that regulate ubiquitin transfer by CHIP. Here we used differential scanning fluorimetry to identify compounds that bound CHIP. Compounds that bound CHIP were then analyzed by quantitative ubiquitination assays to identify those that altered CHIP function. One compound, MS.001, inhibited both the chaperone binding and ubiquitin ligase activity of CHIP at low micromolar concentrations. Interestingly, we found that MS.001 did not have activity against isolated U-box or tetratricopeptide (TPR) domains, but instead only inhibited full-length CHIP. Using in silico docking we identified a potential MS.001 binding site on the linker domain of CHIP and mutation of this site rendered CHIP resistant to MS.001. Together our data identify an inhibitor of the E3 ligase CHIP and provides insight into the development of compounds that regulate CHIP activity.
Collapse
Affiliation(s)
- Adam J Kanack
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Michael D Olp
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Oliver J Newsom
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Jamie B Scaglione
- Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA
| | - David M Gooden
- Department of Chemistry, SMSF Lab, Duke University, Durham, NC 27710, USA
| | - Kevin McMahon
- Department of Computational and Physical Sciences, Carroll University, Waukesha, WI 53186, USA
| | - Brian C Smith
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | | |
Collapse
|
6
|
The structure of an Hsp90-immunophilin complex reveals cochaperone recognition of the client maturation state. Mol Cell 2021; 81:3496-3508.e5. [PMID: 34380015 DOI: 10.1016/j.molcel.2021.07.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 05/18/2021] [Accepted: 07/19/2021] [Indexed: 11/23/2022]
Abstract
The Hsp90 chaperone promotes folding and activation of hundreds of client proteins in the cell through an ATP-dependent conformational cycle guided by distinct cochaperone regulators. The FKBP51 immunophilin binds Hsp90 with its tetratricopeptide repeat (TPR) domain and catalyzes peptidyl-prolyl isomerase (PPIase) activity during folding of kinases, nuclear receptors, and tau. Here we determined the cryoelectron microscopy (cryo-EM) structure of the human Hsp90:FKBP51:p23 complex to 3.3 Å, which, together with mutagenesis and crosslinking analyses, reveals the basis for cochaperone binding to Hsp90 during client maturation. A helix extension in the TPR functions as a key recognition element, interacting across the Hsp90 C-terminal dimer interface presented in the closed, ATP conformation. The PPIase domain is positioned along the middle domain, adjacent to Hsp90 client binding sites, whereas a single p23 makes stabilizing interactions with the N-terminal dimer. With this architecture, FKBP51 is positioned to act on specific client residues presented during Hsp90-catalyzed remodeling.
Collapse
|
7
|
Karunanayake C, Page RC. Cytosolic protein quality control machinery: Interactions of Hsp70 with a network of co-chaperones and substrates. Exp Biol Med (Maywood) 2021; 246:1419-1434. [PMID: 33730888 PMCID: PMC8243209 DOI: 10.1177/1535370221999812] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The chaperone heat shock protein 70 (Hsp70) and its network of co-chaperones serve as a central hub of cellular protein quality control mechanisms. Domain organization in Hsp70 dictates ATPase activity, ATP dependent allosteric regulation, client/substrate binding and release, and interactions with co-chaperones. The protein quality control activities of Hsp70 are classified as foldase, holdase, and disaggregase activities. Co-chaperones directly assisting protein refolding included J domain proteins and nucleotide exchange factors. However, co-chaperones can also be grouped and explored based on which domain of Hsp70 they interact. Here we discuss how the network of cytosolic co-chaperones for Hsp70 contributes to the functions of Hsp70 while closely looking at their structural features. Comparison of domain organization and the structures of co-chaperones enables greater understanding of the interactions, mechanisms of action, and roles played in protein quality control.
Collapse
Affiliation(s)
| | - Richard C Page
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| |
Collapse
|
8
|
Dicarbonyl stress, protein glycation and the unfolded protein response. Glycoconj J 2021; 38:331-340. [PMID: 33644826 PMCID: PMC8116241 DOI: 10.1007/s10719-021-09980-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 01/26/2021] [Accepted: 02/10/2021] [Indexed: 12/22/2022]
Abstract
The reactive dicarbonyl metabolite, methylglyoxal (MG), is increased in obesity and diabetes and is implicated in the development of insulin resistance, type 2 diabetes mellitus and vascular complications of diabetes. Dicarbonyl stress is the metabolic state of abnormal high MG concentration. MG is an arginine-directed glycating agent and precursor of the major advanced glycation endproduct, arginine-derived hydroimidazolone MG-H1. MG-H1 is often formed on protein surfaces and an uncharged hydrophobic residue, inducing protein structural distortion and misfolding. Recent studies indicate that dicarbonyl stress in human endothelial cells and fibroblasts in vitro induced a proteomic response consistent with activation of the unfolded protein response (UPR). The response included: increased abundance of heat shock proteins and ubiquitin ligases catalysing the removal of proteins with unshielded surface hydrophobic patches and formation of polyubiquitinated chains to encapsulate misfolded proteins; and increased low grade inflammation. Activation of the UPR is implicated in insulin resistance. An effective strategy to counter increased MG is inducing increased expression of glyoxalase-1 (Glo1). An optimized inducer of Glo1 expression, trans-resveratrol and hesperetin combination, normalized increased MG concentration, corrected insulin resistance and decreased low grade inflammation in overweight and obese subjects. We propose that dicarbonyl stress, through increased formation of MG-glycated proteins, may be an important physiological stimulus of the UPR and Glo1 inducers may provide a route to effective suppression and therapy. With further investigation and validation, this may provide key new insight into physiological activators of the UPR and association with dicarbonyl stress.
Collapse
|
9
|
Gonçalves CDC, Pinheiro GMS, Dahlström KM, Souto DEP, Kubota LT, Barbosa LRS, Ramos CHI. On the structure and function of Sorghum bicolor CHIP (carboxyl terminus of Hsc70-interacting protein): A link between chaperone and proteasome systems. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 296:110506. [PMID: 32540021 DOI: 10.1016/j.plantsci.2020.110506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 04/12/2020] [Accepted: 04/18/2020] [Indexed: 06/11/2023]
Abstract
The co-chaperone CHIP (carboxy terminus of Hsc70 interacting protein) is very important for many cell activities since it regulates the ubiquitination of substrates targeted for proteasomal degradation. However, information on the structure-function relationship of CHIP from plants and how it interacts and ubiquitinates other plant chaperones is still needed. For that, the CHIP ortholog from Sorghum bicolor (SbCHIP) was identified and studied in detail. SbCHIP was purified and produced folded and pure, being capable of keeping its structural conformation up to 42 °C, indicating that cellular function is maintained even in a hot environment. Also, SbCHIP was able to bind plant Hsp70 and Hsp90 with high affinity and interact with E2 enzymes, performing E3 ligase activity. The data allowed to reveal the pattern of plant Hsp70 and Hsp90 ubiquitination and described which plant E2 enzymes are likely involved in SbCHIP-mediated ubiquitination. Aditionally, we obtained information on the SbCHIP conformation, showing that it is a non-globular symmetric dimer and allowing to put forward a model for the interaction of SbCHIP with chaperones and E2 enzymes that suggests a mechanism of ubiquitination. Altogether, the results presented here are useful additions to the study of protein folding and degradation in plants.
Collapse
Affiliation(s)
| | - Glaucia M S Pinheiro
- Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP 13083-970, Brazil
| | - Käthe M Dahlström
- Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP 13083-970, Brazil
| | - Dênio E P Souto
- Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP 13083-970, Brazil
| | - Lauro T Kubota
- Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP 13083-970, Brazil
| | - Leandro R S Barbosa
- Institute of Physics, University of São Paulo-USP, São Paulo, SP 05508-090, Brazil
| | - Carlos H I Ramos
- Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP 13083-970, Brazil.
| |
Collapse
|
10
|
Kanack A, Vittal V, Haver H, Keppel T, Gundry RL, Klevit RE, Scaglione KM. UbcH5 Interacts with Substrates to Participate in Lysine Selection with the E3 Ubiquitin Ligase CHIP. Biochemistry 2020; 59:2078-2088. [PMID: 32401531 DOI: 10.1021/acs.biochem.0c00084] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The E3 ubiquitin ligase C-terminus of Hsc70 interacting protein (CHIP) plays a critical role in regulating the ubiquitin-dependent degradation of misfolded proteins. CHIP mediates the ubiquitination of the α-amino-terminus of substrates with the E2 Ube2w and facilitates the ubiquitination of lysine residues with the E2 UbcH5. While it is known that Ube2w directly interacts with the disordered regions at the N-terminus of its substrates, it is unclear how CHIP and UbcH5 mediate substrate lysine selection. Here, we have decoupled the contributions of the E2, UbcH5, and the E3, CHIP, in ubiquitin transfer. We show that UbcH5 selects substrate lysine residues independent of CHIP, and that CHIP participates in lysine selection by fine-tuning the subset of substrate lysines that are ubiquitinated. We also identify lysine 128 near the C-terminus of UbcH5 as a critical residue for the efficient ubiquitin transfer by UbcH5 in both the presence and absence of CHIP. Together, these data demonstrate an important role of the UbcH5/substrate interactions in mediating the efficient ubiquitin transfer by the CHIP/UbcH5 complex.
Collapse
Affiliation(s)
- Adam Kanack
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, United States.,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, United States
| | - Vinayak Vittal
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, United States
| | - Holly Haver
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina 27710, United States
| | - Theodore Keppel
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, United States
| | - Rebekah L Gundry
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, United States
| | - Rachel E Klevit
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, United States
| | - Kenneth Matthew Scaglione
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, United States.,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, United States.,Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina 27710, United States.,Department of Neurology, Duke University, Durham, North Carolina 27710, United States.,Duke Center for Neurodegeneration and Neurotherapeutics, Duke University, Durham, North Carolina 27710, United States
| |
Collapse
|
11
|
Rinaldi L, Delle Donne R, Catalanotti B, Torres-Quesada O, Enzler F, Moraca F, Nisticò R, Chiuso F, Piccinin S, Bachmann V, Lindner HH, Garbi C, Scorziello A, Russo NA, Synofzik M, Stelzl U, Annunziato L, Stefan E, Feliciello A. Feedback inhibition of cAMP effector signaling by a chaperone-assisted ubiquitin system. Nat Commun 2019; 10:2572. [PMID: 31189917 PMCID: PMC6561907 DOI: 10.1038/s41467-019-10037-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 04/12/2019] [Indexed: 02/07/2023] Open
Abstract
Activation of G-protein coupled receptors elevates cAMP levels promoting dissociation of protein kinase A (PKA) holoenzymes and release of catalytic subunits (PKAc). This results in PKAc-mediated phosphorylation of compartmentalized substrates that control central aspects of cell physiology. The mechanism of PKAc activation and signaling have been largely characterized. However, the modes of PKAc inactivation by regulated proteolysis were unknown. Here, we identify a regulatory mechanism that precisely tunes PKAc stability and downstream signaling. Following agonist stimulation, the recruitment of the chaperone-bound E3 ligase CHIP promotes ubiquitylation and proteolysis of PKAc, thus attenuating cAMP signaling. Genetic inactivation of CHIP or pharmacological inhibition of HSP70 enhances PKAc signaling and sustains hippocampal long-term potentiation. Interestingly, primary fibroblasts from autosomal recessive spinocerebellar ataxia 16 (SCAR16) patients carrying germline inactivating mutations of CHIP show a dramatic dysregulation of PKA signaling. This suggests the existence of a negative feedback mechanism for restricting hormonally controlled PKA activities.
Collapse
Affiliation(s)
- Laura Rinaldi
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131, Naples, Italy
| | - Rossella Delle Donne
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131, Naples, Italy
| | - Bruno Catalanotti
- Department of Pharmacy, University Federico II, 80131, Naples, Italy
| | - Omar Torres-Quesada
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020, Innsbruck, Austria
| | - Florian Enzler
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020, Innsbruck, Austria
| | - Federica Moraca
- Department of Chemical Sciences, University Federico II, 80131, Naples, Italy
| | - Robert Nisticò
- European Brain Research Institute, Rita Levi-Montalcini Foundation and Department of Biology, University Tor Vergata, 00143, Rome, Italy
| | - Francesco Chiuso
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131, Naples, Italy
| | - Sonia Piccinin
- European Brain Research Institute, Rita Levi-Montalcini Foundation and Department of Biology, University Tor Vergata, 00143, Rome, Italy
| | - Verena Bachmann
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020, Innsbruck, Austria
| | - Herbert H Lindner
- Division of Clinical Biochemistry, Biocenter Medical University of Innsbruck, Innrain 80-82, A-6020, Innsbruck, Austria
| | - Corrado Garbi
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131, Naples, Italy
| | - Antonella Scorziello
- Department of Neuroscience, Reproductive and Odontostomatological Sciences, University Federico II, 80131, Naples, Italy
| | | | - Matthis Synofzik
- Department of Neurodegeneration, Hertie Institute for Clinical Brain Research (HIH), University of Tübingen and German Center for Neurodegenerative Diseases (DZNE), 72076, Tübingen, Germany
| | - Ulrich Stelzl
- Institute of Pharmaceutical Sciences, University of Graz and BioTechMed-Graz, 8010, Graz, Austria
| | | | - Eduard Stefan
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020, Innsbruck, Austria
| | - Antonio Feliciello
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131, Naples, Italy.
| |
Collapse
|
12
|
Fang CT, Kuo HH, Hsu SC, Yih LH. HSP70 is required for the proper assembly of pericentriolar material and function of mitotic centrosomes. Cell Div 2019; 14:4. [PMID: 31110557 PMCID: PMC6511203 DOI: 10.1186/s13008-019-0047-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 04/30/2019] [Indexed: 12/03/2022] Open
Abstract
Background At the onset of mitosis, the centrosome expands and matures, acquiring enhanced activities for microtubule nucleation and assembly of a functional bipolar mitotic spindle. However, the mechanisms that regulate centrosome expansion and maturation are largely unknown. Previously, we demonstrated in an immortalized human cell line CGL2 and cancer cell line HeLa that the inducible form of heat shock protein 70 (HSP70) accumulates at the mitotic centrosome and is required for centrosome maturation and bipolar spindle assembly. Results In this study, we further show that HSP70 accumulated at the spindle pole in a PLK1-dependent manner. HSP70 colocalized with pericentrin (PCNT), CEP215 and γ-tubulin at the spindle pole and was required for the 3D assembly of these three proteins, which supports mitotic centrosome function. Loss of HSP70 disrupted mitotic centrosome structure, reduced pericentriolar material recruitment and induced fragmentation of spindle poles. In addition, HSP70 was necessary for the interaction between PCNT and CEP215 and also facilitated PLK1 accumulation and function at the spindle pole. Furthermore, we found that HSP70 chaperone activity is required for PCNT accumulation at the mitotic centrosome and assembly of mitotic spindles. Conclusion Our current results demonstrate that HSP70 is required for the accurate assembly of the pericentriolar material and proper functioning of mitotic centrosomes.
Collapse
Affiliation(s)
- Chieh-Ting Fang
- 1Department of Life Science, National Taiwan University, Taipei, Taiwan.,2Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Hsiao-Hui Kuo
- 2Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Shao-Chun Hsu
- 2Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Ling-Huei Yih
- 2Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| |
Collapse
|
13
|
Quintana-Gallardo L, Martín-Benito J, Marcilla M, Espadas G, Sabidó E, Valpuesta JM. The cochaperone CHIP marks Hsp70- and Hsp90-bound substrates for degradation through a very flexible mechanism. Sci Rep 2019; 9:5102. [PMID: 30911017 PMCID: PMC6433865 DOI: 10.1038/s41598-019-41060-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 01/22/2019] [Indexed: 11/26/2022] Open
Abstract
Some molecular chaperones are involved not only in assisting the folding of proteins but also, given appropriate conditions, in their degradation. This is the case for Hsp70 and Hsp90 which, in concert with the cochaperone CHIP, direct their bound substrate to degradation through ubiquitination. We generated complexes between the chaperones (Hsp70 or Hsp90), the cochaperone CHIP and, as substrate, a p53 variant containing the GST protein (p53-TMGST). Both ternary complexes (Hsp70:p53-TMGST:CHIP and Hsp90:p53-TMGST:CHIP) ubiquitinated the substrate at a higher efficiency than in the absence of the chaperones. The 3D structures of the two complexes, obtained using a combination of cryoelectron microscopy and crosslinking mass spectrometry, showed the substrate located between the chaperone and the cochaperone, suggesting a ubiquitination mechanism in which the chaperone-bound substrate is presented to CHIP. These complexes are inherently flexible, which is important for the ubiquitination process.
Collapse
Affiliation(s)
| | | | - Miguel Marcilla
- Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049, Madrid, Spain
| | - Guadalupe Espadas
- Proteomics Unit, Centre de Regulació Genòmica (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Proteomics Unit, Universitat Pompeu Fabra, Barcelona, Spain
| | - Eduard Sabidó
- Proteomics Unit, Centre de Regulació Genòmica (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Proteomics Unit, Universitat Pompeu Fabra, Barcelona, Spain
| | | |
Collapse
|
14
|
Ouimet CM, Dawod M, Grinias J, Assimon VA, Lodge J, Mapp AK, Gestwicki JE, Kennedy RT. Protein cross-linking capillary electrophoresis at increased throughput for a range of protein-protein interactions. Analyst 2019; 143:1805-1812. [PMID: 29565056 DOI: 10.1039/c7an02098h] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tools for measuring affinities and stoichiometries of protein-protein complexes are valuable for elucidating the role of protein-protein interactions (PPIs) in governing cell functions and screening for PPI modulators. Such measurements can be challenging because PPIs can span a wide range of affinities and include stoichiometries from dimers to high order oligomers. Also, most techniques require large amounts of protein which can hamper research for difficult to obtain proteins. Protein cross-linking capillary electrophoresis (PXCE) has the potential to directly measure PPIs and even resolve multiple PPIs while consuming attomole quantities. Previously PXCE has only been used for high affinity, 1 : 1 complexes; here we expand the utility of PXCE to access a wide range of PPIs including weak and multimeric oligomers. Use of glutaraldehyde as the cross-linking agent was key to advancing the method because of its rapid reaction kinetics. A 10 s reaction time was found to be sufficient for cross-linking and quantification of seven different PPIs with Kd values ranging from low μM to low nM including heat shock protein 70 (Hsp70) interacting with heat shock organizing protein (3.8 ± 0.7 μM) and bcl2 associated anthanogene (26 ± 6 nM). Non-specific cross-linking of protein aggregates was found to be minimal at protein concentrations <20 μM as assessed by size exclusion chromatography. PXCE was sensitive enough to measure changes in PPI affinity induced by the protein nucleotide state or point mutations in the protein-binding site. Further, several interactions could be resolved in a single run, including Hsp70 monomer, homodimer and Hsp70 complexed the with c-terminus of Hsp70 interacting protein (CHIP). Finally, the throughput of PXCE was increased to 1 min per sample suggesting potential for utility in screening.
Collapse
Affiliation(s)
- Claire M Ouimet
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Mohamed Dawod
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
| | - James Grinias
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA. and Department of Chemistry, Rowan University, Glassboro, NJ 08028, USA
| | - Victoria A Assimon
- Department of Pharmaceutical Chemistry, University of California at San Francisco, California 94158, USA
| | - Jean Lodge
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Anna K Mapp
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA. and Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jason E Gestwicki
- Department of Pharmaceutical Chemistry, University of California at San Francisco, California 94158, USA
| | - Robert T Kennedy
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA. and Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| |
Collapse
|
15
|
Taylor IR, Ahmad A, Wu T, Nordhues BA, Bhullar A, Gestwicki JE, Zuiderweg ERP. The disorderly conduct of Hsc70 and its interaction with the Alzheimer's-related Tau protein. J Biol Chem 2018; 293:10796-10809. [PMID: 29764935 DOI: 10.1074/jbc.ra118.002234] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/10/2018] [Indexed: 01/10/2023] Open
Abstract
Hsp70 chaperones bind to various protein substrates for folding, trafficking, and degradation. Considerable structural information is available about how prokaryotic Hsp70 (DnaK) binds substrates, but less is known about mammalian Hsp70s, of which there are 13 isoforms encoded in the human genome. Here, we report the interaction between the human Hsp70 isoform heat shock cognate 71-kDa protein (Hsc70 or HSPA8) and peptides derived from the microtubule-associated protein Tau, which is linked to Alzheimer's disease. For structural studies, we used an Hsc70 construct (called BETA) comprising the substrate-binding domain but lacking the lid. Importantly, we found that truncating the lid does not significantly impair Hsc70's chaperone activity or allostery in vitro Using NMR, we show that BETA is partially dynamically disordered in the absence of substrate and that binding of the Tau sequence GKVQIINKKG (with a KD = 500 nm) causes dramatic rigidification of BETA. NOE distance measurements revealed that Tau binds to the canonical substrate-binding cleft, similar to the binding observed with DnaK. To further develop BETA as a tool for studying Hsc70 interactions, we also measured BETA binding in NMR and fluorescent competition assays to peptides derived from huntingtin, insulin, a second Tau-recognition sequence, and a KFERQ-like sequence linked to chaperone-mediated autophagy. We found that the insulin C-peptide binds BETA with high affinity (KD < 100 nm), whereas the others do not (KD > 100 μm). Together, our findings reveal several similarities and differences in how prokaryotic and mammalian Hsp70 isoforms interact with different substrate peptides.
Collapse
Affiliation(s)
- Isabelle R Taylor
- the Institute for Neurodegenerative Disease, University of California at San Francisco, San Francisco, California 94158, and
| | - Atta Ahmad
- From the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Taia Wu
- the Institute for Neurodegenerative Disease, University of California at San Francisco, San Francisco, California 94158, and
| | - Bryce A Nordhues
- the Department of Molecular Medicine and Byrd Alzheimer's Institute, University of South Florida, Tampa, Florida 33613
| | - Anup Bhullar
- From the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Jason E Gestwicki
- the Institute for Neurodegenerative Disease, University of California at San Francisco, San Francisco, California 94158, and
| | - Erik R P Zuiderweg
- From the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109,
| |
Collapse
|
16
|
Freilich R, Arhar T, Abrams JL, Gestwicki JE. Protein-Protein Interactions in the Molecular Chaperone Network. Acc Chem Res 2018; 51:940-949. [PMID: 29613769 DOI: 10.1021/acs.accounts.8b00036] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Molecular chaperones play a central role in protein homeostasis (a.k.a. proteostasis) by balancing protein folding, quality control, and turnover. To perform these diverse tasks, chaperones need the malleability to bind nearly any "client" protein and the fidelity to detect when it is misfolded. Remarkably, these activities are carried out by only ∼180 dedicated chaperones in humans. How do a relatively small number of chaperones maintain cellular and organismal proteostasis for an entire proteome? Furthermore, once a chaperone binds a client, how does it "decide" what to do with it? One clue comes from observations that individual chaperones engage in protein-protein interactions (PPIs)-both with each other and with their clients. These physical links coordinate multiple chaperones into organized, functional complexes and facilitate the "handoff" of clients between them. PPIs also link chaperones and their clients to other cellular pathways, such as those that mediate trafficking (e.g., cytoskeleton) and degradation (e.g., proteasome). The PPIs of the chaperone network have a wide range of affinity values (nanomolar to micromolar) and involve many distinct types of domain modules, such as J domains, zinc fingers, and tetratricopeptide repeats. Many of these motifs have the same binding surfaces on shared partners, such that members of one chaperone class often compete for the same interactions. Somehow, this collection of PPIs draws together chaperone families and creates multiprotein subnetworks that are able to make the "decisions" of protein quality control. The key to understanding chaperone-mediated proteostasis might be to understand how PPIs are regulated. This Account will discuss the efforts of our group and others to map, measure, and chemically perturb the PPIs within the molecular chaperone network. Structural biology methods, including X-ray crystallography, NMR spectroscopy, and electron microscopy, have all played important roles in visualizing the chaperone PPIs. Guided by these efforts and -omics approaches to measure PPIs, new advances in high-throughput chemical screening that are specially designed to account for the challenges of this system have emerged. Indeed, chemical biology has played a particularly important role in this effort, as molecules that either promote or inhibit specific PPIs have proven to be invaluable research probes in cells and animals. In addition, these molecules have provided leads for the potential treatment of protein misfolding diseases. One of the major products of this research field has been the identification of putative PPI drug targets within the chaperone network, which might be used to change chaperone "decisions" and rebalance proteostasis.
Collapse
Affiliation(s)
- Rebecca Freilich
- Department of Pharmaceutical Chemistry and The Institute for Neurodegenerative Disease, University of California—San Francisco, San Francisco, California 94158, United States
| | - Taylor Arhar
- Department of Pharmaceutical Chemistry and The Institute for Neurodegenerative Disease, University of California—San Francisco, San Francisco, California 94158, United States
| | - Jennifer L. Abrams
- Department of Pharmaceutical Chemistry and The Institute for Neurodegenerative Disease, University of California—San Francisco, San Francisco, California 94158, United States
| | - Jason E. Gestwicki
- Department of Pharmaceutical Chemistry and The Institute for Neurodegenerative Disease, University of California—San Francisco, San Francisco, California 94158, United States
| |
Collapse
|
17
|
Kanack AJ, Newsom OJ, Scaglione KM. Most mutations that cause spinocerebellar ataxia autosomal recessive type 16 (SCAR16) destabilize the protein quality-control E3 ligase CHIP. J Biol Chem 2018; 293:2735-2743. [PMID: 29317501 DOI: 10.1074/jbc.ra117.000477] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 01/03/2018] [Indexed: 01/13/2023] Open
Abstract
The accumulation of misfolded proteins promotes protein aggregation and neuronal death in many neurodegenerative diseases. To counteract misfolded protein accumulation, neurons have pathways that recognize and refold or degrade aggregation-prone proteins. One U-box-containing E3 ligase, C terminus of Hsc70-interacting protein (CHIP), plays a key role in this process, targeting misfolded proteins for proteasomal degradation. CHIP plays a protective role in mouse models of neurodegenerative disease, and in humans, mutations in CHIP cause spinocerebellar ataxia autosomal recessive type 16 (SCAR16), a fatal neurodegenerative disease characterized by truncal and limb ataxia that results in gait instability. Here, we systematically analyzed CHIP mutations that cause SCAR16 and found that most SCAR16 mutations destabilize CHIP. This destabilization caused mutation-specific defects in CHIP activity, including increased formation of soluble oligomers, decreased interactions with chaperones, diminished substrate ubiquitination, and reduced steady-state levels in cells. Consistent with decreased CHIP stability promoting its dysfunction in SCAR16, most mutant proteins recovered activity when the assays were performed below the mutants' melting temperature. Together, our results have uncovered the molecular basis of genetic defects in CHIP function that cause SCAR16. Our insights suggest that compounds that improve the thermostability of genetic CHIP variants may be beneficial for treating patients with SCAR16.
Collapse
Affiliation(s)
- Adam J Kanack
- Department of Biochemistry and the Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Oliver J Newsom
- Department of Biochemistry and the Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Kenneth Matthew Scaglione
- Department of Biochemistry and the Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226.
| |
Collapse
|
18
|
Mot AC, Prell E, Klecker M, Naumann C, Faden F, Westermann B, Dissmeyer N. Real-time detection of N-end rule-mediated ubiquitination via fluorescently labeled substrate probes. THE NEW PHYTOLOGIST 2018; 217:613-624. [PMID: 28277608 PMCID: PMC5763331 DOI: 10.1111/nph.14497] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 01/26/2017] [Indexed: 05/18/2023]
Abstract
The N-end rule pathway has emerged as a major system for regulating protein functions by controlling their turnover in medical, animal and plant sciences as well as agriculture. Although novel functions and enzymes of the pathway have been discovered, the ubiquitination mechanism and substrate specificity of N-end rule pathway E3 ubiquitin ligases have remained elusive. Taking the first discovered bona fide plant N-end rule E3 ligase PROTEOLYSIS1 (PRT1) as a model, we used a novel tool to molecularly characterize polyubiquitination live, in real time. We gained mechanistic insights into PRT1 substrate preference and activation by monitoring live ubiquitination using a fluorescent chemical probe coupled to artificial substrate reporters. Ubiquitination was measured by rapid in-gel fluorescence scanning as well as in real time by fluorescence polarization. The enzymatic activity, substrate specificity, mechanisms and reaction optimization of PRT1-mediated ubiquitination were investigated ad hoc instantaneously and with significantly reduced reagent consumption. We demonstrated that PRT1 is indeed an E3 ligase, which has been hypothesized for over two decades. These results demonstrate that PRT1 has the potential to be involved in polyubiquitination of various substrates and therefore pave the way to understanding recently discovered phenotypes of prt1 mutants.
Collapse
Affiliation(s)
- Augustin C. Mot
- Independent Junior Research Group on Protein Recognition and DegradationLeibniz Institute of Plant Biochemistry (IPB)Weinberg 3Halle (Saale)D‐06120Germany
- ScienceCampus Halle – Plant‐based BioeconomyBetty‐Heimann‐Str. 3Halle (Saale)D‐06120Germany
| | - Erik Prell
- Department of Bioorganic ChemistryLeibniz Institute of Plant Biochemistry (IPB)Weinberg 3Halle (Saale)D‐06120Germany
| | - Maria Klecker
- Independent Junior Research Group on Protein Recognition and DegradationLeibniz Institute of Plant Biochemistry (IPB)Weinberg 3Halle (Saale)D‐06120Germany
- ScienceCampus Halle – Plant‐based BioeconomyBetty‐Heimann‐Str. 3Halle (Saale)D‐06120Germany
| | - Christin Naumann
- Independent Junior Research Group on Protein Recognition and DegradationLeibniz Institute of Plant Biochemistry (IPB)Weinberg 3Halle (Saale)D‐06120Germany
- ScienceCampus Halle – Plant‐based BioeconomyBetty‐Heimann‐Str. 3Halle (Saale)D‐06120Germany
| | - Frederik Faden
- Independent Junior Research Group on Protein Recognition and DegradationLeibniz Institute of Plant Biochemistry (IPB)Weinberg 3Halle (Saale)D‐06120Germany
- ScienceCampus Halle – Plant‐based BioeconomyBetty‐Heimann‐Str. 3Halle (Saale)D‐06120Germany
| | - Bernhard Westermann
- Department of Bioorganic ChemistryLeibniz Institute of Plant Biochemistry (IPB)Weinberg 3Halle (Saale)D‐06120Germany
| | - Nico Dissmeyer
- Independent Junior Research Group on Protein Recognition and DegradationLeibniz Institute of Plant Biochemistry (IPB)Weinberg 3Halle (Saale)D‐06120Germany
- ScienceCampus Halle – Plant‐based BioeconomyBetty‐Heimann‐Str. 3Halle (Saale)D‐06120Germany
| |
Collapse
|
19
|
Morey TM, Winick-Ng W, Seah C, Rylett RJ. Chaperone-Mediated Regulation of Choline Acetyltransferase Protein Stability and Activity by HSC/HSP70, HSP90, and p97/VCP. Front Mol Neurosci 2017; 10:415. [PMID: 29311808 PMCID: PMC5733026 DOI: 10.3389/fnmol.2017.00415] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/30/2017] [Indexed: 11/13/2022] Open
Abstract
Choline acetyltransferase (ChAT) synthesizes the neurotransmitter acetylcholine in cholinergic neurons, and mutations of this enzyme are linked to the neuromuscular disorder congenital myasthenic syndrome (CMS). One CMS-related mutation, V18M, reduces ChAT enzyme activity and cellular protein levels, and is located within a highly-conserved N-terminal proline-rich motif at residues 14PKLPVPP20. We showed previously that disruption of this proline-rich motif by either proline-to-alanine mutation (P17A/P19A) or mutation of residue Val18 (V18M) enhances ubiquitination and degradation of these mutant ChAT proteins expressed in cholinergic SN56 cells by an unknown mechanism. In this study, using proximity-dependent biotin identification (BioID), co-immunoprecipitation and in situ proximity-ligation assay (PLA), we identified the heat shock proteins (HSPs) HSC/HSP70 and HSP90 as novel ChAT protein-interactors. These molecular chaperones are well-known for promoting the folding and stabilization of cellular proteins. Thus, we found that inhibition of HSPs by treatment of cells with either the HSC/HSP70 inhibitors 2-phenylethynesulfonamide (PES) or VER-155008, or the HSP90 inhibitor 17-AAG reduced cellular ChAT activity and solubility, and enhanced the ubiquitination and proteasome-dependent loss of ChAT protein. Importantly, the effects of HSP inhibition were greater for mutant ChAT proteins (P17A/P19A-ChAT and CMS-related V18M- and A513T-ChAT) compared to wild-type ChAT. HSPs can promote ubiquitination and degradation of terminally misfolded proteins through cooperative interaction with the E3 ubiquitin ligase CHIP/Stub1, and while we show that ChAT interacts with CHIP in situ, siRNA-mediated knock-down of CHIP had no effect on either wild-type or mutant ChAT protein levels. However, inhibition of the endoplasmic reticulum (ER)- and HSP-associated co-chaperone p97/VCP prevented degradation of ubiquitinated ChAT. Together, these results identify novel mechanisms for the functional regulation of wild-type and CMS-related mutant ChAT by pro-stabilizing HSPs and the pro-degradative co-chaperone p97/VCP that may have broader implications for ChAT function during cellular stress and disease.
Collapse
Affiliation(s)
- Trevor M Morey
- Molecular Medicine Research Laboratories, Robarts Research Institute, University of Western Ontario, London, ON, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Warren Winick-Ng
- Molecular Medicine Research Laboratories, Robarts Research Institute, University of Western Ontario, London, ON, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada.,Epigenetic Regulation and Chromatin Architecture Group, Berlin Institute for Medical Systems Biology, Max-Delbrück Centre for Molecular Medicine, Berlin, Germany
| | - Claudia Seah
- Molecular Medicine Research Laboratories, Robarts Research Institute, University of Western Ontario, London, ON, Canada
| | - R Jane Rylett
- Molecular Medicine Research Laboratories, Robarts Research Institute, University of Western Ontario, London, ON, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| |
Collapse
|
20
|
Wang Y, Lee S, Ha Y, Lam W, Chen SR, Dutschman GE, Gullen EA, Grill SP, Cheng Y, Fürstner A, Francis S, Baker DC, Yang X, Lee KH, Cheng YC. Tylophorine Analogs Allosterically Regulates Heat Shock Cognate Protein 70 And Inhibits Hepatitis C Virus Replication. Sci Rep 2017; 7:10037. [PMID: 28855547 PMCID: PMC5577180 DOI: 10.1038/s41598-017-08815-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 07/19/2017] [Indexed: 12/12/2022] Open
Abstract
Tylophorine analogs have been shown to exhibit diverse activities against cancer, inflammation, arthritis, and lupus in vivo. In this study, we demonstrated that two tylophorine analogs, DCB-3503 and rac-cryptopleurine, exhibit potent inhibitory activity against hepatitis C virus (HCV) replication in genotype 1b Con 1 isolate. The inhibition of HCV replication is at least partially mediated through cellular heat shock cognate protein 70 (Hsc70). Hsc70 associates with the HCV replication complex by primarily binding to the poly U/UC motifs in HCV RNA. The interaction of DCB-3503 and rac-cryptopleurine with Hsc70 promotes the ATP hydrolysis activity of Hsc70 in the presence of the 3' poly U/UC motif of HCV RNA. Regulating the ATPase activity of Hsc70 may be one of the mechanisms by which tylophorine analogs inhibit HCV replication. This study demonstrates the novel anti-HCV activity of tylophorine analogs. Our results also highlight the importance of Hsc70 in HCV replication.
Collapse
Affiliation(s)
- Ying Wang
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA. .,Institute of Chinese Medical Sciences and State Key Laboratory of Quality Research in Chinese Medicine, University of Macau, Macau, SAR, China.
| | - Sangwon Lee
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Ya Ha
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Wing Lam
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Shao-Ru Chen
- Institute of Chinese Medical Sciences and State Key Laboratory of Quality Research in Chinese Medicine, University of Macau, Macau, SAR, China
| | - Ginger E Dutschman
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Elizabeth A Gullen
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Susan P Grill
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Yao Cheng
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Samson Francis
- Department of Chemistry, The University of Tennessee, Knoxville, TN, 37996, USA
| | - David C Baker
- Department of Chemistry, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Xiaoming Yang
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Kuo-Hsiung Lee
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, 27599, USA.,Chinese Medicine Research and Development Center, China Medical University and Hospital, Taichung, Taiwan
| | - Yung-Chi Cheng
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA.
| |
Collapse
|
21
|
Zuiderweg ERP, Gestwicki JE. Backbone and methyl resonance assignments of the 42 kDa human Hsc70 nucleotide binding domain in the ADP state. BIOMOLECULAR NMR ASSIGNMENTS 2017; 11:11-15. [PMID: 27699616 PMCID: PMC5344757 DOI: 10.1007/s12104-016-9711-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 09/29/2016] [Indexed: 06/06/2023]
Abstract
Hsc70 is the constitutively expressed mammalian heat shock 70 kDa (Hsp70) cytosolic chaperone. It plays a central role in cellular proteostasis and protein trafficking. Here, we present the backbone and methyl group assignments for the 386-residue nucleotide binding domain of the human protein. This domain controls the chaperone's allostery, binds multiple co-chaperones and is the target of several classes of known chemical Hsp70 inhibitors. The NMR assignments are based on common triple resonance experiments with triple labeled protein, and on several 15N and 13C-resolved 3D NOE experiments with methyl-reprotonated samples. A combination of computer and manual data interpretation was used.
Collapse
Affiliation(s)
- Erik R P Zuiderweg
- Department of Biological Chemistry, The University of Michigan Medical School, 1500 Medical Center Drive, Ann Arbor, MI, 48109, USA.
| | - Jason E Gestwicki
- Institute for Neurodegenerative Disease, University of California at San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| |
Collapse
|
22
|
Zuiderweg ERP, Hightower LE, Gestwicki JE. The remarkable multivalency of the Hsp70 chaperones. Cell Stress Chaperones 2017; 22:173-189. [PMID: 28220454 PMCID: PMC5352603 DOI: 10.1007/s12192-017-0776-y] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 02/07/2017] [Indexed: 01/01/2023] Open
Abstract
Hsp70 proteins are key to maintaining intracellular protein homeostasis. To carry out this task, they employ a large number of cochaperones and adapter proteins. Here, we review what is known about the interaction between the chaperones and partners, with a strong slant toward structural biology. Hsp70s in general, and Hsc70 (HSPA8) in particular, display an amazing array of interfaces with their protein cofactors. We also review the known interactions between Hsp70s with lipids and with active compounds that may become leads toward Hsp70 modulation for treatment of a variety of diseases.
Collapse
Affiliation(s)
- Erik R P Zuiderweg
- Department of Biological Chemistry, The University of Michigan Medical School, 1500 Medical Center Drive, Ann Arbor, MI, 48109, USA.
| | - Lawrence E Hightower
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, 06269, USA
| | - Jason E Gestwicki
- Institute for Neurodegenerative Disease, University of California at San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| |
Collapse
|
23
|
VanPelt J, Page RC. Unraveling the CHIP:Hsp70 complex as an information processor for protein quality control. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1865:133-141. [PMID: 27863257 DOI: 10.1016/j.bbapap.2016.11.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 11/11/2016] [Accepted: 11/14/2016] [Indexed: 11/24/2022]
Abstract
The CHIP:Hsp70 complex stands at the crossroads of the cellular protein quality control system. Hsp70 facilitates active refolding of misfolded client proteins, while CHIP directs ubiquitination of misfolded client proteins bound to Hsp70. The direct competition between CHIP and Hsp70 for the fate of misfolded proteins leads to the question: how does the CHIP:Hsp70 complex execute triage decisions that direct misfolded proteins for either refolding or degradation? The current body of literature points toward action of the CHIP:Hsp70 complex as an information processor that takes inputs in the form of client folding state, dynamics, and posttranslational modifications, then outputs either refolded or ubiquitinated client proteins. Herein we examine the CHIP:Hsp70 complex beginning with the structure and function of CHIP and Hsp70, followed by an examination of recent studies of the interactions and dynamics of the CHIP:Hsp70 complex.
Collapse
Affiliation(s)
- Jamie VanPelt
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Richard C Page
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| |
Collapse
|
24
|
Kathage B, Gehlert S, Ulbricht A, Lüdecke L, Tapia VE, Orfanos Z, Wenzel D, Bloch W, Volkmer R, Fleischmann BK, Fürst DO, Höhfeld J. The cochaperone BAG3 coordinates protein synthesis and autophagy under mechanical strain through spatial regulation of mTORC1. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:62-75. [PMID: 27756573 DOI: 10.1016/j.bbamcr.2016.10.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 10/04/2016] [Accepted: 10/11/2016] [Indexed: 12/20/2022]
Abstract
The cochaperone BAG3 is a central protein homeostasis factor in mechanically strained mammalian cells. It mediates the degradation of unfolded and damaged forms of the actin-crosslinker filamin through chaperone-assisted selective autophagy (CASA). In addition, BAG3 stimulates filamin transcription in order to compensate autophagic disposal and to maintain the actin cytoskeleton under strain. Here we demonstrate that BAG3 coordinates protein synthesis and autophagy through spatial regulation of the mammalian target of rapamycin complex 1 (mTORC1). The cochaperone utilizes its WW domain to contact a proline-rich motif in the tuberous sclerosis protein TSC1 that functions as an mTORC1 inhibitor in association with TSC2. Interaction with BAG3 results in a recruitment of TSC complexes to actin stress fibers, where the complexes act on a subpopulation of mTOR-positive vesicles associated with the cytoskeleton. Local inhibition of mTORC1 is essential to initiate autophagy at sites of filamin unfolding and damage. At the same time, BAG3-mediated sequestration of TSC1/TSC2 relieves mTORC1 inhibition in the remaining cytoplasm, which stimulates protein translation. In human muscle, an exercise-induced association of TSC1 with the cytoskeleton coincides with mTORC1 activation in the cytoplasm. The spatial regulation of mTORC1 exerted by BAG3 apparently provides the basis for a simultaneous induction of autophagy and protein synthesis to maintain the proteome under mechanical strain.
Collapse
Affiliation(s)
- Barbara Kathage
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, 53121 Bonn, Germany
| | - Sebastian Gehlert
- German Sport University Cologne, Department of Molecular and Cellular Sport Medicine, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany
| | - Anna Ulbricht
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, 53121 Bonn, Germany
| | - Laura Lüdecke
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, 53121 Bonn, Germany
| | - Victor E Tapia
- Department of Medicinal Immunology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Zacharias Orfanos
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, 53121 Bonn, Germany
| | - Daniela Wenzel
- Institute of Physiology I, Life & Brain Center, University Clinic Bonn, Sigmund Freud Str. 25, 53105 Bonn, Germany
| | - Wilhelm Bloch
- German Sport University Cologne, Department of Molecular and Cellular Sport Medicine, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany
| | - Rudolf Volkmer
- Department of Medicinal Immunology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Bernd K Fleischmann
- Institute of Physiology I, Life & Brain Center, University Clinic Bonn, Sigmund Freud Str. 25, 53105 Bonn, Germany
| | - Dieter O Fürst
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, 53121 Bonn, Germany
| | - Jörg Höhfeld
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, 53121 Bonn, Germany.
| |
Collapse
|
25
|
Rauch JN, Zuiderweg ERP, Gestwicki JE. Non-canonical Interactions between Heat Shock Cognate Protein 70 (Hsc70) and Bcl2-associated Anthanogene (BAG) Co-Chaperones Are Important for Client Release. J Biol Chem 2016; 291:19848-57. [PMID: 27474739 PMCID: PMC5025674 DOI: 10.1074/jbc.m116.742502] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 07/26/2016] [Indexed: 01/17/2023] Open
Abstract
Heat shock cognate protein 70 (Hsc70) regulates protein homeostasis through its reversible interactions with client proteins. Hsc70 has two major domains: a nucleotide-binding domain (NBD), that hydrolyzes ATP, and a substrate-binding domain (SBD), where clients are bound. Members of the BAG family of co-chaperones, including Bag1 and Bag3, are known to accelerate release of both ADP and client from Hsc70. The release of nucleotide is known to be mediated by interactions between the conserved BAG domain and the Hsc70 NBD. However, less is known about the regions required for client release, and it is often assumed that this activity also requires the BAG domain. It is important to better understand this step because it determines how long clients remain in the inactive, bound state. Here, we report the surprising observation that truncated versions of either human Bag1 or Bag3, comprised only the BAG domain, promoted rapid release of nucleotide, but not client, in vitro Rather, we found that a non-canonical interaction between Bag1/3 and the Hsc70 SBD is sufficient for accelerating this step. Moreover, client release did not seem to require the BAG domain or Hsc70 NBD. These results suggest that Bag1 and Bag3 control the stability of the Hsc70-client complex using at least two distinct protein-protein contacts, providing a previously under-appreciated layer of molecular regulation in the human Hsc70 system.
Collapse
Affiliation(s)
- Jennifer N Rauch
- From the Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109 and
| | - Erik R P Zuiderweg
- From the Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109 and
| | - Jason E Gestwicki
- From the Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109 and Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California 94158
| |
Collapse
|
26
|
McDaniel DK, Eden K, Ringel VM, Allen IC. Emerging Roles for Noncanonical NF-κB Signaling in the Modulation of Inflammatory Bowel Disease Pathobiology. Inflamm Bowel Dis 2016; 22:2265-79. [PMID: 27508514 PMCID: PMC4992436 DOI: 10.1097/mib.0000000000000858] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Crohn's disease and ulcerative colitis are common and debilitating manifestations of inflammatory bowel disease (IBD). IBD is characterized by a radical imbalance in the activation of proinflammatory and anti-inflammatory signaling pathways in the gut. These pathways are controlled by NF-κB, which is a master regulator of gene transcription. In IBD patients, NF-κB signaling is often dysregulated resulting in overzealous inflammation. NF-κB activation occurs through 2 distinct pathways, defined as either canonical or noncanonical. Canonical NF-κB pathway activation is well studied in IBD and is associated with the rapid, acute production of diverse proinflammatory mediators, such as COX-2, IL-1β, and IL-6. In contrast to the canonical pathway, the noncanonical or "alternative" NF-κB signaling cascade is tightly regulated and is responsible for the production of highly specific chemokines that tend to be associated with less acute, chronic inflammation. There is a relative paucity of literature regarding all aspects of noncanonical NF-ĸB signaling. However, it is clear that this alternative signaling pathway plays a considerable role in maintaining immune system homeostasis and likely contributes significantly to the chronic inflammation underlying IBD. Noncanonical NF-κB signaling may represent a promising new direction in the search for therapeutic targets and biomarkers associated with IBD. However, significant mechanistic insight is still required to translate the current basic science findings into effective therapeutic strategies.
Collapse
Affiliation(s)
- Dylan K. McDaniel
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061
| | - Kristin Eden
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061
| | - Veronica M. Ringel
- Graduate Program in Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA 24061
| | - Irving C. Allen
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061
- Graduate Program in Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA 24061
| |
Collapse
|
27
|
Stabilizing the Hsp70-Tau Complex Promotes Turnover in Models of Tauopathy. Cell Chem Biol 2016; 23:992-1001. [PMID: 27499529 DOI: 10.1016/j.chembiol.2016.04.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 04/23/2016] [Accepted: 04/27/2016] [Indexed: 12/22/2022]
Abstract
Heat shock protein 70 (Hsp70) is a chaperone that normally scans the proteome and initiates the turnover of some proteins (termed clients) by linking them to the degradation pathways. This activity is critical to normal protein homeostasis, yet it appears to fail in diseases associated with abnormal protein accumulation. It is not clear why Hsp70 promotes client degradation under some conditions, while sparing that protein under others. Here, we used a combination of chemical biology and genetic strategies to systematically perturb the affinity of Hsp70 for the model client, tau. This approach revealed that tight complexes between Hsp70 and tau were associated with enhanced turnover while transient interactions favored tau retention. These results suggest that client affinity is one important parameter governing Hsp70-mediated quality control.
Collapse
|
28
|
Morozova K, Clement CC, Kaushik S, Stiller B, Arias E, Ahmad A, Rauch JN, Chatterjee V, Melis C, Scharf B, Gestwicki JE, Cuervo AM, Zuiderweg ERP, Santambrogio L. Structural and Biological Interaction of hsc-70 Protein with Phosphatidylserine in Endosomal Microautophagy. J Biol Chem 2016; 291:18096-106. [PMID: 27405763 DOI: 10.1074/jbc.m116.736744] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Indexed: 01/10/2023] Open
Abstract
hsc-70 (HSPA8) is a cytosolic molecular chaperone, which plays a central role in cellular proteostasis, including quality control during protein refolding and regulation of protein degradation. hsc-70 is pivotal to the process of macroautophagy, chaperone-mediated autophagy, and endosomal microautophagy. The latter requires hsc-70 interaction with negatively charged phosphatidylserine (PS) at the endosomal limiting membrane. Herein, by combining plasmon resonance, NMR spectroscopy, and amino acid mutagenesis, we mapped the C terminus of the hsc-70 LID domain as the structural interface interacting with endosomal PS, and we estimated an hsc-70/PS equilibrium dissociation constant of 4.7 ± 0.1 μm. This interaction is specific and involves a total of 4-5 lysine residues. Plasmon resonance and NMR results were further experimentally validated by hsc-70 endosomal binding experiments and endosomal microautophagy assays. The discovery of this previously unknown contact surface for hsc-70 in this work elucidates the mechanism of hsc-70 PS/membrane interaction for cytosolic cargo internalization into endosomes.
Collapse
Affiliation(s)
| | | | - Susmita Kaushik
- Developmental Molecular Biology, Albert Einstein College of Medicine, New York, New York 10461
| | - Barbara Stiller
- Developmental Molecular Biology, Albert Einstein College of Medicine, New York, New York 10461
| | - Esperanza Arias
- Developmental Molecular Biology, Albert Einstein College of Medicine, New York, New York 10461
| | - Atta Ahmad
- the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48105, and
| | - Jennifer N Rauch
- the Department of Pharmaceutical Chemistry, University of California at San Francisco, San Francisco, California 94158
| | | | | | | | - Jason E Gestwicki
- the Department of Pharmaceutical Chemistry, University of California at San Francisco, San Francisco, California 94158
| | - Ana-Maria Cuervo
- Developmental Molecular Biology, Albert Einstein College of Medicine, New York, New York 10461
| | - Erik R P Zuiderweg
- the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48105, and
| | | |
Collapse
|
29
|
Baranczak A, Kelly JW. A current pharmacologic agent versus the promise of next generation therapeutics to ameliorate protein misfolding and/or aggregation diseases. Curr Opin Chem Biol 2016; 32:10-21. [PMID: 26859714 DOI: 10.1016/j.cbpa.2016.01.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/14/2016] [Accepted: 01/14/2016] [Indexed: 12/18/2022]
Abstract
The list of protein aggregation-associated degenerative diseases is long and growing, while the portfolio of disease-modifying strategies is very small. In this review and perspective, we assess what has worked to slow the progression of an aggregation-associated degenerative disease, covering the underlying mechanism of pharmacologic action and what we have learned about the etiology of the transthyretin amyloid diseases and likely amyloidoses in general. Next, we introduce emerging therapies that should apply more generally to protein misfolding and/or aggregation diseases, approaches that rely on adapting the protein homeostasis or proteostasis network for disease amelioration.
Collapse
Affiliation(s)
- Aleksandra Baranczak
- Department of Chemistry and The Skaggs Institute for Chemical Biology, La Jolla, CA 92037, USA; Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Jeffery W Kelly
- Department of Chemistry and The Skaggs Institute for Chemical Biology, La Jolla, CA 92037, USA; Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
| |
Collapse
|
30
|
Assimon VA, Southworth DR, Gestwicki JE. Specific Binding of Tetratricopeptide Repeat Proteins to Heat Shock Protein 70 (Hsp70) and Heat Shock Protein 90 (Hsp90) Is Regulated by Affinity and Phosphorylation. Biochemistry 2015; 54:7120-31. [PMID: 26565746 PMCID: PMC4714923 DOI: 10.1021/acs.biochem.5b00801] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Heat shock protein 70 (Hsp70) and heat shock protein 90 (Hsp90) require the help of tetratricopeptide repeat (TPR) domain-containing cochaperones for many of their functions. Each monomer of Hsp70 or Hsp90 can interact with only a single TPR cochaperone at a time, and each member of the TPR cochaperone family brings distinct functions to the complex. Thus, competition for TPR binding sites on Hsp70 and Hsp90 appears to shape chaperone activity. Recent structural and biophysical efforts have improved our understanding of chaperone-TPR contacts, focusing on the C-terminal EEVD motif that is present in both chaperones. To better understand these important protein-protein interactions on a wider scale, we measured the affinity of five TPR cochaperones, CHIP, Hop, DnaJC7, FKBP51, and FKBP52, for the C-termini of four members of the chaperone family, Hsc70, Hsp72, Hsp90α, and Hsp90β, in vitro. These studies identified some surprising selectivity among the chaperone-TPR pairs, including the selective binding of FKBP51/52 to Hsp90α/β. These results also revealed that other TPR cochaperones are only able to weakly discriminate between the chaperones or between their paralogs. We also explored whether mimicking phosphorylation of serine and threonine residues near the EEVD motif might impact affinity and found that pseudophosphorylation had selective effects on binding to CHIP but not other cochaperones. Together, these findings suggest that both intrinsic affinity and post-translational modifications tune the interactions between the Hsp70 and Hsp90 proteins and the TPR cochaperones.
Collapse
Affiliation(s)
| | | | - Jason E. Gestwicki
- Department of Pharmaceutical Chemistry, University of California at San Francisco, San Francisco, CA 94158
| |
Collapse
|
31
|
Thirunavukarasu D, Shi H. Aptamer-Enabled Manipulation of the Hsp70 Chaperone System Suggests a Novel Strategy for Targeted Ubiquitination. Nucleic Acid Ther 2015; 26:20-8. [PMID: 26640962 DOI: 10.1089/nat.2015.0563] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The Hsp70 chaperone system plays an important role in protein quality control by assisting in the folding and clearance of misfolded proteins. However, the mechanism by which it chooses between folding and degradation pathways is not fully understood. In this study, we used an RNA aptamer for Hsp70 to perturb the function of Hsp70 in cell-free systems. We found that the aptamer inhibited both Hsp70-mediated folding and Hsp70-CHIP-mediated ubiquitination/degradation of a misfolded protein substrate. Based on these results, we explored a novel strategy for targeted protein ubiquitination, using an engineered bifunctional aptamer to tether a protein substrate to Hsp70. We demonstrated that increased Hsp70-CHIP-mediated ubiquitination of the tethered protein substrate can be specifically induced by this bifunctional aptamer. This strategy may be useful in selective degradation of disease-causing proteins for therapeutic purposes. In addition, these studies provide insight into the mechanism of Hsp70-mediated protein triage.
Collapse
Affiliation(s)
- Deepak Thirunavukarasu
- Department of Biological Sciences and The RNA Institute, University at Albany, State University of New York , Albany, New York
| | - Hua Shi
- Department of Biological Sciences and The RNA Institute, University at Albany, State University of New York , Albany, New York
| |
Collapse
|
32
|
Eisele YS, Monteiro C, Fearns C, Encalada SE, Wiseman RL, Powers ET, Kelly JW. Targeting protein aggregation for the treatment of degenerative diseases. Nat Rev Drug Discov 2015; 14:759-80. [PMID: 26338154 PMCID: PMC4628595 DOI: 10.1038/nrd4593] [Citation(s) in RCA: 288] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The aggregation of specific proteins is hypothesized to underlie several degenerative diseases, which are collectively known as amyloid disorders. However, the mechanistic connection between the process of protein aggregation and tissue degeneration is not yet fully understood. Here, we review current and emerging strategies to ameliorate aggregation-associated degenerative disorders, with a focus on disease-modifying strategies that prevent the formation of and/or eliminate protein aggregates. Persuasive pharmacological and genetic evidence now supports protein aggregation as the cause of postmitotic tissue dysfunction or loss. However, a more detailed understanding of the factors that trigger and sustain aggregate formation and of the structure-activity relationships underlying proteotoxicity is needed to develop future disease-modifying therapies.
Collapse
Affiliation(s)
- Yvonne S. Eisele
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Cecilia Monteiro
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Colleen Fearns
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Sandra E. Encalada
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla, California 92037, USA
| | - R. Luke Wiseman
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Evan T. Powers
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Jeffery W. Kelly
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| |
Collapse
|
33
|
Soss SE, Rose KL, Hill S, Jouan S, Chazin WJ. Biochemical and Proteomic Analysis of Ubiquitination of Hsc70 and Hsp70 by the E3 Ligase CHIP. PLoS One 2015; 10:e0128240. [PMID: 26010904 PMCID: PMC4444009 DOI: 10.1371/journal.pone.0128240] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 04/23/2015] [Indexed: 01/24/2023] Open
Abstract
The E3 ubiquitin ligase CHIP is involved in protein triage, serving as a co-chaperone for refolding as well as catalyzing ubiquitination of substrates. CHIP functions with both the stress induced Hsp70 and constitutive Hsc70 chaperones, and also plays a role in maintaining their balance in the cell. When the chaperones carry no client proteins, CHIP catalyzes their polyubiquitination and subsequent proteasomal degradation. Although Hsp70 and Hsc70 are highly homologous in sequence and similar in structure, CHIP mediated ubiquitination promotes degradation of Hsp70 with a higher efficiency than for Hsc70. Here we report a detailed and systematic investigation to characterize if there are significant differences in the CHIP in vitro ubiquitination of human Hsp70 and Hsc70. Proteomic analysis by mass spectrometry revealed that only 12 of 39 detectable lysine residues were ubiquitinated by UbcH5a in Hsp70 and only 16 of 45 in Hsc70. The only conserved lysine identified as ubiquitinated in one but not the other heat shock protein was K159 in Hsc70. Ubiquitination assays with K-R ubiquitin mutants showed that multiple Ub chain types are formed and that the distribution is different for Hsp70 versus Hsc70. CHIP ubiquitination with the E2 enzyme Ube2W is predominantly directed to the N-terminal amine of the substrate; however, some internal lysine modifications were also detected. Together, our results provide a detailed view of the differences in CHIP ubiquitination of these two very similar proteins, and show a clear example where substantial differences in ubiquitination can be generated by a single E3 ligase in response to not only different E2 enzymes but subtle differences in the substrate.
Collapse
Affiliation(s)
- Sarah E. Soss
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Kristie L. Rose
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Mass Spectrometry Research Center, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Salisha Hill
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Mass Spectrometry Research Center, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Sophie Jouan
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Walter J. Chazin
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- * E-mail:
| |
Collapse
|
34
|
Yu T, Gao X, Ren Y, Wei D. Assembly of cellulases with synthetic protein scaffolds in vitro. BIORESOUR BIOPROCESS 2015. [DOI: 10.1186/s40643-015-0046-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Abstract
Background
Enzymatic cascades in metabolic pathways are spatially organized in such a way as to facilitate the flow of substrates. The construction of artificial cellulase complexes that mimic natural multienzyme assemblies can potentially enhance the capacity for cellulose hydrolysis. In this study, an artificial cellulase complex was constructed by tethering three cellulases to a synthetic protein scaffold.
Results
Three pairs of interacting proteins were selected and characterized. The artificial protein scaffolds were constructed by fusing three interacting proteins. Cellulases were tethered to these synthetic scaffolds in different orders. The optimal assembly resulted in a 1.5-fold higher hydrolysis of cellulose than that achieved by unassembled cellulases.
Conclusions
A novel artificial protein scaffold was constructed and used to assemble three cellulases. The resultant increase in enzymatic activity suggests that this can be used as a strategy for enhancing the biocatalytic capacity of enzyme cascades.
Collapse
|
35
|
Song J, Kose S, Watanabe A, Son SY, Choi S, Hong H, Yamashita E, Park IY, Imamoto N, Lee SJ. Structural and functional analysis of Hikeshi, a new nuclear transport receptor of Hsp70s. ACTA ACUST UNITED AC 2015; 71:473-83. [PMID: 25760597 DOI: 10.1107/s1399004714026881] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 12/08/2014] [Indexed: 11/10/2022]
Abstract
Hikeshi is a nuclear transport receptor required for cell survival after stress. It mediates heat-shock-induced nuclear import of 70 kDa heat-shock proteins (Hsp70s) through interactions with FG-nucleoporins (FG-Nups), which are proteins in nuclear pore complexes (NPCs). Here, the crystal structure of human Hikeshi is presented at 1.8 Å resolution. Hikeshi forms an asymmetric homodimer that is responsible for the interaction with Hsp70s. The asymmetry of Hikeshi arises from the distinct conformation of the C-terminal domain (CTD) and the flexibility of the linker regions of each monomer. Structure-guided mutational analyses showed that both the flexible linker region and the CTD are important for nuclear import of Hsp70. Pull-down assays revealed that only full-length Hsp70s can interact with Hikeshi. The N-terminal domain (NTD) consists of a jelly-roll/β-sandwich fold structure which contains hydrophobic pockets involved in FG-Nup recognition. A unique extended loop (E-loop) in the NTD is likely to regulate the interactions of Hikeshi with FG-Nups. The crystal structure of Hikeshi explains how Hikeshi participates in the regulation of nuclear import through the recognition of FG-Nups and which part of Hikeshi affects its binding to Hsp70. This study is the first to yield structural insight into this highly unique import receptor.
Collapse
Affiliation(s)
- Jinsue Song
- College of Pharmacy, Chungbuk National University, 48 Gaeshin-dong, Heungduk-gu, Cheongju, Chungbuk 361-763, Republic of Korea
| | - Shingo Kose
- Cellular Dynamics Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Ai Watanabe
- Cellular Dynamics Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Se Young Son
- College of Pharmacy, Chungbuk National University, 48 Gaeshin-dong, Heungduk-gu, Cheongju, Chungbuk 361-763, Republic of Korea
| | - Saehae Choi
- College of Pharmacy, Chungbuk National University, 48 Gaeshin-dong, Heungduk-gu, Cheongju, Chungbuk 361-763, Republic of Korea
| | - Hyerim Hong
- College of Pharmacy, Chungbuk National University, 48 Gaeshin-dong, Heungduk-gu, Cheongju, Chungbuk 361-763, Republic of Korea
| | - Eiki Yamashita
- Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Il Yeong Park
- College of Pharmacy, Chungbuk National University, 48 Gaeshin-dong, Heungduk-gu, Cheongju, Chungbuk 361-763, Republic of Korea
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Soo Jae Lee
- College of Pharmacy, Chungbuk National University, 48 Gaeshin-dong, Heungduk-gu, Cheongju, Chungbuk 361-763, Republic of Korea
| |
Collapse
|
36
|
Zhang H, Amick J, Chakravarti R, Santarriaga S, Schlanger S, McGlone C, Dare M, Nix JC, Scaglione KM, Stuehr DJ, Misra S, Page RC. A bipartite interaction between Hsp70 and CHIP regulates ubiquitination of chaperoned client proteins. Structure 2015; 23:472-482. [PMID: 25684577 DOI: 10.1016/j.str.2015.01.003] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/24/2014] [Accepted: 01/05/2015] [Indexed: 11/16/2022]
Abstract
The ubiquitin ligase CHIP plays an important role in cytosolic protein quality control by ubiquitinating proteins chaperoned by Hsp70/Hsc70 and Hsp90, thereby targeting such substrate proteins for degradation. We present a 2.91 Å resolution structure of the tetratricopeptide repeat (TPR) domain of CHIP in complex with the α-helical lid subdomain and unstructured tail of Hsc70. Surprisingly, the CHIP-TPR interacts with determinants within both the Hsc70-lid subdomain and the C-terminal PTIEEVD motif of the tail, exhibiting an atypical mode of interaction between chaperones and TPR domains. We demonstrate that the interaction between CHIP and the Hsc70-lid subdomain is required for proper ubiquitination of Hsp70/Hsc70 or Hsp70/Hsc70-bound substrate proteins. Posttranslational modifications of the Hsc70 lid and tail disrupt key contacts with the CHIP-TPR and may regulate CHIP-mediated ubiquitination. Our study shows how CHIP docks onto Hsp70/Hsc70 and defines a bipartite mode of interaction between TPR domains and their binding partners.
Collapse
Affiliation(s)
- Huaqun Zhang
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Joseph Amick
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Ritu Chakravarti
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | | | - Simon Schlanger
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Cameron McGlone
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Michelle Dare
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Jay C Nix
- Molecular Biology Consortium, Beamline 4.2.2, Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - K Matthew Scaglione
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Dennis J Stuehr
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Saurav Misra
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
| | - Richard C Page
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| |
Collapse
|
37
|
Abstract
Protein homeostasis relies on a balance between protein folding and protein degradation. Molecular chaperones like Hsp70 and Hsp90 fulfil well-defined roles in protein folding and conformational stability via ATP dependent reaction cycles. These folding cycles are controlled by associations with a cohort of non-client protein co-chaperones, such as Hop, p23 and Aha1. Pro-folding co-chaperones facilitate the transit of the client protein through the chaperone mediated folding process. However, chaperones are also involved in ubiquitin-mediated proteasomal degradation of client proteins. Similar to folding complexes, the ability of chaperones to mediate protein degradation is regulated by co-chaperones, such as the C terminal Hsp70 binding protein (CHIP). CHIP binds to Hsp70 and Hsp90 chaperones through its tetratricopeptide repeat (TPR) domain and functions as an E3 ubiquitin ligase using a modified RING finger domain (U-box). This unique combination of domains effectively allows CHIP to network chaperone complexes to the ubiquitin-proteasome system. This chapter reviews the current understanding of CHIP as a co-chaperone that switches Hsp70/Hsp90 chaperone complexes from protein folding to protein degradation.
Collapse
Affiliation(s)
- Adrienne L Edkins
- Department of Biochemistry and Microbiology, Biomedical Biotechnology Research Unit (BioBRU), Rhodes University, 6140, Grahamstown, South Africa,
| |
Collapse
|
38
|
Taldone T, Ochiana SO, Patel PD, Chiosis G. Selective targeting of the stress chaperome as a therapeutic strategy. Trends Pharmacol Sci 2014; 35:592-603. [PMID: 25262919 DOI: 10.1016/j.tips.2014.09.001] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 08/28/2014] [Accepted: 09/02/2014] [Indexed: 12/11/2022]
Abstract
Normal cellular function is maintained by coordinated proteome machinery that performs a vast array of activities. Helping the proteome in such roles is the chaperome, a network of molecular chaperones and folding enzymes. The stressed cell contains, at any time, a complex mixture of chaperome complexes; a majority performs 'housekeeping functions' similarly to non-stressed, normal cells, but a finely-tuned fraction buffers the proteome altered by chronic stress. The stress chaperome is epigenetically distinct from its normal, housekeeping counterpart, providing a basis for its selective targeting by small molecules. We discuss here the development of chaperome inhibitors, and how agents targeting chaperome members in stressed cells are in fact being directed towards chaperome complexes, and their effect is therefore determined by their ability to sample and engage such complexes. A new approach is needed to target and implement chaperome modulators in the investigation of diseases, and we propose that the classical thinking in drug discovery needs adjustment when developing chaperome-targeting drugs.
Collapse
Affiliation(s)
- Tony Taldone
- Program in Molecular Pharmacology and Chemistry and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Stefan O Ochiana
- Program in Molecular Pharmacology and Chemistry and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Pallav D Patel
- Program in Molecular Pharmacology and Chemistry and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Gabriela Chiosis
- Program in Molecular Pharmacology and Chemistry and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| |
Collapse
|
39
|
Kim D, Friedman AD, Liu R. Tetraspecific ligand for tumor-targeted delivery of nanomaterials. Biomaterials 2014; 35:6026-36. [PMID: 24786763 DOI: 10.1016/j.biomaterials.2014.04.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 04/05/2014] [Indexed: 12/18/2022]
Abstract
The polygenetic nature of most cancers emphasizes the necessity of cancer therapies that target multiple essential signaling pathways. However, there is a significant paucity of targeting ligands with multi-specificities for targeted delivery of biomaterials. To address this unmet need, we generated a tetraspecific targeting ligand that recognizes four different cancer biomarkers, including VEGFR2, αvβ3 integrin, EGFR, and HER2 receptors, which have been implicated in numerous malignant tumors. The tetraspecific targeting ligand was constructed by sequentially connecting four targeting ligand subunits via flexible linkers, yielding a fusion protein that can be highly expressed in Escherichia coli and readily purified to near homogeneity. Surface Plasmon Resonance (SPR), Bio-Layer Interferometry (BLI) studies and extensive cellular binding analyses indicated that all the targeting ligand subunits in the tetraspecific fusion protein recognized their target receptors proximately to the corresponding monospecific ligands. The resulting tetraspecific targeting ligand was applied for the delivery of nanomaterials such as gold nanoparticles (AuNPs) for targeted hyperthermic killing of various cancer cell lines with biomarkers of interest expressed. We demonstrate that the tetraspecific ligand can be facilely introduced on the surface of AuNPs and efficient target-dependent killing of cancer cells can be achieved only when the AuNPs are conjugated with the tetraspecific ligand. Significantly, the tetraspecific ligand simultaneously interacts with more than one receptors, such as EGFR and HER2 receptors, when they are expressed on the surface of the same cell, as demonstrated by in vitro binding assays and cell binding analyses. Our results demonstrate that the tetraspecific ligand, through multivalency and synergistic binding, can be readily used to generate various 'smart' biomaterials with greatly broadened tumor targeting range for simultaneous targeting of multiple signaling pathways on many different cancer types.
Collapse
Affiliation(s)
- Dongwook Kim
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599-7568, USA; Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, NC 27599-7264, USA
| | - Adam D Friedman
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599-7568, USA; Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, NC 27599-7264, USA
| | - Rihe Liu
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599-7568, USA; Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, NC 27599-7264, USA.
| |
Collapse
|
40
|
Connarn JN, Assimon VA, Reed RA, Tse E, Southworth DR, Zuiderweg ERP, Gestwicki JE, Sun D. The molecular chaperone Hsp70 activates protein phosphatase 5 (PP5) by binding the tetratricopeptide repeat (TPR) domain. J Biol Chem 2013; 289:2908-17. [PMID: 24327656 DOI: 10.1074/jbc.m113.519421] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Protein phosphatase 5 (PP5) is auto-inhibited by intramolecular interactions with its tetratricopeptide repeat (TPR) domain. Hsp90 has been shown to bind PP5 to activate its phosphatase activity. However, the functional implications of binding Hsp70 to PP5 are not yet clear. In this study, we find that both Hsp90 and Hsp70 bind to PP5 using a luciferase fragment complementation assay. A fluorescence polarization assay shows that Hsp90 (MEEVD motif) binds to the TPR domain of PP5 almost 3-fold higher affinity than Hsp70 (IEEVD motif). However, Hsp70 binding to PP5 stimulates higher phosphatase activity of PP5 than the binding of Hsp90. We find that PP5 forms a stable 1:1 complex with Hsp70, but the interaction appears asymmetric with Hsp90, with one PP5 binding the dimer. Solution NMR studies reveal that Hsc70 and PP5 proteins are dynamically independent in complex, tethered by a disordered region that connects the Hsc70 core and the IEEVD-TPR contact area. This tethered binding is expected to allow PP5 to carry out multi-site dephosphorylation of Hsp70-bound clients with a range of sizes and shapes. Together, these results demonstrate that Hsp70 recruits PP5 and activates its phosphatase activity which suggests dual roles for PP5 that might link chaperone systems with signaling pathways in cancer and development.
Collapse
|
41
|
Rauch JN, Gestwicki JE. Binding of human nucleotide exchange factors to heat shock protein 70 (Hsp70) generates functionally distinct complexes in vitro. J Biol Chem 2013; 289:1402-14. [PMID: 24318877 DOI: 10.1074/jbc.m113.521997] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Proteins with Bcl2-associated anthanogene (BAG) domains act as nucleotide exchange factors (NEFs) for the molecular chaperone heat shock protein 70 (Hsp70). There are six BAG family NEFs in humans, and each is thought to link Hsp70 to a distinct cellular pathway. However, little is known about how the NEFs compete for binding to Hsp70 or how they might differentially shape its biochemical activities. Toward these questions, we measured the binding of human Hsp72 (HSPA1A) to BAG1, BAG2, BAG3, and the unrelated NEF Hsp105. These studies revealed a clear hierarchy of affinities: BAG3 > BAG1 > Hsp105 ≫ BAG2. All of the NEFs competed for binding to Hsp70, and their relative affinity values predicted their potency in nucleotide and peptide release assays. Finally, we combined the Hsp70-NEF pairs with cochaperones of the J protein family (DnaJA1, DnaJA2, DnaJB1, and DnaJB4) to generate 16 permutations. The activity of the combinations in ATPase and luciferase refolding assays were dependent on the identity and stoichiometry of both the J protein and NEF so that some combinations were potent chaperones, whereas others were inactive. Given the number and diversity of cochaperones in mammals, it is likely that combinatorial assembly could generate a large number of distinct permutations.
Collapse
Affiliation(s)
- Jennifer N Rauch
- From the Departments of Biochemistry and Pathology and the Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109 and
| | | |
Collapse
|
42
|
Pashkov BM. [Peculiarities of the clinical picture of some dermatoses localized in the buccal mucosa]. Exp Cell Res 1970; 353:46-53. [PMID: 28279658 PMCID: PMC5381905 DOI: 10.1016/j.yexcr.2017.03.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 02/22/2017] [Accepted: 03/04/2017] [Indexed: 01/14/2023]
|