scholarly journals The Heat Shock Protein 40-Type Chaperone MASH Supports the Endoplasmic Reticulum-Associated Degradation E3 Ubiquitin Ligase MAKIBISHI1 in Medicago truncatula

2021 ◽  
Vol 12 ◽  
Author(s):  
Marie-Laure Erffelinck ◽  
Bianca Ribeiro ◽  
Lore Gryffroy ◽  
Avanish Rai ◽  
Jacob Pollier ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Medicago Truncatula ◽  
Ubiquitin Ligase ◽  
Protein Quality ◽  
E3 Ubiquitin Ligase ◽  
Metabolic Phenotype ◽  
Endoplasmic Reticulum Associated Degradation ◽  
Control Apparatus

Jasmonates (JA) are oxylipin-derived phytohormones that trigger the production of specialized metabolites that often serve in defense against biotic stresses. In Medicago truncatula, a JA-induced endoplasmic reticulum-associated degradation (ERAD)-type machinery manages the production of bioactive triterpenes and thereby secures correct plant metabolism, growth, and development. This machinery involves the conserved RING membrane-anchor (RMA)-type E3 ubiquitin ligase MAKIBISHI1 (MKB1). Here, we discovered two additional members of this protein control apparatus via a yeast-based protein–protein interaction screen and characterized their function. First, a cognate E2 ubiquitin-conjugating enzyme was identified that interacts with MKB1 to deliver activated ubiquitin and to mediate its ubiquitination activity. Second, we identified a heat shock protein 40 (HSP40) that interacts with MKB1 to support its activity and was therefore designated MKB1-supporting HSP40 (MASH). MASH expression was found to be co-regulated with that of MKB1. The presence of MASH is critical for MKB1 and ERAD functioning because the dramatic morphological, transcriptional, and metabolic phenotype of MKB1 knock-down M. truncatula hairy roots was phenocopied by silencing of MASH. Interaction was also observed between the Arabidopsis thaliana (Arabidopsis) homologs of MASH and MKB1, suggesting that MASH represents an essential and plant-specific component of this vital and conserved eukaryotic protein quality control machinery.

scholarly journals Characterization of protein complexes of the endoplasmic reticulum-associated degradation E3 ubiquitin ligase Hrd1

2017 ◽  
Vol 292 (22) ◽  
pp. 9104-9116 ◽  
Author(s):  
Jiwon Hwang ◽  
Christopher P. Walczak ◽  
Thomas A. Shaler ◽  
James A. Olzmann ◽  
Lichao Zhang ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Ubiquitin Ligase ◽  
Protein Complexes ◽  
E3 Ubiquitin Ligase ◽  
Endoplasmic Reticulum Associated Degradation

scholarly journals AAA ATPase p97/Valosin-containing Protein Interacts with gp78, a Ubiquitin Ligase for Endoplasmic Reticulum-associated Degradation

2004 ◽  
Vol 279 (44) ◽  
pp. 45676-45684 ◽  
Author(s):  
Xiaoyan Zhong ◽  
Yuxian Shen ◽  
Petek Ballar ◽  
Andria Apostolou ◽  
Reuven Agami ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Ubiquitin Ligase ◽  
Protein Quality ◽  
Proteasomal Degradation ◽  
Degradation Pathway ◽  
Aaa Atpase ◽  
Endoplasmic Reticulum Associated Degradation ◽  
Ubiquitin Ligase E3 ◽  
Quality Control Mechanism ◽  
Interacting Domain

Endoplasmic reticulum-associated degradation (ERAD) is a protein quality control mechanism that eliminates unwanted proteins from the endoplasmic reticulum (ER) through a ubiquitin-dependent proteasomal degradation pathway. gp78 is a previously described ER membrane-anchored ubiquitin ligase (E3) involved in ubiquitination of ER proteins. AAA ATPase (ATPase associated with various cellular activities) p97/valosin-containing protein (VCP) subsequently dislodges the ubiquitinated proteins from the ER and chaperones them to the cytosol, where they undergo proteasomal degradation. We now report that gp78 physically interacts with p97/VCP and enhances p97/VCP-polyubiquitin association. The enhanced association correlates with decreases in ER stress-induced accumulation of polyubiquitinated proteins. This effect is abolished when the p97/VCP-interacting domain of gp78 is removed. Further, using ERAD substrate CD3δ, gp78 consistently enhances p97/VCP-CD3δ binding and facilitates CD3δ degradation. Moreover, inhibition of endogenous gp78 expression by RNA interference markedly increases the levels of total polyubiquitinated proteins, including CD3δ, and abrogates VCP-CD3δ interactions. The gp78 mutant with deletion of its p97/VCP-interacting domain fails to increase CD3δ degradation and leads to accumulation of polyubiquitinated CD3δ, suggesting a failure in delivering ubiquitinated CD3δ for degradation. These data suggest that gp78-p97/VCP interaction may represent one way of coupling ubiquitination with retrotranslocation and degradation of ERAD substrates.

scholarly journals Heat Shock Protein Cognate 70-4 and an E3 Ubiquitin Ligase, CHIP, Mediate Plastid-Destined Precursor Degradation through the Ubiquitin-26S Proteasome System in Arabidopsis

2009 ◽  
Vol 21 (12) ◽  
pp. 3984-4001 ◽  
Author(s):  
Sookjin Lee ◽  
Dong Wook Lee ◽  
Yongjik Lee ◽  
Ulrike Mayer ◽  
York-Dieter Stierhof ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
26S Proteasome

Abstract 18: Synoviolin, an E3 Ubiquitin Ligase, Modulates Cardiac Myocyte Size and Restores Heart Function in Hypertrophic Cardiomyopathy

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Shirin Doroudgar ◽  
Mirko Völkers ◽  
Donna J Thuerauf ◽  
Ashley Bumbar ◽  
Mohsin Khan ◽  
...  
Keyword(s):  
Ubiquitin Ligase ◽  
Protein Misfolding ◽  
Cardiac Myocyte ◽  
Protein Quality ◽  
Heart Function ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
Calcium Handling ◽  
Loss Of Function

The endoplasmic reticulum (ER) is essential for protein homeostasis, or proteostasis, which governs the balance of the proteome. In addition to secreted and membrane proteins, proteins bound for many other cellular locations are also made on ER-bound ribosomes, emphasizing the importance of protein quality and quantity control in the ER. Unlike cytosolic E3 ubiquitin ligases studied in the heart, synoviolin/Hrd1, which has not been studied in the heart, is an ER transmembrane E3 ubiquitin ligase, which we found to be upregulated upon protein misfolding in cardiac myocytes. Given the strategic location of synoviolin in the ER membrane, we addressed the hypothesis that synoviolin is critical for regulating the balance of the proteome, and accordingly, myocyte size. We showed that in vitro, adenovirus-mediated overexpression of synoviolin decreased cardiac myocyte size and protein synthesis, but unlike atrophy-related ubiquitin ligases, synoviolin did not increase global protein degradation. Furthermore, targeted gene therapy using adeno-associated virus 9 (AAV9) showed that overexpression of synoviolin in the left ventricle attenuated maladaptive cardiac hypertrophy and preserved cardiac function in mice subjected to trans-aortic constriction (AAV9-control TAC = 22.5 ± 6.2% decrease in EF vs. AAV9-synoviolin TAC at 6 weeks post TAC; P<0.001), and decreased mTOR activity. Since calcium is a major regulator of cardiac myocyte size, we examined the effects of synoviolin gain- or loss-of-function, using AAV9-synoviolin, or an miRNA designed to knock down synoviolin, respectively. While synoviolin gain-of-function did not affect calcium handling in isolated adult myocytes, synoviolin loss-of-function increased calcium transient amplitude (P<0.01), prolonged spark duration (P<0.001), and increased spark width (P<0.001). Spark frequency and amplitude were unaltered upon synoviolin gain- or loss-of-function. Whereas SR calcium load was unaltered by synoviolin loss-of-function, SERCA-mediated calcium removal was reduced (P<0.05). In conclusion, our studies suggest that in the heart, synoviolin is 1) a critical component of proteostasis, 2) a novel determinant of cardiac myocyte size, and 3) necessary for proper calcium handling.

scholarly journals The Endoplasmic Reticulum-resident Heat Shock Protein Gp96 Activates Dendritic Cells via the Toll-like Receptor 2/4 Pathway

2002 ◽  
Vol 277 (23) ◽  
pp. 20847-20853 ◽  
Author(s):  
Ramunas M. Vabulas ◽  
Sibylla Braedel ◽  
Norbert Hilf ◽  
Harpreet Singh-Jasuja ◽  
Sylvia Herter ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Dendritic Cells ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Toll Like Receptor ◽  
Heat Shock Protein Gp96 ◽  
Toll Like Receptor 2

scholarly journals Calreticulin, a Peptide-binding Chaperone of the Endoplasmic Reticulum, Elicits Tumor- and Peptide-specific Immunity

1999 ◽  
Vol 189 (5) ◽  
pp. 797-802 ◽  
Author(s):  
Sreyashi Basu ◽  
Pramod K. Srivastava
Keyword(s):  
Endoplasmic Reticulum ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Antigen Processing ◽  
Peptide Binding ◽  
Cd8 T Cell ◽  
T Cell Response ◽  
Specific Immunity ◽  
Per Se

Calreticulin (CRT), a peptide-binding heat shock protein (HSP) of the endoplasmic reticulum (ER), has been shown previously to associate with peptides transported into the ER by transporter associated with antigen processing (Spee, P., and J. Neefjes. 1997. Eur. J. Immunol. 27: 2441–2449). Our studies show that CRT preparations purified from tumors elicit specific immunity to the tumor used as the source of CRT but not to an antigenically distinct tumor. The immunogenicity is attributed to the peptides associated with the CRT molecule and not to the CRT molecule per se. It is further shown that CRT molecules can be complexed in vitro to unglycosylated peptides and used to elicit peptide-specific CD8+ T cell response in spite of exogenous administration. These characteristics of CRT closely resemble those of HSPs gp96, hsp90, and hsp70, although CRT has no apparent structural homologies to them.

Sign in / Sign up

Export Citation Format

Share Document