Troglitazone reduces heat shock protein 70 content in primary rat hepatocytes by a ubiquitin proteasome independent mechanism

2003 ◽  
Author(s):  
G Davies
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 70 ◽  
Rat Hepatocytes ◽  
Primary Rat Hepatocytes ◽  
Independent Mechanism ◽  
Ubiquitin Proteasome

scholarly journals Heat Shock Protein 70 Regulates Degradation of the Mumps Virus Phosphoprotein via the Ubiquitin-Proteasome Pathway

2014 ◽  
Vol 89 (6) ◽  
pp. 3188-3199 ◽  
Author(s):  
Hiroshi Katoh ◽  
Toru Kubota ◽  
Shunsuke Kita ◽  
Yuichiro Nakatsu ◽  
Natsuko Aoki ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 70 ◽  
Cytoplasmic Inclusion ◽  
Mumps Virus ◽  
Viral Rna ◽  
Ubiquitin Proteasome Pathway ◽  
P Protein ◽  
Ubiquitin Proteasome ◽  
Proteasome Pathway

ABSTRACTMumps virus (MuV) infection induces formation of cytoplasmic inclusion bodies (IBs). Growing evidence indicates that IBs are the sites where RNA viruses synthesize their viral RNA. However, in the case of MuV infection, little is known about the viral and cellular compositions and biological functions of the IBs. In this study, pulldown purification and N-terminal amino acid sequencing revealed that stress-inducible heat shock protein 70 (Hsp72) was a binding partner of MuV phosphoprotein (P protein), which was an essential component of the IB formation. Immunofluorescence and immunoblotting analyses revealed that Hsp72 was colocalized with the P protein in the IBs, and its expression was increased during MuV infection. Knockdown of Hsp72 using small interfering RNAs (siRNAs) had little, if any, effect on viral propagation in cultured cells. Knockdown of Hsp72 caused accumulation of ubiquitinated P protein and delayed P protein degradation. These results show that Hsp72 is recruited to IBs and regulates the degradation of MuV P protein through the ubiquitin-proteasome pathway.IMPORTANCEFormation of cytoplasmic inclusion bodies (IBs) is a common characteristic feature in mononegavirus infections. IBs are considered to be the sites of viral RNA replication and transcription. However, there have been few studies focused on host factors recruited to the IBs and their biological functions. Here, we identified stress-inducible heat shock protein 70 (Hsp72) as the first cellular partner of mumps virus (MuV) phosphoprotein (P protein), which is an essential component of the IBs and is involved in viral RNA replication/transcription. We found that the Hsp72 mobilized to the IBs promoted degradation of the MuV P protein through the ubiquitin-proteasome pathway. Our data provide new insight into the role played by IBs in mononegavirus infection.

Neuronal DnaJ proteins HSJ1a and HSJ1b: a role in linking the Hsp70 chaperone machine to the ubiquitin–proteasome system?

2004 ◽  
Vol 32 (4) ◽  
pp. 640-642 ◽  
Author(s):  
J.P. Chapple ◽  
J. van der Spuy ◽  
S. Poopalasundaram ◽  
M.E. Cheetham
Keyword(s):  
Protein Folding ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 70 ◽  
Ubiquitin Proteasome System ◽  
Cellular Protein ◽  
Hsp70 Chaperone ◽  
Ubiquitin Proteasome ◽  
Cellular Processing

The heat-shock protein 70 chaperone machine is functionally connected to the ubiquitin–proteasome system by the co-chaperone CHIP. In this article, we discuss evidence that the neuronal DnaJ proteins HSJ1a and HSJ1b may represent a further link between the cellular protein folding and degradation machineries. We have demonstrated that HSJ1 proteins contain putative ubiquitin interaction motifs and can modulate the cellular processing of rhodopsin, a protein that is targeted for degradation by the proteasome when it is misfolded.

scholarly journals The Degradation of Apolipoprotein B100 Is Mediated by the Ubiquitin-proteasome Pathway and Involves Heat Shock Protein 70

1997 ◽  
Vol 272 (33) ◽  
pp. 20427-20434 ◽  
Author(s):  
Edward A. Fisher ◽  
Mingyue Zhou ◽  
Deborah M. Mitchell ◽  
Xujun Wu ◽  
Satoshi Omura ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 70 ◽  
Ubiquitin Proteasome Pathway ◽  
Apolipoprotein B100 ◽  
Ubiquitin Proteasome ◽  
Proteasome Pathway

Heat shock protein 70 overexpression does not attenuate atrophy in botulinum neurotoxin type A-treated skeletal muscle

2015 ◽  
Vol 119 (1) ◽  
pp. 83-92 ◽  
Author(s):  
Fraser E. Houston ◽  
Brian A. Hain ◽  
Thomas J. Adams ◽  
Kati L. Houston ◽  
Roderic O'Keeffe ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 70 ◽  
Botulinum Neurotoxin ◽  
Transcriptional Activity ◽  
Type A ◽  
Proteasome Activity ◽  
Cross Sectional ◽  
Botulinum Neurotoxin Type A ◽  
Ubiquitin Proteasome

Botulinum neurotoxin type A (BoNT/A) is used clinically to induce therapeutic chemical denervation of spastically contracted skeletal muscles. However, BoNT/A administration can also cause atrophy. We sought to determine whether a major proteolytic pathway contributing to atrophy in multiple models of muscle wasting, the ubiquitin proteasome system (UPS), is involved in BoNT/A-induced atrophy. Three and ten days following BoNT/A injection of rat hindlimb, soleus muscle fiber cross-sectional area was reduced 25 and 65%, respectively. The transcriptional activity of NF-κB and Foxo was significantly elevated at 3 days (2- to 4-fold) and 10 days (5- to 6-fold). Muscle RING-finger protein-1 (MuRF1) activity was elevated (2-fold) after 3 days but not 10 days, while atrogin-1 activity was not elevated at any time point. BoNT/A-induced polyubiquitination occurred after 3 days (3-fold increase) but was totally absent after 10 days. Proteasome activity was elevated (1.5- to 2-fold) after 3 and 10 days. We employed the use of heat shock protein 70 (Hsp70) to inhibit NF-κB and Foxo transcriptional activity. Electrotransfer of Hsp70 into rat soleus, before BoNT/A administration, was insufficient to attenuate atrophy. It was also insufficient to decrease BoNT/A-induced Foxo activity at 3 days, although NF-κB activity was abolished. By 10 days both NF-κB and Foxo activation were abolished by Hsp70. Hsp70-overexpression was unable to alter the levels of BoNT/A-induced effects on MuRF1/atrogin-1, polyubiquitination, or proteasome activity. In conclusion, Hsp70 overexpression is insufficient to attenuate BoNT/A-induced atrophy. It remains unclear what proteolytic mechanism/s are contributing to BoNT/A-induced atrophy, although a Foxo-MuRF1-ubiquitin-proteasome contribution may exist, at least in early BoNT/A-induced atrophy. Further clarification of UPS involvement in BoNT/A-induced atrophy is warranted.

Glycyrrhizin effects rat hepatocytes via the reduction of heat shock protein 90 expression

2001 ◽  
Vol 120 (5) ◽  
pp. A357-A357
Author(s):  
T YOH ◽  
T NAKASHIMA ◽  
Y SUMIDA ◽  
Y KAKISAKA ◽  
H ISHIKAWA ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 90 ◽  
Rat Hepatocytes

Ammonia aggravates emotional stress-induced gastric mucosal oxidative injury through the cancellation of heat shock protein 70 (HSP70)

2001 ◽  
Vol 120 (5) ◽  
pp. A152-A152
Author(s):  
H SUZUKI ◽  
S NAGAHASHI ◽  
M MIYAZAWA ◽  
M MORI ◽  
H NAGATA ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Emotional Stress ◽  
Heat Shock Protein 70 ◽  
Oxidative Injury
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