The Ubiquitin-associated Domain of hPLIC-2 Interacts with the Proteasome
AUTOR(ES)
Kleijnen, Maurits F.
FONTE
The American Society for Cell Biology
RESUMO
The ubiquitin-like hPLIC proteins can associate with proteasomes, and hPLIC overexpression can specifically interfere with ubiquitin-mediated proteolysis (Kleijnen et al., 2000). Because the hPLIC proteins can also interact with certain E3 ubiquitin protein ligases, they may provide a link between the ubiquitination and proteasomal degradation machineries. The amino-terminal ubiquitin-like (ubl) domain is a proteasome-binding domain. Herein, we report that there is a second proteasome-binding domain in hPLIC-2: the carboxyl-terminal ubiquitin-associated (uba) domain. Coimmunoprecipitation experiments of wild-type and mutant hPLIC proteins revealed that the ubl and uba domains each contribute independently to hPLIC-2–proteasome binding. There is specificity for the interaction of the hPLIC-2 uba domain with proteasomes, because uba domains from several other proteins failed to bind proteasomes. Furthermore, the binding of uba domains to polyubiquitinated proteins does not seem to be sufficient for the proteasome binding. Finally, the uba domain is necessary for the ability of full-length hPLIC-2 to interfere with the ubiquitin-mediated proteolysis of p53. The PLIC uba domain has been reported to bind and affect the functions of proteins such as GABAA receptor and presenilins. It is possible that the function of these proteins may be regulated or mediated through proteasomal degradation pathways.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=196580Documentos Relacionados
- Dosage Suppressors of pds1 Implicate Ubiquitin-Associated Domains in Checkpoint Control
- Ubiquitin-associated (UBA) domains in Rad23 bind ubiquitin and promote inhibition of multi-ubiquitin chain assembly
- Structural Requirements for the Ubiquitin-associated Domain of the mRNA Export Factor Mex67 to Bind Its Specific Targets, the Transcription Elongation THO Complex Component Hpr1 and Nucleoporin FXFG Repeats*
- RFPL4 interacts with oocyte proteins of the ubiquitin-proteasome degradation pathway
- Sepsis is associated with increased mRNAs of the ubiquitin-proteasome proteolytic pathway in human skeletal muscle.