Proteasomal subunit

The 26S proteasome, a protein complex consisting of a 20S proteasome and a pair of 19S regulatory particles (RP), is involved in ATP-dependent proteolysis in eukaryotes. In yeast, theRP contains six different ATPase subunits and, at least, 11 non-ATPase subunits. In this study, we identi®ed the rice homologs of yeast RP subunit genes from the rice expressed sequence tag (EST) library.

10p research12 29-04-2013 41 3   Download

Metabolically unstable proteins are involved in a multitude of regulatory networks, including those that control cell signaling, the cell cycle and in many responses to physiological stress. In the present study, we have deter-mined the stability and characterized the degradation process of some members of the Gq class of heterotrimeric G proteins. Pulse-chase experi-ments in HEK293 cells indicated a rapid turnover of endogenously expressed Gaq and overexpressed Gaq and Ga16 subunits.

13p fptmusic 12-04-2013 39 2   Download

The COP9 signalosome (CSN) occurs in all eukaryotic cells. It is a regula-tory particle of the ubiquitin (Ub)⁄26S proteasome system. The eight sub-units of the CSN possess sequence homologies with the polypeptides of the 26S proteasome lid complex and just like the lid, the CSN consists of six subunits with PCI (proteasome, COP9 signalosome, initiation factor 3) domains and two components with MPN (Mpr-Pad1-N-terminal) domains.

9p fptmusic 11-04-2013 23 1   Download

Parkinson’s disease is characterized by the loss of dopaminergic neurons in the nigrostriatal pathway accompanied by the presence of intracellular cytoplasmic inclusions, termed Lewy bodies. Fibrillized a-synuclein forms the major component of Lewy bodies. We reported a specific interaction between rata-synuclein and tat binding protein 1, a subunit of PA700, the regulatory complex of the 26S proteasome.

11p fptmusic 11-04-2013 39 2   Download

The Rpn10 subunit of the 26S proteasome can bind to polyubiqui-tinoylated and⁄or ubiquitin-like proteins via ubiquitin-interacting motifs (UIMs). Vertebrate Rpn10 consists of five distinct spliced isoforms, but the specific functions of these variants remain largely unknown.

14p dell39 27-03-2013 47 4   Download

We performed a functional genetic screen to find novel antiapoptotic genes that are under the regulation of the oncoprotein c-Src. Several clones were identified, including subunit S5a of the 26Sproteasome. We found that S5a rescued Saos-2 cells from apoptosis induced by Src inhibitor 4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP1).

17p galaxyss3 19-03-2013 31 2   Download

The recognition of ubiquitylated substrates is an essential element of ubiqu-itin⁄26S proteasome-mediated proteolysis (UPP), which is mediated directly by the proteasome subunit RPN10 and⁄or RPN13, or indirectly by ubiquitin receptors containing ubiquitin-like and ubiquitin-associated domains. By pull-down and mutagenesis assays, we detected cross-species divergence of the major recognition pathways.

21p mobifone23 18-01-2013 36 4   Download

Polyubiquitin receptors execute the targeting of polyubiquitylated proteins to the 26S proteasome. In vitro studies indicate that disturbance of the physiological balance among different receptor proteins impairs the prote-asomal degradation of polyubiquitylated proteins.

12p cosis54 08-12-2012 42 3   Download