Mouse homologue of yeast Prp19 interacts with mouse SUG1, the regulatory subunit of 26S proteasome.
Yeast Prp19 has been shown to involve in pre-mRNA splicing and DNA repair as well as being an ubiquitin ligase. Mammalian homologue of yeast Prp19 also plays on similar functional activities in cells. In the present study, we isolated mouse SUG1 (mSUG1) as binding partner of mouse Prp19 (mPrp19) by the yeast two-hybrid system. We confirmed the interaction of mPrp9 with mSUG1 by GST pull-down assay and co-immunoprecipitation assay. The N-terminus of mPrp19 including U-box domain was associated with the C-terminus of mSUG1. Although, mSUG1 is a regulatory subunit of 26S proteasome, mPrp19 was not degraded in the proteasome-dependent pathway. Interestingly, GFP-mPrp19 fusion protein was co-localized with mSUG1 protein in cytoplasm as the formation of the speckle-like structures in the presence of a proteasome inhibitor MG132. In addition, the activity of proteasome was increased in cells transfected with mPrp19. Taken together, these results suggest that mPrp19 involves the regulation of protein turnover and may transport its substrates to 26S proteasome through mSUG1 protein.
Sihn
Choong-Ryoul
CR
Department of Biology, Kyung Hee University, Seoul 130-701, Republic of Korea.
Cho
Si Young
SY
Lee
Jeong Ho
JH
Lee
Tae Ryong
TR
Kim
Sang Hoon
SH
D000074183:ATPases Associated with Diverse Cellular Activities; D000818:Animals; D001665:Binding Sites; D015153:Blotting, Western; D045744:Cell Line, Tumor; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation; D007763:Lac Operon / Q000235:genetics; D007976:Leupeptins / Q000494:pharmacology; D051379:Mice; D008856:Microscopy, Fluorescence; D034521:Nuclear Matrix-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism*; D061988:Proteasome Inhibitors; D011485:Protein Binding; D021122:Protein Subunits / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D000072260:RNA Splicing Factors; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D017381:Spliceosomes; D014162:Transfection; D020798:Two-Hybrid System Techniques
D015853:Cysteine Proteinase Inhibitors; D007976:Leupeptins; D034521:Nuclear Matrix-Associated Proteins; C079877:PRP19 protein, S cerevisiae; D061988:Proteasome Inhibitors; D021122:Protein Subunits; C518638:Prpf19 protein, mouse; C491455:Psmc5 protein, mouse; D000072260:RNA Splicing Factors; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins; D005982:Glutathione Transferase; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease; D000074183:ATPases Associated with Diverse Cellular Activities; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde