title: Rines/RNF180, a novel RING finger gene-encoded product, is a membrane-bound ubiquitin ligase.
abstract: We identified and characterized a novel RING finger gene, Rines/RNF180, which is well conserved among vertebrates. Putative Rines gene product (Rines) contains a RING finger domain, a basic coiled-coil domain, a novel conserved domain (DSPRC) and a C-terminal hydrophobic region that is predicted to be a transmembrane domain. N-terminally epitope tagged-Rines (Nt-Rines) was detected in the endoplasmic reticulum membrane/nuclear envelope in cultured mammalian cells. Nt-Rines was not extracted by high salt or alkaline buffers and was degraded in intact endoplasmic reticulum treated with proteinase K, indicating that Nt-Rines is an integral membrane protein with most of its N-terminal regions in the cytoplasm. Rines was expressed in brain, kidney, testis and uterus of adult mice, and in developing lens and brain, particularly in the ventricular layer of the cerebral cortex at embryonic stages. In cultured cells, Nt-Rines can bind another protein and promoted its degradation. The degradation was inhibited by proteasomal inhibitors. In addition, Nt-Rines itself was heavily ubiquitinated and degraded by proteasome. The involvement of Rines in the ubiquitin-proteasome pathway was further supported by its binding to the UbcH6 ubiquitin-conjugating enzyme and by its trans-ubiquitination enhancing activities. These results suggest that Rines is a membrane-bound E3 ubiquitin ligase.
authors: Laboratory for Comparative Neurogenesis, RIKEN Brain Science Institute, Wako-shi, Saitama 351-0198, Japan.
authors: Miyuki
authors: M
authors: Ogawa
authors: Kiyomi
authors: K
authors: Mizugishi
authors: Akira
authors: A
authors: Ishiguro
authors: Yoshio
authors: Y
authors: Koyabu
authors: Yuzuru
authors: Y
authors: Imai
authors: Ryosuke
authors: R
authors: Takahashi
authors: Katsuhiko
authors: K
authors: Mikoshiba
authors: Jun
authors: J
authors: Aruga
mesh_terms: D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D017931:DNA Primers / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008297:Male; D008566:Membranes / Q000201:enzymology; D051379:Mice; D008813:Mice, Inbred ICR; D041681:NIH 3T3 Cells; D011247:Pregnancy; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D054829:RING Finger Domains; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014018:Tissue Distribution; D014162:Transfection; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D011994:Recombinant Proteins; D044767:Ubiquitin-Protein Ligases; D046988:Proteasome Endopeptidase Complex