Title:
Genetic and functional diversity of TRIM family E3 ubiquitin ligeses
Shigetsugu Hatakeyama
Professor
Department of Biochemistry, Hokkaido University Graduate School of Medicine, Sapporo , Japan
Abstract:
Ubiquitination is a versatile posttranslational modification mechanism used by eukaryotic cells. The ubiquitin-mediated proteolytic pathway plays a crucial role in the elimination of short-lived regulatory proteins including those that contribute to the cell cycle, cellular signaling, DNA repair, morphogenesis, protein quality control, and transcriptional regulation. The ubiquitin-proteasome pathway involves ubiquitin modification of substrates and sequential degradation by the proteasome. Ubiquitin conjugation is catalyzed by ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2), and ubiquitin ligase (E3). E3 is a scaffold protein that mediates between the ubiquitin-linked E2 and the substrate. E3 is thought to be most directly responsible for substrate recognition. E3 ubiquitin ligases so far identified include members of the HECT and RING-finger protein families. Tripartite motif (TRIM) proteins are characterized by the presence of a RING finger, one or two zinc-binding motifs called B-boxes, and an associated coiled-coil region (RBCC). TRIM family proteins are currently comprised of about 71 members in the human genome. TRIM family proteins are involved in a broad range of biological processes and their alterations often cause diverse pathological conditions such as developmental disorders, neurodegenerative diseases, viral infection and cancers. So far, we have tried to analyze the binding proteins to TRIM proteins comprehensively and have clarified their relationships. In this talk, we focus on topics of TRIM proteins that regulate carcinogenesis and signal transduction.
References:
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