RESEARCH OVERVIEW Ubiqitin and Ubiquitin-like Protein Modification Besides transcription- and translation-level controls, eukaryotic cells fine-tune functions and physiology of cellular proteins by utilizing various post-translational modifications such as phosphorylation, glycosylation and ubiquitination. Among them, we are interested in ubiquitin- (and ubiquitin-like protein) mediated post-translational modification systems. In addition to ubiquitination, which is well-known for its involvement in protein degradation pathway, we also study on several ubiquitin-like proteins(UBLs) such as SUMO, ISG15, Nedd8 and Ufm1. Our research focus includes identifying substrates and processing enzymes for ubiquitination/deubiquitination or other UBL modifications, and understanding their functions and involvements in cellular processes. We use biochemistry, cell biology and proteomics as the main methodology.