Molecular mechanism of mitochondrial proteins using ubiquinone as a cofactor

2014 Fiscal Year Final Research Report

• Project/Area Number: 25850081
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Bioorganic chemistry
• Research Institution: Kyoto University
• Principal Investigator: MURAI Masatoshi 京都大学, (連合)農学研究科(研究院), 助教 (80543925)
• Co-Investigator(Renkei-kenkyūsha): KAWAMUKAI Makoto 島根大学, 大学生物資源科学部, 教授 (70186138)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: ユビキノン / Coq10 / 光親和性標識 / ミトコンドリア / 複合体-I

Outline of Final Research Achievements

Ubiquinone (UQ) is thought to diffuse freely in the inner mitochondrial membrane to facilitate electron transfer between the respiratory complexes. Recent studies have focused on physiological importance of mitochondrial Coq10, which is a member of the steroidogenic acute regulatory protein (StAR)-related lipid transfer (START) domain superfamily. To get insights into the role of Coq10, we expressed the recombinant Schizosaccharomyces pombe Coq10 in Escherichia coli membrane, and carried out photoaffinity labeling study using a synthetic UQ probe. Comprehensive biochemical and proteomic analyses revealed that the UQ probe specifically binds to the N-terminus F39-K45 of the Coq10, which corresponds to the ligand-binding pocket in many proteins containing START domain. Our results provide the first exact evidence indicating that Coq10 accommodates UQ in a similar manner with other SATRT domain proteins do.

Free Research Field

生物有機化学