Degradation of old tRNA and metabolisim of modified nucleotides

2015 Fiscal Year Final Research Report

• Project/Area Number: 26650009
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Molecular biology
• Research Institution: University of Hyogo
• Principal Investigator: Yoshihisa Tohru 兵庫県立大学, 生命理学研究科, 教授 (60212312)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: tRNA / 分解 / 非対称分裂

Outline of Final Research Achievements

I picked up tRNA, a long-lived class of RNAs, to examine whether eukaryotic cells performing asymmetric cell division deliver 'wounded' tRNA molecules asymmetrically like aggregated proteins, and how modified nucleotides derived from degraded tRNA are processed, and tried to establish experimental systems in yeast. I found that 'old' yeast cells from the view of the replicative life span do not show significant difference from young cells in their tRNA localization. I also isolated temperature-sensitive tRNA mutants that lead transient increase of modified nucleotides in amount by degradation of the tRNA molecules and allow analysis of dynamics of the modified nucleotides. Finally, I analyzed molecular mechanism of nuclear import of tRNA, which strongly affects intracellular localization of tRNA, and found that one of the yeast cytosolic Hsp70s, Ssa2p, is a transport carrier of tRNA in the nuclear import.

Free Research Field

分子生物学・細胞生物学