Mechanism of nuclear segregation in the methylotrophic yeast Hansenula polymorpha

2014 Fiscal Year Final Research Report

• Project/Area Number: 24570214
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Cell biology
• Research Institution: Osaka University
• Principal Investigator: MAEKAWA Hiromi 大阪大学, 工学(系)研究科(研究院), 寄附講座准教授 (80399683)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 酵母 / 細胞周期 / 微小管 / 接合型 / メタノール資化酵母

Outline of Final Research Achievements

The methylotrophic yeast Hansenula polymorpha was established as a model system. Towards this end, I first investigated the previously uncharacterized mating type determination system and the mechanism of self-fertility, and revealed a novel mating type switching system where only one of two mating type loci is transcriptionally active and the chromosomal inversion of their intervening region causes the switching of the mating type identity. This chromosomal inversion-based mechanism represents a novel form of mating type switching that requires only two MAT loci.
I also investigated the regulation of nuclear segregation. In H. polymorpha, unlike in other budding yeast, the nuclear position is not tightly regulated in early stages of the cell cycle, which is due to the poor function of cytoplasmic microtubules. Microscopic analyses of spindle pole bodies (SPB) suggested the structure and function of the cytoplasmic side of SPB is cell cycle regulated.

Free Research Field

細胞生物学