Analysis of nucleolar RNA-protein network that regulates mitotic chromosome dynamics

2016 Fiscal Year Final Research Report

• Project/Area Number: 25290064
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Genome biology
• Research Institution: University of Tsukuba
• Principal Investigator: KIMURA Keiji 筑波大学, 生命環境系, 准教授 (50332268)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: 分裂期 / 染色体 / 核小体 / RNA / Aurora B / NOL11 / リン酸化

Outline of Final Research Achievements

We analyzed the function of NOL11 that were identified as the factor that were involved in mitosis from large scale siRNA screening. NOL11 formed complex with WDR43 and Cirhin, and associated with periphery of mitotic chromosomes. We found that NOL11　KD caused mitotic defects such as aberrant mitotic chromosome alignment and a delay in mitotic progression. Delay in mitotic progression was induced by inhibition of cdc2 kinase due to increased inhibitory phosphorylation of cdc2 kinase at Tyr15. In addition to the mitotic phenotype, NOL11 KD reduced rRNA transcription and caused nucleolar disruption during interphase. Interestingly, delay in mitotic progression was also observed when nucleolar disruption during interphase was induced by other methods. Furthermore, the defects was ameliorated when nucleolar disruption during interphase was suppressed. Thus, nucleolar integrity during interphase is required for proper mitotic progression.

Free Research Field

生化学