Analysis of cell cycle regulation system by organelle signal.

2014 Fiscal Year Final Research Report

• Project/Area Number: 25840006
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Molecular biology
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: KOBAYASHI Yuki 東京工業大学, 資源化学研究所, 助教 (80644616)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: レトログレードシグナル / DNA複製 / テトラピロール / 植物ホルモン / アブシジン酸

Outline of Final Research Achievements

In plant cells, organelle DNA replication (ODR) is coordinated with nuclear DNA replication (NDR), with ODR preceding NDR during cell cycle progression. We previously reported that the occurrence of ODR is signalled by a tetrapyrrole compound, resulting in the activation of cyclin-dependent kinase and consequent initiation of NDR in red algae C. merolae. However, mechanism of ODR initiation is unknown. But, we previously found that MAPK cascade correlate the ODR initiation. In this study, we aimed to clear the mechanism of ODR initiation. We found that MAPK3 activation is correlated with ODR, this activation induced by light illumination. On the other hand, we found that inhibition of tetrapyrrole synthesis caused ODR inhibition, and this ODR inhibition canceled by exogenous heme addition. These observations suggested that change of light environmental and state of mitochondria were monitored by both MAK3 and intercellular heme accumulation and consequent initiation of ODR.

Free Research Field

植物生理