Functional analysis of BRCA genes and searching for molecular partner for synthetic lethality.

2014 Fiscal Year Final Research Report

• Project/Area Number: 24300328
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Tumor biology
• Research Institution: Tokyo Medical and Dental University
• Principal Investigator: MIKI Yoshio 東京医科歯科大学, 難治疾患研究所, 教授 (10281594)
• Co-Investigator(Kenkyū-buntansha): NAKANISHI Akira 東京医科歯科大学, 難治疾患研究所, 准教授 (50321790) ; TAKENAKA Katsuya 東京医科歯科大学, 難治疾患研究所, 助教 (20378706)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 乳がん / BRCA2 / 合成致死 / 化合物ライブラリー

Outline of Final Research Achievements

We have reported the potential synthetic lethality relationships between BRCA2 deficiency and paclitaxel (PTX). To date, PTX treatment of BRCA2-siRNA knockdown cells has been found to result in a significant increase in microtubule polymer mass. To investigate whether the BRCA2 protein forms the microtubule cytoskeleton complex, we performed immunoprecipitation experiments using anti-BRCA2 antibody. Analysis of the immunoprecipitate by mass spectrometry identified the microtubule-associated proteins (MAP2, MAP4, and Tau) that directly bind microtubules to promote microtubule stabilization. Furthermore, a cell-based tubulin polymerization assay following the treatment of the siRNA knockdown of BRCA2 revealed microtubule stabilization by the effect of MAP4. In this study, we identified MAP4 as a new binding partner of BRCA2, suggesting that a synergistic effect of PTX and MAP4 on tubulin assembly contributes to microtubule stabilization.

Free Research Field

分子腫瘍学