Sex determination caused by failure of X-chromosome dosage compensation in Drosophila germline

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K14739
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 44040:Morphology and anatomical structure-related
• Research Institution: University of Tsukuba
• Principal Investigator: Ryoma Ota 筑波大学, 生存ダイナミクス研究センター, 研究員 (00647969)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 生殖系列 / 性決定 / 遺伝子量補償 / ショウジョウバエ

Outline of Final Research Achievements

This study aims to clarify the cell-autonomous mechanism of sex determination in Drosophila germline. We have previously found that dosage compensation equalizing X-linked gene expression between the sexes is absent in primordial germ cells (PGCs). Here, we show that hyperactivation of X-linked genes is induced in XY (male) PGCs by overexpression of the essential components of the MSL complex is responsible for dosage compensation in Drosophila. Furthermore, we show a possibility that hyperactivation of X-linked genes induces feminization in XY PGCs. These findings strongly suggest that cell-autonomous sex determination in the germline is resulted from the biased expression of X-linked genes caused by absence of dosage compensation.

Free Research Field

生殖生物学

Academic Significance and Societal Importance of the Research Achievements

本研究から、未だあらゆる種で十分に明らかになっていない生殖系列自律的な性決定機構に関する重要な知見が得られた。生殖系列自律的な性決定機構は、ショウジョウバエのみならず、ヒトやマウス、メダカなど種を超えて存在することが明らかになりつつある。したがって、本研究の成果は、動物に普遍的な生殖系列の性決定メカニズムを理解するうえで重要な基盤となる。また、本研究で得られた成果は、体細胞系列と生殖系列の性の不一致により起こる不妊の原因究明のための重要な基盤にもなると考えられる。