piRNA biogenesis pathway in mouse spermatogenesis

2015 Fiscal Year Final Research Report

• Project/Area Number: 24370074
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Molecular biology
• Research Institution: Osaka University
• Principal Investigator: Miyagawa Satomi 大阪大学, 医学(系)研究科(研究院), 特任講師(常勤) (90291153)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: piRNA / 小分子RNA / 精子形成 / レトロトランスポゾン / ミトコンドリア / 生殖顆粒

Outline of Final Research Achievements

piRNA (PIWI interacting RNA) is a germ cell-specific small RNA in whose biogenesis PIWI (P element wimpy testis) family proteins play crucial roles. MILI (mouse Piwi like), one of the mouse PIWI family members, is indispensable for the piRNA production, DNA methylation of retrotransposons through the piRNA, and spermatogenesis. To analyze the molecular function of MILI in piRNA biogenesis, we utilized germline stem cells (GS cells), which are derived from testicular stem cells and possess spermatogonial phenotype. We found that glycerol-3-phosphate acyltransferase 2 (GPAT2), a mitochondrial outer membrane protein for lysophosphatidic acid, bound to MILI and that gene knockdown of GPAT2 brought about the impaired piRNA production in GS cells. GPAT2 is not only one of the MILI bound proteins but also a protein essential for the primary piRNA biogenesis. In addition, MVH (mouse vasa homologues) helicase activity is also indispensable for piRNA production and spermatogenesis.

Free Research Field

発生分子生物学