Identification of genes involved in germline sex determination by global screening

• Project/Area Number: 18K19332
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 44:Biology at cellular to organismal levels, and related fields
• Research Institution: Nagoya University
• Principal Investigator: Nishimura Toshiya 名古屋大学, 理学研究科, 助教 (10758056)
• Project Period (FY): 2018-06-29 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000)
• Keywords: 生殖細胞 / ゲノム編集 / メダカ / CRISPR/Cas9

Outline of Final Research Achievements

Germ cells are the only cells that can generate the next generation and produce either sperm and eggs. In this study, a genetic screening system was constructed to elucidate the mechanism of sperm-egg fate decision in germ cells using medaka. First, comparative gene expression analyses were performed between male and female germ cells to narrow down the number of candidate genes. Second, an efficient generation of DNA templates for gRNAs in CRISPR/Cas9 system was established. Third, transgenic lines in which spermatogenesis and oogenesis could be visualized by fluorescence were established. Upon gene knock-out, the phenotype could be easily distinguished by observing alive medaka under a fluorescent microscopy.

Academic Significance and Societal Importance of the Research Achievements

生殖細胞がどのような仕組みで精子あるいは卵になるか（生殖細胞の性決定）は、医学や水畜産学分野において基本的な問題であるにも関わらずほとんど分かっていないのが現状である。メダカを用いた研究で脊椎動物で初めてfoxl3という生殖細胞の性決定遺伝子が同定された。本研究では、foxl3を中心とした生殖細胞の性の仕組みを具体的に明らかにするために、効率的に生殖細胞の性に関わる遺伝子群のスクリーニング可能な実験系を構築した。本手法は生きた個体を用いて簡便に遺伝子の働きを探ることが出来るため、生殖生物学分野の研究だけでなく、生物学分野全般の研究において役立つツールだと考えられる。

Research Products

• [Journal Article] Seasonal changes in NRF2 antioxidant pathway regulates winter depression-like behavior (2020)
  • Author(s): Nakayama T, Okimura K, Shen J, Guh Y-J, Tamai K, Shimada A, Minou S, Okushi Y, Shimmura T, Furukawa Y, Kadofusa N, Sato A, Nishimura T, Tanaka M, Nakayama K, Shiina N, Yamamoto N, Loudon A.S, Nishiwaki-Ohkawa T, Shinomiya A, Nabeshima T, Nakane Y, and Yoshimura T
  • Journal Title: PNAS Volume: - Issue: 17 Pages: 1-10
  • DOI: 10.1073/pnas.2000278117
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Starvation causes female-to-male sex reversal through lipid metabolism in the teleost fish, medaka (Olyzias latipes) (2020)
  • Author(s): Sakae Yuta、Oikawa Akira、Sugiura Yuki、Mita Masatoshi、Nakamura Shuhei、Nishimura Toshiya、Suematsu Makoto、Tanaka Minoru
  • Journal Title: Biology Open Volume: 9 Issue: 4 Pages: 1-12
  • DOI: 10.1242/bio.050054
  • Peer Reviewed / Open Access
• [Journal Article] Novel components of germline sex determination acting downstream of foxl3 in medaka (2019)
  • Author(s): Kikuchi Mariko、Nishimura Toshiya、Saito Daisuke、Shigenobu Shuji、Takada Ritsuko、Gutierrez-Triana Jos? Arturo、Cerd?n Juan Luis Mateo、Takada Shinji、Wittbrodt Joachim、Suyama Mikita、Tanaka Minoru
  • Journal Title: Developmental Biology Volume: 445 Issue: 1 Pages: 80-89
  • DOI: 10.1016/j.ydbio.2018.10.019
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Seasonal regulation of the lncRNA LDAIR modulates self-protective behaviours during the breeding season (2019)
  • Author(s): Nakayama T, Shimmura T, Shinomiya A, Okimura K, Takehana Y, Furukawa Y, Shimo T, Senga T, Nakatsukasa M, Nishimura T, Tanaka M, Okubo K, Kamei Y, Naruse K, Yoshimura T
  • Journal Title: Nature Ecology & Evolution Volume: 3 Pages: 845-852
  • NAID: 120006718405
  • Peer Reviewed
• [Presentation] Germline sex determination by nanos3, a component of germ plasm, in medaka (2018)
  • Author(s): Nishimura T and Tanaka M
  • Organizer: 4th Strategic Meeting for Medaka Research 3rd Regional Fish Meeting
  • Int'l Joint Research