Study on the germ cell migration and sex differentiation in domestic chicken

• Project/Area Number: 17K08039
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Animal production science
• Research Institution: University of Tsukuba
• Principal Investigator: TAJIMA Atsushi 筑波大学, 生命環境系, 教授 (40207030)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2017: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: ニワトリ / 始原生殖細胞 / 分化 / RNA-seq / 多能性 / 減数分裂 / 始原生殖細胞(PGCs / 生殖巣生殖細胞(GGCs) / 多能性関連遺伝子群 / 生殖細胞特異的遺伝子群 / 性分化 / 生殖巣生殖細胞 / MACS / 始原生殖細胞(PGCｓ) / 生殖巣

Outline of Final Research Achievements

Attempts have been made to produce germ line chimera (GLC) by transferring germline stem cells (gSCs) from 2-9 days-old chick embryos. GLC was produced in all cases except when gSCs from female 9 days-old embryos have been transferred to the recipients.In the present study, therefore, RNA was extracted from gSCs and RNA-seq was conducted to examine the temporal changes of mRNA pattern of gSCs associated with early embryonic development.
The results indicate that 1) expression of genes related to pluripotency have been down-regulated by 5 days in both sexes. 2) expression of genes related to germ cells were down-regulated throughout the examination periods 3) No significant differences in the expression of genes related to meiosis in both sexes.

Academic Significance and Societal Importance of the Research Achievements

鳥類においては、受精卵の長期保存ができないことから、生殖幹細胞(gSCs)を利用した遺伝資源の保存方法の開発が進められてきた。これまでに、孵卵2日～9日ニワトリ胚由来の生殖系列幹細胞(gSCs)を用いて生殖系列キメラの(GLC)作製を試みた結果、孵卵9日の雌胚由来のgSCsを用いた場合を除きGLCが作製された。これは、胚の発生が進むのに伴い生殖細胞の分化が進むためであると考え、生殖細胞からRNAを抽出してRNA-seqを行った結果、胚の発生に伴いrGCsにおけるｍRNAの発現パターンに変化が生じることが明らかになった。

Research Products

• [Presentation] Potentials of physiological parameters to elucidate the internal development of early chick embryos (2020)
  • Author(s): Takehara M, Kishi M, Asano A, Tajima A.
  • Organizer: Poultry Science Meeting July 20-22,2020.
  • Int'l Joint Research
• [Presentation] Gene expression of gonadal germ cells (GGCs) in domestic chicken. (2020)
  • Author(s): Kishi M, Takehara M, Onuma M, Nakajima N, Asano A, Tajima A.
  • Organizer: World Poultry Congress, Aug16-20, 2020, Paris.(suspended)
  • Int'l Joint Research
• [Presentation] ニワトリ初期胚の発生に伴う血液成分の変化 (2019)
  • Author(s): 竹原稔・貴志雅哉・浅野敦之・田島淳史
  • Organizer: 日本家禽学会大会, 2019年9月19日 岩手大学
• [Presentation] ニワトリ初期胚の発生に伴う形態的変化と生理的変化の関係 (2018)
  • Author(s): 竹原稔、貴志雅哉、浅野敦之、石川尚人、田島淳史
  • Organizer: 日本家禽学会
• [Presentation] 免疫磁気細胞分離法(MACS法)を用いたニワトリGGCsの単離 (2018)
  • Author(s): 貴志雅哉、竹原稔、浅野敦之、石川尚人、田島淳史
  • Organizer: 日本家禽学会