生物機能利用研究部門

動物生殖機能制御ユニット

役割

動物生殖機能制御ユニットでは、従来からの繁殖技術だけでは対応できない種々の課題に対応するため、生殖細胞・初期胚・体細胞の新たな利用・制御技術の開発を目指しています。特に、家畜の新しい保存・増殖システムの確立、精子機能異常による低受胎の発生機序の解析、および免疫を利用した動物の不妊化誘起技術の開発に重点をおいて、研究を進めています。

主な研究テーマ

家畜の新しい保存・増殖システムの確立

血友病モデルブタのように組換えモデルブタでは、幼若期の損耗が原因で次の世代が得られない事例が多くあり、次世代を生産できる新しい増殖手法の確立が望まれています。また、海外悪性伝染病(口蹄疫など)の侵入によって在来ブタの消滅の危険性もあります。さらに、途上国のように十分な施設がない状況で遺伝資源を保存するためには、生殖細胞を簡便に保存できる手法の開発も必要です。そこで、超低温保存、異種間移植および顕微授精を組み合わせて、幼若動物の精巣組織から個体を再成する画期的な家畜の増殖システムの確立を進めています。


新しい家畜増殖システムの確立

超低温保存、異種間移植、体外培養および顕微授精を組み合わせて、胎子または新生子の精巣から次世代を生産できる新しい増殖システムの確立を目指しています。このシステムを応用によって、組換えモデルブタあるいは希少な在来ブタの遺伝情報の保存が期待できます。


新しいシステムによって生産されたブタ精子

精子機能異常による低受胎の発生機序の解析

家畜(特にウシ)の低受胎は長期間にわたり全世界的に進行している深刻な問題です。これまで、雌動物の原因の解明が主で、雄動物の関連については調べられてきませんでした。そこで、精子機能異常に起因する低受胎について、モデル動物(マウス)を用い遺伝解析等によってその発生機序の解明を行っています。さらに、低受胎雄家畜の交配前診断法の開発も進めています。

免疫を利用した不妊化誘起技術の開発

近年の野生動物の食害の増加に対応するため、新たな個体数の管理手法の開発が求められています。そこで、ラットおよびヤギ等を用い、精子などの生殖細胞を抗原としたワクチン接種によって、生殖細胞の機能を制御し不妊を誘起する手法の開発を目指しています。


メンバー

メンバーの主要成果

(原著論文) (過去5年以内に発表したもの)

  • Kaneko H, Kikuchi K, Noguchi J. (2016) Growth and fertilization of porcine fetal oocytes grafted under the renal capsules of nude mice. Theriogenology, in press.
  • Kikuchi K, Kaneko H, Nakai M, Somfai T, Kashiwazaki N, Nagai T. (2016) Contribution of in vitro systems to preservation and utilization of porcine genetic resources. Theriogenology 86(1), 170-175.
  • Men NT, Kikuchi K, Furusawa T, Dang-Nguyen TQ, Nakai M, Fukuda A, Noguchi J, Kaneko H, Viet Linh N, Xuan Nguyen B, Tajima A. (2016) Expression of DNA repair genes in porcine oocytes before and after fertilization by ICSI using freeze-dried sperm. Anim Sci J, in press.
  • Nakai M, Ito J, Kashiwazaki N, Men NT, Tanihara F, Noguchi J, Kaneko H, Onishi A, Kikuchi K. (2016) Treatment with protein kinase C activator is effective for improvement of male pronucleus formation and further embryonic development of sperm-injected oocytes in pigs. Theriogenology 85(4), 703-708.
  • Somfai T, Men NT, Noguchi J, Kaneko H, Kashiwazaki N, Kikuchi K. (2015) Optimization of cryoprotectant treatment for the vitrification of immature cumulus-enclosed porcine oocytes: comparison of sugars, combinations of permeating cryoprotectants and equilibration regimens. J Reprod Dev 61(6), 571-579.
  • Somfai T, Yoshioka K, Tanihara F, Kaneko H, Noguchi J, Kashiwazaki N, Nagai T, Kikuchi K. (2014) Generation of live piglets from cryopreserved oocytes for the first time using a defined system for in vitro embryo production. PLoS One 9(5), e97731.
  • Kaneko H, Kikuchi K, Tanihara F, Noguchi J, Nakai M, Ito J, Kashiwazaki N. (2014) Normal reproductive development of pigs produced using sperm retrieved from immature testicular tissue cryopreserved and grafted into nude mice. Theriogenology 82(2), 325-331.
  • Nakai M, Ozawa M, Maedomari N, Noguchi J, Kaneko H, Ito J, Onishi A, Kashiwazaki N, Kikuchi K. (2014) Delay in cleavage of porcine embryos after intracytoplasmic sperm injection (ICSI) shows poorer embryonic development. J Reprod Dev 60(3), 256-269.
  • Misumi K, Hirayama Y, Suzuki M, Nakai M, Kaneko H, Noguchi J, Kikuchi K. (2014) Production of Middle White piglets after transfer of embryos produced in vitro. J Reprod Dev 60(3), 246-249.
  • Tanihara F, Nakai M, Men NT, Kato N, Kaneko H, Noguchi J, Otoi T, Kikuchi K. (2014) Roles of the zona pellucida and functional exposure of the sperm-egg fusion factor 'IZUMO' during in vitro fertilization in pigs. Anim Sci J 85(4), 395-404.
  • Men NT, Kikuchi K, Nakai M, Fukuda A, Tanihara F, Noguchi J, Kaneko H, Linh NV, Nguyen BX, Nagai T, Tajima A. (2013) Effect of trehalose on DNA integrity of freeze-dried boar sperm, fertilization, and embryo development after intracytoplasmic sperm injection. Theriogenology 80(9), 1033-1044.
  • Egerszegi I, Somfai T, Nakai M, Tanihara F, Noguchi J, Kaneko H, Nagai T, Ratky J, Kikuchi K. (2013) Comparison of cytoskeletal integrity, fertilization and developmental competence of oocytes vitrified before or after in vitro maturation in a porcine model. Cryobiology 67(3), 287-292.
  • Kaneko H, Nakai M, Tanihara F, Noguchi J, Kikuchi K. (2013) Improved developmental ability of porcine oocytes grown in nude mice after fusion with cytoplasmic fragments prepared by centrifugation: a model for utilization of primordial oocytes. Theriogenology 80(8), 887-892.
  • Viet Linh N, Kikuchi K, Nakai M, Tanihara F, Noguchi J, Kaneko H, Dang-Nguyen TQ, Men NT, Van Hanh N, Somfai T, Nguyen BX, Nagai T, Manabe N. (2013) Fertilization ability of porcine oocytes reconstructed from ooplasmic fragments produced and characterized after serial centrifugations. J Reprod Dev 59(6), 549-56.
  • Kaneko H, Kikuchi K, Nakai M, Somfai T, Noguchi J, Tanihara F, Ito J, Kashiwazaki N. (2013) Generation of live piglets for the first time using sperm retrieved from immature testicular tissue cryopreserved and grafted into nude mice. PLoS One 8(7):e70989.
  • Misumi K, Hirayama Y, Suzuki M, Nakai M, Noguchi J, Kaneko H, Kikuchi K. (2014) Effects of the estrous cycle on the efficacy of oocyte collection and in vitro embryo production in Duroc-breed. Anim Sci J 85(2), 112-117.
  • Tanihara F, Nakai M, Kaneko H, Noguchi J, Otoi T, Kikuchi K. (2013) Evaluation of zona pellucida function for sperm penetration during in vitro fertilization in pigs. J Reprod Dev 59(4), 385-392.
  • Somfai T, Nakai M, Tanihara F, Noguchi J, Kaneko H, Kashiwazaki N, Egerszegi I, Nagai T, Kikuchi K. (2013) Comparison of ethylene glycol and propylene glycol for the vitrification of immature porcine oocytes. J Reprod Dev 59(4), 378-384.
  • Noguchi J, Nakai M, Kikuchi K, Kaneko H, Imaeda N. (2013) Early regression of spermatogenesis in boars of an inbred Duroc strain caused by incident orchitis/epididymo-orchitis. J Reprod Dev 59(3), 273-281.
  • Kaneko H, Kikuchi K, Nakai M, Tanihara F, Noguchi J, Noguchi M, Ito J, Kashiwazaki N. (2012) Normal reproductive development of offspring derived by intracytoplasmic injection of porcine sperm grown in host mice. Theriogenology 78(4), 898-906.
  • Kikuchi K, Nakai M, Kashiwazaki N, Kaneko H. (2011) Xenografting of gonadal tissues into mice as a possible method for conservation and utilization of porcine genetic resources. Anim Sci J 82(4), 495-503.
  • Viet Linh N, Kikuchi K, Nakai M, Noguchi J, Kaneko H, Dang-Nguyen TQ, Maedomari N, Nguyen BX, Nagai T, Manabe N. (2011) Improvement of porcine oocytes with low developmental ability after fusion of cytoplasmic fragments prepared by serial centrifugation. J Reprod Dev 57(5), 620-626.
  • Nakai M, Ito J, Sato K, Noguchi J, Kaneko H, Kashiwazaki N, Kikuchi K. (2011) Pre-treatment of sperm reduces success of ICSI in the pig. Reproduction 142, 285-293.
  • Nakai M, Kashiwazaki N, Ito J, Maedomari N, Ozawa M, Shino M, Noguchi J, Kaneko H, Kikuchi K. (2011) Factors affecting fertilization and embryonic development during intracytoplasmic sperm injection in pigs. J Reprod Dev 57(2), 183-187.
  • Okada K, Kimura M, Moriyama Y, Nakai M, Kikuchi K, Kaneko H, Kunieda T, Baba T, Noguchi J. (2011) Expression analysis of MIF4GD in the rat testis. J Reprod Dev 57(2), 256-261
  • Kawai Y, Noguchi J, Akiyama K, Takeno Y, Fujiwara Y, Kajita S, Tsuji T, Kikuchi K, Kaneko H, Kunieda T. (2011) A missense mutation of the Dhh gene is associated with male pseudohermaphroditic rats showing impaired Leydig cell development. Reproduction 141(2), 217-225.