Tsukamoto Mariko, Hiyama Erina, Hirotani Karen, Gotoh Takafumi, Inai Tetsuichiro, Iida Hiroshi
Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Fukuoka, Japan.
Kuju Agriculture Research Center, Kyushu University, Oita, Japan.
Mol Reprod Dev. 2017 Jan;84(1):30-43. doi: 10.1002/mrd.22763. Epub 2016 Dec 27.
Tektins (TEKTs) are filamentous proteins associated with microtubules in cilia, flagella, basal bodies, and centrioles. Five TEKTs (TEKT1, -2, -3, -4, and -5) have been identified as components of mammalian sperm flagella. We previously reported that TKET1 and -3 are also present in the heads of rodent spermatozoa. The present study clearly demonstrates that TEKT2 is present at the acrosome cap whereas TEKT3 resides just beneath the plasma membrane of the post-acrosomal region of sperm heads in unactivated bull spermatozoa, and builds on the distributional differences of TEKT1, -2, and -3 on sperm heads. We also discovered that hyperactivation of bull spermatozoa by cell-permeable cAMP and calyculin A, a protein phosphatase inhibitor, promoted translocation of TEKT3 from the post-acrosomal region to the equatorial segment in sperm heads, and that TEKT3 accumulated at the equatorial segment is lost upon acrosome reaction. Thus, translocation of TEKT3 to the equatorial segment may be a capacitation- or hyperactivation-associated phenomenon in bull spermatozoa. Mol. Reprod. Dev. 84: 30-43, 2017. © 2016 Wiley Periodicals, Inc.
纤毛蛋白（TEKTs）是与纤毛、鞭毛、基体和中心粒中的微管相关的丝状蛋白。已确定五种纤毛蛋白（TEKT1、-2、-3、-4和-5）是哺乳动物精子鞭毛的组成部分。我们之前报道过，TEKT1和-3也存在于啮齿动物精子的头部。本研究清楚地表明，TEKT2存在于顶体帽处，而在未激活的公牛精子中，TEKT3位于精子头部顶体后区域质膜下方，并基于TEKT1、-2和-3在精子头部的分布差异展开研究。我们还发现，通过细胞可渗透的环磷酸腺苷（cAMP）和蛋白磷酸酶抑制剂花萼海绵诱癌素A使公牛精子超激活，会促使TEKT3从顶体后区域转移至精子头部的赤道段，并且在顶体反应时，积累在赤道段的TEKT3会消失。因此，TEKT3向赤道段的转移可能是公牛精子中与获能或超激活相关的现象。《分子生殖与发育》84: 30 - 43, 2017。© 2016威利期刊公司。
