Kobayashi Toshihiro, Amemiya Kazue, Takeuchi Kana, Tsujioka Tomomi, Tominaga Keiichiro, Hirabayashi Masumi, Ishikawa Hajime, Fukui Yutaka, Hochi Shinichi
Faculty of Textile Science and Technology, Shinshu University, Ueda, Nagano 386-8567, Japan.
Zygote. 2006 Feb;14(1):45-51. doi: 10.1017/S0967199406003522.
Using an interspecies microinsemination assay with bovine oocytes, it was examined whether centrosomes of Antarctic minke whale spermatozoa function as the microtubule-organizing centre (MTOC). Bull and rat spermatozoa were used as positive and negative controls, respectively. Vitrified-warmed bovine mature oocytes were subjected to immunostaining against alpha-tubulin 4-6 h after intracytoplasmic injection (ICSI) of 5 mM dithiothreitol-treated spermatozoa. Aster formation occurred from whale spermatozoa (33%) and bull spermatozoa (33%), but very little from rat spermatozoa (3%). Activation treatment for the microinseminated oocytes with 7% ethanol + 2 mM 6-dimethylaminopurine resulted in a similar proportion of oocytes forming a whale sperm aster (35% vs 27% in the non-treated group; 4 h after ICSI) but a significantly larger aster (ratio of aster diameter to oocyte diameter, 0.57 vs 0.30 in the non-treated group). These results indicate that the centrosome introduced into bovine oocytes by whale spermatozoa contributes to the MTOC and that assembly of the microtubule network is promoted by oocyte activation.
利用牛卵母细胞进行种间显微授精试验，研究了南极小须鲸精子的中心体是否作为微管组织中心（MTOC）发挥作用。分别使用公牛和大鼠精子作为阳性和阴性对照。对经5 mM二硫苏糖醇处理的精子进行胞浆内注射（ICSI）后4 - 6小时，对玻璃化复温的牛成熟卵母细胞进行α - 微管蛋白免疫染色。鲸精子（33%）和公牛精子（33%）均可形成星体，但大鼠精子形成星体的比例极低（3%）。用7%乙醇 + 2 mM 6 - 二甲基氨基嘌呤对显微授精的卵母细胞进行激活处理，形成鲸精子星体的卵母细胞比例相似（ICSI后4小时，处理组为35%，未处理组为27%），但星体明显更大（星体直径与卵母细胞直径之比，处理组为0.57，未处理组为0.30）。这些结果表明，鲸精子引入牛卵母细胞的中心体有助于形成微管组织中心，并且卵母细胞激活可促进微管网络的组装。
