Studies on fertilization of the hagfish and amphioxus

盲鳗和文昌鱼的受精作用很长时间以来都不为人所知，但由于这些动物位于无脊椎动物和脊椎动物之间的边界，因此受精作用很重要。在本项目中，我们在盲鳗（1 -4号）和文昌鱼（5号）中获得了以下结果。1.对精子发生进行了详细研究。研究结果已提交给《生物学通报》。2.将未成熟的雌性和雄性动物用激素如GnRH处理，并将其保存在海中或实验室水槽中。卵在体腔中排卵，有或没有处理。尝试了人工授精。3.首次对精子活力进行了研究。精子活力和精子结构受渗透压的影响。目前正在编写一份介绍结果的手稿，以供出版。4.在顶体反应中获得了有趣的结果。顶体胞吐作用发生在哺乳动物的顶体反应中的许多点上，并且产生顶体过程，如在海洋无脊椎动物的顶体反应中所见。在日本和美国采集的2个种中观察到这些事实。在顶体区域发现肌动蛋白。研究结果已发表在Develop上。增长差异。5.在文昌鱼中，顶体反应是本课题组首次报道的。该反应由钙离子载体离子霉素诱导。顶体囊泡首先在前端打开，形成顶体突。顶体下物质参与了包含丝状结构的突起核心的形成。反应模式与海洋无脊椎动物中所见的非常相似。获得的结果已发表在Zool. Science上。我在Mohri等人编辑的“Spermatology，2nd edition”中回顾了该项目下获得的结果摘要，东京大学出版社.

Fertilization in hagfish and amphioxus has not been known for a long time and is important since the animals are situated in the border between invertebrates and vertebrates. In the present project, we obtained following results in hagfish (no.1-4) and in amphioxus (no.5). 1.Spermiogenesis was investigated in detail. The results are submitted to Biological Bulletin. 2.Pre-mature females and males were treated with hormone such as GnRH and kept under the sea or in a laboratory tank. Eggs were ovulated in the body cavity with or without treatment. Artificial insemination of the eggs was tried. 3.Sperm motility was studied for the first time. Sperm motility and sperm structure were affected by osmolality. A manuscript describing the results is being prepared for publication. 4.We obtained interesting results in the acrosome reaction. Acrosomal exocytosis occurred at many points as seen in the acrosome reaction in mammals, and an acrosomal process was produced as seen in the acrosome reaction in marine invertebrates. These facts were observed in 2 species collected in Japan and U.S.A. Actin was found in the acrosomal region. The results have been published in Develop. Growth Differ. 5.In the amphioxus, the acrosome reaction was for the first time reported by us under this project. The reaction was induced by a Ca ionophore, ionomycin. The acrosomal vesicle first opened at the anterior end, and an acrosomal process was formed. The subacrosomal material participated in formation of the process core that contained filamentous structure. The mode of the reaction was quite similar to that seen in marine invertebrates. The results obtained have been published in Zool. Science.I reviewed summary of the results obtained under this project in "Spermatology, 2nd edition" edited by Mohri et al., The University Tokyo Press.