Hatching of an estuarine crab : characterization, activity, and putative role of a caseinolytic protease

河口蟹的孵化：酪蛋白分解酶的特征、活性和假定作用

• 批准号: 08833009
• 负责人: SAIGUSA Masayuki
• 金额: $ 1.54万
• 依托单位: Okayama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08833009/
• 关键词: Marine crustanceans; Hatching; Caseinolytic protease; Activity and characterization; Ultrastructure; Embryonic envelope; 吸水; 活性; 生化学的性質; 卵浮化; 海産カニ類; 活性物質の精製; OHSS(胚脱落誘発物質); カゼインを分解するプロラアーゼ; 酵素

The zoeas of an estuarine crab Sesarma haematocheir (akate-gani) hatch synchronously within 0.5 - 1 h from a female. Three aspects of hatching were studied : caseinolytic activity, morphological changes of the embryonic envelope structure, and environmental factors. Hatch water (i.e., the filtered medium in whcih zoeas have hatched) contains a caseinolytic protease, and the molecular weight of this protease was estimated on gel filtration. Transmission electron microscopy shows that the envelope (1.8 mum thick) is composed of three distinct layrs : an outer (E1), thick middle (E2), and thin inner (E3) layr. The outer two layrs, that are structurally the main components of the envelope, were not morphologically altered during hatching, but the inner layr (E3) was clearly altered between 11 h and 3 h before hatching, suggesting its digestion. The assay with isolates of the embryonic envelopes and morphological observations also suggested that the envelope is digested by the hatch water. The time of hatching was strongly affected by low water temperatures, and their effects were much stronger to the embryos detached from the female than female-attached embryos. Salinity was ineffective. Mechanisms of hatching based on the digestion of this (E3) layr has been discussed.

河口蟹（akate-gani）的卵在0.5 - 1小时内从雌性同步孵化。从酪蛋白溶解活性、胚包膜结构形态变化和环境因素三个方面对孵化过程进行了研究。孵化水（即动物孵化的过滤介质）含有酪蛋白水解蛋白酶，该蛋白酶的分子量是通过凝胶过滤估计的。透射电子显微镜显示，包膜（1.8 mm厚）由三层不同的层组成：外层（E1），厚中层（E2）和薄内层（E3）。外两层是包膜的主要结构成分，在孵化过程中形态未发生变化，但在孵化前11 ~ 3 h，内层（E3）发生了明显的变化，表明其被消化。胚包膜分离物的测定和形态观察也表明胚包膜被孵化水消化。低水温对孵化时间的影响较大，对离体胚的影响大于附着体胚的影响。盐度无效。讨论了基于该（E3）层溶出的孵化机理。

项目成果

M.Saigusa: "Hatching and its control by the circatidal clock" Proceedings of Arthropodan Emb.Soc.32. 1-23 (1997)

M.Saigusa：“孵化及其生物钟的控制”节肢动物 Emb.Soc.32 论文集。

M.Saigusa: "Hatching and its control by the circatidal clock" Proceedings of Atrhropodan Emb.Soc.32. 1-23 (1997)

M.Saigusa：“孵化及其生物钟的控制”Atrropodan Emb.Soc.32 论文集。

K.Oishi, M.Saigusa: "Nighttime emergence patterns in benthic and・・・" J.Oceanography. 53. 611-621 (1997)

K.Oishi、M.Saigusa：“底栖生物的夜间出现模式和……”J.Oceanography 53. 611-621 (1997)。

Saigusa.M.: "Hatching and its contool of・・・・" Proceedings of Arthropodan Embryol.Soc.Japan. 32(in press). (1997)

Saigusa.M.：“孵化及其控制……”Proceedings of Arthropodan Embryol.Soc.Japan 32（出版中）。

M.Saigusa: "The circatidal clock in an estuarine crab." Benthos Research. 52. 21-33 (1997)

M.Saigusa：“河口蟹的生物钟。”