合浦珠母贝卵子发育的超微结构研究

合浦珠母贝卵子发育的超微结构研究 AN ULTRASTRUCTURAL STUDY ON OOGENESIS OF PEARL OYSTER PINCTADA MARTENSII DUNKER 沈亦平 Shen Yiping Zhang Xiyuan 1 first-author 张锡元 1 武汉大学生命科学学院 武汉大学生命科学学院 School of Life Science, Wuhan University School of Life Science, Wuhan University 透射电镜下观察了合浦珠母贝卵子发育过程:卵原细胞被滤泡细胞完全包囊,初级卵原细胞具一明显核仁,胞质内分布少量线粒体,次级卵原细胞核仁消失,成簇的线粒体分布于核膜一侧.卵黄合成前期卵母细胞胞体稍增大,核仁重现,胞质内出现大量管状或泡状膜性小体,此期卵母细胞开始逐渐游离,并自游离端首先出现微绒毛和卵黄膜.卵黄合成期卵母细胞胞体迅速增大,核膜常伸出伪足状突起,胞质内出现较多的线粒体以及结构独特的内质网.此期还可观察到卵母细胞与来源于滤泡细胞的胞外小泡融合的现象,卵黄合成后期胞质内充满大量卵黄粒,脂滴和少量糖元,内质网和线粒体大大减少.另外我们观察到卵巢中残留精子鞭毛的现象,在超微结构水平上证实了合浦珠母贝的性变现象. Ultrastructural features of oogenesis of the pearl oyster, Pinctada martensii Dunker were observed under TEM. Oogonia are wholly surounded by follicle ceils, when they transform into prima- ry cocytes, the follicle cells detach from the apex of the oocyte, the mierovilli and viteUine membrane soon form around the oocyte. Oogonia lack of organelles in cytoplasm besides of some mitoehondrias. Ooeytes at previtellogenesis stage contain a lot of membranous vesicles in cytoplasm, at vitellogenesis stage, well developed Golgi complex and RER with paralled lamellas present in cytoplasm. Golgi vesi- cles, RER, mitochondrias and multiple vesicles are involved in yolk granules formation. Yold synthe- sis appears to occure by both autosynthetic and heterosynthetic process, the follicle cells take part in the synthesis of yold precursor, the yolk precursor are transported into oocyte by pinocytosis and fu- sion. We also discoved that the flagellum of sperm remain in the ovary ,it indicated that sex reverse had once happened. 合浦珠母贝 卵子发生 超微结构 Pinctada martensii Dunker oogencsis ultrastructure Q953.1;Q954.432 国家自然科学基金(61672102);广西壮族自治区地方重大项目资助的课题 1993-05-01 2021-04-01 5