毁灭泰泽球虫(Tyzzeria perniciosa)内生发育的超微结构研究 4.大配子发育与卵囊壁形成

ULTRASTRUCTURAL STUDIES ON THE ENDOGENOUS DEVELOPMENT OF TYZZERIA PERNICIOSA,A COCCIDIAN PARASITE OF PEKINDUCK 4.MACROGAMETOGENESIS AND FORMATION OF OOCYST

毁灭泰泽球虫的大配子是在含有泡内小管的带虫空泡中发育。成囊颗粒Ⅰ在大配子的细胞基质中发育,而成囊颗粒Ⅰ则形成于内质网之嵴内。少数多膜小体见于年轻大配子的细胞质浅层。成熟大配子含有大量的多糖颗粒、少数电子半透明小泡、内质网、线粒体和小管。合子外层膜的膨胀和分离标志着卵囊壁形成的开始。成囊颗粒Ⅰ的物质通过分子渗透过程在合子表面沉积,形成外层。当外层从合子表面分离之后,成囊颗粒Ⅱ的内容物在合子限制膜下累积成层。内层的形成可能是要通过多层物质的分泌与融合的连续过程。粗面内质网在成囊颗粒Ⅱ物质的转运,以及新膜的分离和形成中均起着重要的作用。成熟的卵囊壁由三层组成,分别称为外周膜、外层和内层。

The macrogamete of T.perniciosa developed in parasitophorous vacuole, usually containning a set of intra-vacuolar tubules.The WFB1 was formed in the cytoplasmic matrix of macrogamete,Whereas the WFB2 was within the cisternae of the endoplasmic reticulum.A few bits of multimembranous bodies were found in the peripheral part of cytoplasm of young macrogamete.The mature macrogamete possessed a great many polysaccharide granules,endo- plasmic reticula,mitochondria,canaliculi and a few of electron translucent vacuoles.The elevation and separation of the outer layer membranes of the zygote revealed the initiation of oocyst wall formation.The material of WFB1 deposited the outer layer on the zygote surface by the process of molecular permeation.The contents of WFB2 accumulated to form a layer beneath the limiting membrane.The complete inner layer might be formed by the sequential processes of secretion and coalescence of a multilaminar substance.The mature oocyst wall consisted of three layers,namely,an outermost periphery mem- brane,an outer layer and an inner layer.