Stanley H P, Lambert C C
J Morphol. 1985 Nov;186(2):223-36. doi: 10.1002/jmor.1051860207.
Sertoli cells in the ratfish entirely surround a clone of spermatids to form a spermatocyst. As spermiogenesis proceeds within the cyst cavity, the acrosome areas become apposed to the Sertoli cell plasma membrane lining the spermatocyst. The spermatids elongate and are gathered into an increasingly compact bundle oriented with acrosomal tips directed toward the Sertoli cell base. As all acrosome areas move closer together, Sertoli cell microfilaments oriented parallel to the long spermatid axis appear and increase in concentration. Actin and myosin were demonstrated in the microfilament area with fluorescent antibodies and NBD-Phallacidin. Simultaneously, endocytosis of Sertoli cell membrane between spermatid attachment sites removes the intervening membrane and allows the latter sites to approach each other. Sertoli cell endocytosis is spatially and temporally related to a unique projection at the basal rim of each acrosome. During midspermiogenesis, structured intercellular material appears between the Sertoli cell and the acrosomal region of each spermatid. Its periodicity is closely related to periodic arrangement of Sertoli cell actin and material within the spermatids. These attachment sites move together upon endocytosis, gathering a clone of spermatids into a closely packed bundle.
银鲛的支持细胞完全包围一群精子细胞以形成一个精子囊肿。随着精子发生在囊肿腔内进行，顶体区域与衬于精子囊肿的支持细胞质膜相贴。精子细胞伸长并聚集成一个越来越紧密的束，顶体尖端朝向支持细胞基部排列。当所有顶体区域靠得更近时，平行于精子细胞长轴排列的支持细胞微丝出现并浓度增加。用荧光抗体和NBD-鬼笔环肽在微丝区域证实了肌动蛋白和肌球蛋白。同时，支持细胞膜在精子细胞附着位点之间的内吞作用去除了中间的膜，并使后者的位点彼此靠近。支持细胞内吞作用在空间和时间上与每个顶体基部边缘的一个独特突起相关。在精子发生中期，支持细胞与每个精子细胞的顶体区域之间出现有结构的细胞间物质。其周期性与支持细胞肌动蛋白的周期性排列以及精子细胞内的物质密切相关。这些附着位点在内吞作用时一起移动，将一群精子细胞聚集成一个紧密排列的束。
