Scarlett C J, Lin M, Aitken R J
Cooperative Research Centre for Conservation and Management of Marsupials, School of Biological and Chemical Sciences, The University of Newcastle, NSW, Australia.
J Anat. 2001 Jan;198(Pt 1):93-101. doi: 10.1046/j.1469-7580.2001.19810093.x.
In the tammar wallaby (Macropus eugenii), post-testicular acrosomal shaping involves a complex infolding and fusion of the anterior and lateral projections of the scoop-shaped acrosome into a compact button-like structure occupying the depression on the anterior end of the sperm nucleus. The present study has generated cytochemical and histological evidence to demonstrate that the occurrence of actin filaments (F-actin, labelled by Phalloidin-FITC) in the acrosome of tammar wallaby spermatozoa is temporally and spatially associated with the process of acrosomal shaping in the epididymis, through a pool of monomeric actin (G-actin, labelled by Rh-DNase I) present in the acrosome throughout all stages of epididymal maturation. F-actin was not detected in the acrosome of testicular spermatozoa, but was found in the infolding and condensing acrosome of caput and corpus epididymal spermatozoa. When the spermatozoa completed acrosome shaping in the cauda epididymidis, F-actin disappeared from the acrosomal area. The strong correlation between the occurrence of F-actin and the events of acrosomal shaping suggested that the post-testicular shaping of the acrosome might depend on a precise succession of assembly and disassembly of F-actin within the acrosome as the spermatozoa transit the epididymis. Thus, actin filaments might play a significant role in the acrosomal transformation, as they are commonly involved in morphological changes in somatic cells.
在帚尾岩袋鼠（Macropus eugenii）中，睾丸后顶体塑形涉及勺状顶体的前部和侧向突起复杂的内折和融合，形成一个紧密的纽扣状结构，占据精子细胞核前端的凹陷处。本研究已产生细胞化学和组织学证据，以证明帚尾岩袋鼠精子顶体中肌动蛋白丝（F-肌动蛋白，由鬼笔环肽-异硫氰酸荧光素标记）的出现与附睾中顶体塑形过程在时间和空间上相关，这一过程通过在附睾成熟的所有阶段都存在于顶体中的单体肌动蛋白（G-肌动蛋白，由Rh-DNase I标记）池来实现。在睾丸精子的顶体中未检测到F-肌动蛋白，但在附睾头和附睾体精子的内折和浓缩顶体中发现了F-肌动蛋白。当精子在附睾尾完成顶体塑形时，F-肌动蛋白从顶体区域消失。F-肌动蛋白的出现与顶体塑形事件之间的强相关性表明，睾丸后顶体的塑形可能取决于精子在附睾中转运时顶体内F-肌动蛋白精确的组装和拆卸顺序。因此，肌动蛋白丝可能在顶体转化中发挥重要作用，因为它们通常参与体细胞的形态变化。
