MEMBRANE SPECIALIZATIONS ASSOCIATED WITH THE ACROSOMAL COMPLEX OF SEA-URCHIN SPERM AS REVEALED BY IMMUNOCYTOCHEMISTRY AND FREEZE-FRACTURE REPLICATION
MEMBRANE SPECIALIZATIONS ASSOCIATED WITH THE ACROSOMAL COMPLEX OF SEA-URCHIN SPERM AS REVEALED BY IMMUNOCYTOCHEMISTRY AND FREEZE-FRACTURE REPLICATION
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DOI：
10.1002/mrd.1120230408
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发表时间：
1989-08-01
期刊：
影响因子：
--
通讯作者：
COOK, S
中科院分区：
文献类型：
--
作者：
LONGO, FJ;GEORGIOU, C;COOK, S
采用冷冻断裂复制和电子显微镜免疫化学进行了观察，以确定由210 kDa蛋白占据的质膜结构域的结构相关性，该蛋白参与海胆精子的顶体反应并被单克隆抗体J10/14识别（Trimmer等人：Cell 40：697-703，1985; Proceedings of the National Academy of Sciences of the United States of America 83：9055-9059，1986）。顶体完整的精子的免疫金-J10/14染色是强烈的单独的鞭毛和一个狭窄的衣领刚刚后方的精子顶体复合体周围（顶体囊泡和subjacial前核窝含有g-肌动蛋白）。金颗粒的计数揭示了沿着与顶体复合体相关的质膜的密度（颗粒平均数/μ m2表面积）比限定精子头部其余部分的膜大沿着。J10/14染色的衣领是同构的，在质膜的P-面和薄的细胞质区域，围绕顶体复合体的膜内颗粒的密集聚集。在顶体反应的精子，强烈的J10/14染色是不明显的，在所有标本。在与A-23187反应的精子顶体中，与前顶体复合体、核和精子膜界定组分相关的金颗粒密度以及沿整个精子表面沿着的颗粒总平均数增加。伴随着这种染色变化的是膜内颗粒和细胞质的项圈的消失/减少。这些观察结果表明，质膜成分（210 kDa的蛋白质和膜内颗粒）和细胞质的衣领，这是与顶体复合体的功能，以及结构相关。颗粒密度分布沿着顶体反应和非顶体反应的精子的分析表明，观察到的不同染色模式可能是由于在顶体反应时识别隐蔽位点而引起的。
Observations, employing freeze fracture replication and electron microscopic immunochemistry, have been carried out to determine structural correlations of the plasma membrane domain occupied by a 210 kDa protein involved in the acrosomal reaction of sea urchin sperm and recognized by the monoclonal antibody, J10/14 (Trimmer et al.: Cell 40:697-703, 1985; Proceedings of the National Academy of Sciences of the United States of America 83: 9055-9059, 1986). Immunogold-J10/14 staining of acrosome-intact sperm was intense alone the flagellum and a narrow collar just posterior to the sperm apex that surrounded the acrosomal complex (acrosomal vesicle and subjacent anterior nuclear fossa containing g-actin). Counts of gold particles revealed a density (average number of particles/.mu.m2 of surface area) eightfold greater along the plasma membrane associated with the acrosomal complex than membrane delimiting the remainder of the sperm head. The collar of J10/14 staining was isomorphic with a dense aggregation of intramembranous particles in the P-face of the plasma membrane and a thin cytoplasmic region that surrounded the acrosomal complex. In acrosome-reacted sperm, intense J10/14 staining was not apparent in all specimens. The density of gold particles associated with plasma membrane delimiting components of the former acrosomal complex, nucleus and mitochondrion, as well as the total average number of particles along the entire sperm surface, were increased in sperm acrosome-reacted with A-23187. Concomitant with this change in staining was the diappearance/reduction of the collars of intramembranous particles and cytoplasm. These observations indicate that plasma membrane components (210 kDa protein and intramembranous particles) and the collar of cytoplasm which are associated with the acrosomal complex are functionally, as well as structurally related. Analyses of particle density distributions along acrosome- and non-acrosome-reacted sperm suggest that the different staining patterns observed may be brought about by the recognition of cryptic sites at the time of the acrosomal reaction.