ABNORMAL MANCHETTE DEVELOPMENT IN SPERMATIDS OF AZH/AZH MUTANT MICE
ABNORMAL MANCHETTE DEVELOPMENT IN SPERMATIDS OF AZH/AZH MUTANT MICE
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DOI：
10.1002/aja.1001880109
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发表时间：
1990-05-01
影响因子：
--
通讯作者：
RUSSELL, LD
中科院分区：
文献类型：
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作者：
MEISTRICH, ML;TROSTLEWEIGE, PK;RUSSELL, LD
本研究采用透射电子显微镜观察azh/azh突变小鼠精子发生过程中的伪足发育，目的是确定精子细胞发育的初始步骤中哪些是异常的。在纯合突变体中，精子发生在数量上是正常的，但100%的精子核产生了异常的形状。在步骤8-9中观察到的第一个缺陷是许多柄状微管的异常定位。除了位于顶体尾侧缘的正常顶体形成区域外，这些微管还被定向到通常与顶体形成不相关的质膜区域。在第10-12步，长柄微管片通常位于沿质膜的异位位置沿着，而不是也与核膜结合。肩袖的精细结构外观通常正常;缺陷似乎位于细胞内的该位置。在许多步骤8-10中，观察到精子细胞核内陷和外翻，总是与一些Manchette微管位置的不规则性相关;这些说明了Manchette微管使核形状变形的能力。核的不规则性在精子发生过程中一直存在。这些观察结果与以下假设一致：肩突至少参与精子核成形的某些方面，并且肩突形成的不适当定位是由azh位点的缺陷等位基因引起的原发性异常的可能候选者。
A study of manchette development during spermiogenesis in azh/azh mutant mice was carried out by thin-section transmission electron microscopy with the goal of determining which of the initial steps in spermatid development are aberrant. In the homozygous mutant, spermatogenesis was quantitatively normal; but 100% of the sperm nuclei produced had abnormal shapes. The first defect, observed in steps 8-9, was the abnormal positioning of many manchette microtubules. These microtubules were directed towards regions of the plasma membrane not normally associated with manchette formation, in addition to being located at the caudal rim of the acrosome in the normal region of manchette formation. At steps 10-12, sheets of manchette microtubules were often in ectopic positions along the plasma membrane, rather than in association with the nuclear membrane as well. The fine structural appearance of the manchette was generally normal; the defect appeared to be in this positioning within the cell. In many step 8-10 spermatids nuclear invaginations and evaginations were observed, always associated with irregularities in the position of some of the manchette microtubules; these illustrate the capacity of manchette microtubules to deform nuclear shape. The nuclear irregularities remained throughout spermiogenesis. These observations are consistent with the hypothesis that the manchette is involved in at least some aspects of sperm nuclear shaping and that the improper positioning of manchette formation is a likely candidate for the primary abnormality resulting from a defective allele at the azh locus.