Spermatogenesis in the mouse 2. Amino acid incorporation into basic nucleoproteins of mouse spermatids and spermatozoa.
Spermatogenesis in the mouse 2. Amino acid incorporation into basic nucleoproteins of mouse spermatids and spermatozoa.
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小鼠精子发生 2. 氨基酸掺入小鼠精细胞和精子的碱性核蛋白中。
DOI：
10.1095/biolreprod25.5.1041
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发表时间：
1981
影响因子：
3.6
通讯作者：
Zirkin,BR
中科院分区：
文献类型：
--
作者：
MayerJr,JF;Chang,TS;Zirkin,BR
本研究的目的是确定小鼠精子细胞的蛋白质，睾丸内注射[3H]精氨酸和[3H]赖氨酸最初纳入，并确定这些蛋白质的命运在随后的精子细胞分化。在注射后2小时和7天之间的时间间隔，细长的精子细胞核被分离的睾丸凭借其抵抗超声波处理，和成熟的精子核被分离的附睾。从分离的精子细胞和精子核中提取碱性蛋白，并在酸性尿素聚丙烯酰胺凝胶上进行电泳。注射后2小时，[3H]精氨酸出现在一些精子细胞碱性蛋白中，包括“睾丸特异性”蛋白（TP）和鱼精蛋白。正如以前的研究所预期的那样，只有一类标记的蛋白质，鱼精蛋白，通过精子发生和精子成熟7天后完成保留。与此形成鲜明对比的是，[3H]赖氨酸最初仅掺入精子细胞TP蛋白中，仅保留3天，然后丢失。我们之前的放射自显影研究（Mayer和Zirkin，1979）表明，睾丸内注射的[3H]赖氨酸最初在染色质凝聚开始时（第12步和第13步后期）掺入伸长的精子细胞核中，保留3天直至染色质凝聚完成（第14步），然后丢失。目前的结果，再加上我们以前的放射自显影研究的结果，证明了惊人的时间之间的关系，第一次出现的新合成的TP蛋白和启动染色质凝聚在精子细胞核的后期步骤12，和TP蛋白的损失和完成染色质凝聚在精子细胞核的步骤14。
The present studies were designed to identify mouse spermatid proteins into which intratesticularly injected [3H] arginine and [3H] lysine were initially incorporated and to determine the fates of those proteins during subsequent spermatid differentiation. At intervals between 2 h and 7 days after injections, elongated spermatid nuclei were isolated from the testes by virtue of their resistance to sonication, and mature sperm nuclei were isolated from the epididymides. Basic proteins were extracted from isolated spermatid and sperm nuclei and subjected to electrophoresis on acid-urea polyacrylamide gels. Two hours after injection, [3H] arginine was seen in a number of spermatid basic proteins, including both the “testis-specific” protein (TP) and the protamines. As expected from previous studies, only one class of these labeled proteins, protamine, was retained through the completion of spermiogenesis and sperm maturation 7 days later. In striking contrast, [3H] lysine was initially incorporated only into the spermatid TP protein, was retained for only 3 days, and was then lost. Our previous autoradiographic study (Mayer and Zirkin, 1979) demonstrated that intratesticularly injected [3H] lysine was initially incorporated into elongating spermatid nuclei at the initiation of chromatin condensation (late step 12 and step 13), was retained for 3 days through the completion of chromatin condensation (step 14), and was then lost. The present results, taken together with the results of our previous autoradiographic study, demonstrate striking temporal relationships between the first appearance of newly synthesized TP protein and the initiation of chromatin condensation in spermatid nuclei of late step 12, and between the loss of TP protein and the completion of chromatin condensation in spermatid nuclei of step 14.