Gene expression during mammalian spermatogenesis. I. Evidence for stage-specific synthesis of polypeptides in vivo.
Gene expression during mammalian spermatogenesis. I. Evidence for stage-specific synthesis of polypeptides in vivo.
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哺乳动物精子发生过程中的基因表达。
DOI：
10.1095/biolreprod28.2.483
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发表时间：
1983
影响因子：
3.6
通讯作者：
Hecht,NB
中科院分区：
文献类型：
--
作者：
Stern,L;Gold,B;Hecht,NB
在睾丸内注射[35S]蛋氨酸或[3H]亮氨酸后，通过单位重力沉降和Percoll平衡密度梯度离心，从小鼠睾丸细胞悬浮液中纯化出四种睾丸细胞类型（粗线精细胞、圆形精细胞、细长精细胞和残体）。对睾丸细胞中蛋白质中放射性标记氨基酸含量的测量显示，在一定数量的细胞中，粗线精母细胞的同位素含量是圆形精母细胞的5.4倍，而圆形精母细胞的同位素含量是细长精母细胞的2.4倍。通过二维凝胶电泳对四种睾丸细胞体内合成的多肽进行分析，发现精子发生过程中蛋白质合成发生了定性和定量的变化。在电泳方法提供的检测水平上，粗线精细胞和圆形精细胞合成的多肽数量大致相当，而细长精细胞和残体合成的多肽数量则减少。在精子发生过程中检测到分子量从16,500到82,000的多肽的定量变化。对于所检查的每种细胞类型，至少有5%的多肽是独特的或非常丰富的。这些研究表明，相当数量的多肽的表达是特定于精子发生的某些阶段。
Following intratesticular injection of [35S]methionine or [3H]leucine, four testicular cell types (pachytene spermatocytes, round spermatids, elongating spermatids and residual bodies) were purified from mouse testicular cell suspensions by unit gravity sedimentation and equilibrium density gradient centrifugation through Percoll. Measurement of the amount of radiolabeled amino acid incorporated into protein in the testicular cells revealed that for a constant number of cells, pachytene spermatocytes incorporated 5.4 times more isotope than round spermatids, which incorporated 2.4 times more isotope than elongating spermatids. Analysis by two-dimensional gel electrophoresis of the polypeptides synthesized in vivo in the four testicular cell types demonstrated qualitative and quantitative changes in protein synthesis during spermatogenesis. At the level of detection provided by the electrophoretic methods used, pachytene spermatocytes and round spermatids synthesized approximately equivalent numbers of polypeptides while the number of polypeptides synthesized in elongating spermatids and residual bodies was decreased. Quantitative changes for polypeptides ranging in molecular weight from 16,500 to 82,000 were detected during spermatogenesis. For each cell type examined, aminimumof 5% of the polypeptides appear to be either unique or greatly enriched. These studies indicate that the expression of a sizable number of polypeptides is specific to certain stages of spermatogenesis.