Contrasting levels of transferrin gene activity in cultured rat Sertoli cells and intact seminiferous tubules.
Contrasting levels of transferrin gene activity in cultured rat Sertoli cells and intact seminiferous tubules.
复制标题
培养的大鼠支持细胞和完整生精小管中转铁蛋白基因活性的对比水平。
DOI：
10.1073/pnas.83.21.8177
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发表时间：
1986
影响因子：
11.1
通讯作者：
Kierszenbaum,AL
中科院分区：
文献类型：
--
作者：
Lee,NT;Chae,CB;Kierszenbaum,AL
本文应用蛋白质双向聚丙烯酰胺凝胶电泳和RNA转移印迹杂交技术，研究了大鼠转铁蛋白基因在性未成熟和性成熟大鼠睾丸支持细胞、睾丸和离体曲细精管中的活性和表达。虽然运铁蛋白基因在培养的支持细胞中积极参与mRNA的转录和mRNA被翻译成分泌产物，很少的运铁蛋白mRNA和运铁蛋白存在于整个睾丸和分离的曲细精管。培养后的支持细胞显示出时间依赖性的转铁蛋白基因活化，并且在接种后6小时可以检测到丰富的转铁蛋白mRNA。一个类似的研究，使用完整的曲细精管段从相同的大鼠未能显示出可比的时间激活转铁蛋白基因。这项研究的结果，加上以前的实验数据，表明支持细胞在体内最有可能不积极参与睾丸转铁蛋白的合成，而是主要依赖于由肝脏提供的血浆转铁蛋白。在体外，从体内操作的生理限制释放的支持细胞迅速激活转铁蛋白基因，导致大量新合成的支持细胞转铁蛋白产物。
Two-dimensional polyacrylamide gel electrophoresis of proteins and transfer blot hybridization of RNA have been used to study the activity and expression of the rat transferrin gene in cultured Sertoli cells and in whole testis and isolated seminiferous tubules of sexually immature and mature rats. Although the transferrin gene in cultured Sertoli cells is actively engaged in the transcription of mRNA and the mRNA is translated into a secretory product, little transferrin mRNA and transferrin protein are present in whole testes and isolated seminiferous tubules. Sertoli cells upon culturing show a time-dependent transferrin gene activation, and abundant transferrin mRNA can be detected 6 hr after plating. A similar study using intact seminiferous tubular segments from the same rats failed to show a comparable temporal activation of the transferrin gene. Results of this study, together with previous experimental data, suggest that Sertoli cells in vivo are most likely not actively engaged in the synthesis of a testicular transferrin but, instead, rely mainly on plasma transferrin contributed by the liver. In vitro, Sertoli cells, released from the physiological constraints that operate in vivo, rapidly activate the transferrin gene, resulting in abundant newly synthesized Sertoli cell transferrin product.