Morphological and biochemical changes in the hepatic endoplasmic reticulum and Golgi apparatus of male Xenopus laevis after induction of egg-yolk protein synthesis by oestradiol-17β
Morphological and biochemical changes in the hepatic endoplasmic reticulum and Golgi apparatus of male Xenopus laevis after induction of egg-yolk protein synthesis by oestradiol-17β
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雌二醇-17β诱导卵黄蛋白合成后雄性非洲爪蟾肝内质网和高尔基体的形态和生化变化
DOI：
10.1016/0303-7207(76)90048-4
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发表时间：
1976
影响因子：
4.1
通讯作者：
J. Tata
中科院分区：
文献类型：
--
作者：
John A. Lewis;M. Clemens;J. Tata
本报告描述了雌激素诱导的雄性Xenopusliver中卵黄蛋白前体卵黄蛋白原合成的形态和生化变化。注射17-雌二醇β后3~9天，粗面光滑的内质网和高尔基体广泛增殖。亚细胞分级结果表明，激素处理后，微粒体的蛋白质和RNA含量增加，而内质网标志酶葡萄糖-6-磷酸酶的含量降低。除了可用于蛋白质合成的核糖体数量增加外，激素处理还提高了微粒体和核糖体制剂中每单位RNA的体外蛋白质合成能力。由核糖体制剂在体外合成的多肽显示，激素处理后丝氨酸含量增加，针对卵黄蛋白原的抗体可以免疫沉淀更多的核糖体。我们的数据与卵黄原蛋白是在粗面内质网的核糖体上合成，并在光滑内质网和高尔基体中进行加工和包装以供分泌的说法是一致的。卵黄蛋白原对激素诱导的反应包括早期阶段的膜增殖，以增加细胞合成、加工和分泌大量卵黄蛋白前体的能力。
This report describes morphological and biochemical changes accompanying oestrogen-induced synthesis of the egg-yolk protein precursor, vitellogenin, in maleXenopusliver. Extensive proliferation of the rough and smooth endoplasmic reticulum and the Golgi apparatus occurs between 3 and 9 days after administration of oestradiol-17β. Subcellular fractionation showed that microsomal fractions have an increased protein and RNA content after hormone treatment, whereas the level of the endoplasmic reticulum marker enzyme, glucose-6-phos-phatase, decreased. In addition to an increased number of ribosomes available for protein synthesis, hormone treatment enhances the in vitro protein synthetic capacity per unit of RNA, both in microsome and ribosome preparations. Polypeptides synthesized in vitro by ribosome preparations show an enrichment in serine content after hormone treatment and an increased proportion of ribosomes can be immunoprecipitated by antibodies directed against vitellogenin. Our data are consistent with the proposal that vitellogenin is synthesized on the ribosomes of the rough endoplasmic reticulum and processed and packaged for secretion in the smooth endoplasmic reticulum and Golgi apparatus. Response to hormonal induction of vitellogenin involves an early phase in which membrane proliferation occurs in order to increase the cellular capacity to synthesize, process and secrete large quantities of egg-yolk protein precursor.