一种5S基因转录因子与5S RNA的关联以及细胞分化过程中该因子水平的改变。

Association of a 5S gene transcription factor with 5S RNA and altered levels of the factor during cell differentiation.

作者信息

Honda B M, Roeder R G

出版信息

Cell. 1980 Nov;22(1 Pt 1):119-26. doi: 10.1016/0092-8674(80)90160-9.

Abstract

We have previously purified from Xenopus ovaries a protein factor (TF IIIA) which is necessary for the accurate in vitro transcription of 5S RNA genes. We now report that this factor (a 5S gene transcription effector) is identical by immunological, chemical and functional criteria to the protein associated with 5S RNA (the gene product) as a 7S ribonucleoprotein (RNP) complex in immature oocytes. After oocyte maturation, TF IIIA is no longer detectable functionally or immunologically in unfertilized eggs, which do not synthesize 5S RNA in vitro. Moreover, we cannot detect TF IIIA immunologically in extracts fron Xenopus somatic cells which, nevertheless, efficiently transcribe 5S genes.

摘要

我们之前从非洲爪蟾卵巢中纯化出一种蛋白质因子（TF IIIA），它是5S RNA基因在体外准确转录所必需的。我们现在报告，根据免疫学、化学和功能标准，这种因子（一种5S基因转录效应物）与未成熟卵母细胞中作为7S核糖核蛋白（RNP）复合体与5S RNA（基因产物）相关联的蛋白质是相同的。卵母细胞成熟后，在未受精的卵中，无论是在功能上还是免疫学上都无法检测到TF IIIA，这些未受精的卵在体外不合成5S RNA。此外，我们在非洲爪蟾体细胞的提取物中无法通过免疫学方法检测到TF IIIA，然而，这些体细胞却能高效转录5S基因。