Regulation of the Xenopus laevis transcription factor IIIA gene during oogenesis and early embryogenesis: negative elements repress the O-TFIIIA promoter in embryonic cells.
Regulation of the Xenopus laevis transcription factor IIIA gene during oogenesis and early embryogenesis: negative elements repress the O-TFIIIA promoter in embryonic cells.
复制标题
非洲爪蟾转录因子 IIIA 基因在卵子发生和早期胚胎发生过程中的调节：负元件抑制胚胎细胞中的 O-TFIIIA 启动子。
DOI：
10.1016/0012-1606(91)90123-k
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发表时间：
1991
影响因子：
2.7
通讯作者：
Taylor,WL
中科院分区：
文献类型：
--
作者：
Pfaff,SL;Hall,RK;Hart,GC;Taylor,WL
Expression of theXenopus laevistranscription factor IIIA (TFIIIA) gene is developmentally regulated. In this study we have used defined nucleotide mutations to mapcis-elements involved in transcriptional regulation of the promoter for oocyte-TFIIIA (O-TFIIIA) in stage II–IV oocytes, stage VI oocytes, and tail bud embryos. During oogenesis O-TFIIIA mRNA levels decline 5- to 10-fold, and during early embryogenesis O-TFIIIA mRNA levels decline approximately 106-fold per cell. In stage II–IV oocytes we find evidence for at least three distinct positive-actingcis-elements that contribute to the efficient expression of O-TFIIIA. These elements are located between −1800 to −425, −280 to −235, and −235 to −220. The most distalcis-element(s) appears to be developmentally regulated during oogenesis, since deletion of nucleotide sequences from −1800 to −425 does not reduce O-TFIIIA expression in stage VI oocytes. However, the twocis-elements located between −280 to −235 and −235 to −220 are required for the efficient expression of O-TFIIIA in stage VI oocytes. In tail bud embryos we find evidence for several developmentally regulated positive and negativecis-elements involved in O-TFIIIA expression. The positive-actingcis-elements are located between −159 to −110 and −110 to −58. The negative-actingcis-elements are found at positions −425 to −350 and −200 to −159. In addition to the developmentally regulated elements controlling O-TFIIIA gene expression in tail bud embryos, the positive-actingcis-elements active during oogenesis (located between −280 to −235 and −235 to −220) are also active during early embryogenesis. Thus, transcription from the O-TFIIIA promoter appears to be regulated by a combination of constitutive positive factors and developmentally regulated positive and negative factors during oogenesis and early embryogenesis.
