Liu Tiffany Yi-Chen, Chen Huang-Hui, Lee Kun-Hsiung, Choo Kong-Bung
Department of Medical Research and Education, Taipei Veterans General Hospital, Shih Pai, Taipei, Taiwan.
Mol Reprod Dev. 2003 Jan;64(1):52-60. doi: 10.1002/mrd.10218.
We have previously reported a Krupple-like finger protein gene, Zfp352, which is expressed temporarily in two- to eight-cell mouse embryos. The Zfp352 gene is intron-less in the coding region but carries a solitary 4.3-kb intron in the 5'-untranslated region. In this study, we have analyzed the Zfp352 promoter activity in early embryos and in somatic cells. We determined that the major Zfp352 promoter, designated P1 and located upstream of exon 1, is utilized in both early embryos and in somatic cells. A TATA-like box and a transcription initiator element are discernible in the P1 promoter. We uncovered an alternative promoter, designated P2, in the intron. 5'-Rapid amplification of cDNA ends and real-time RT-PCR experiments indicated that the P2 promoter is weak and is probably fortuitous in early embryos. In somatic cells, however, transfection experiments showed that P2 is as active as P1 as a promoter. Furthermore, P2 appears to be composed of two different subdomains used differentially for transcription initiation in embryos and in somatic cells. Our observations may bear relevance in explaining developmental deficiencies associated with somatic cell cloning experiments.
我们之前报道过一种类 Krupple 结构域蛋白基因 Zfp352，它在二细胞至八细胞期的小鼠胚胎中短暂表达。Zfp352 基因的编码区无内含子，但在 5'非翻译区有一个单独的 4.3 kb 内含子。在本研究中，我们分析了 Zfp352 在早期胚胎和体细胞中的启动子活性。我们确定主要的 Zfp352 启动子（命名为 P1，位于外显子 1 上游）在早期胚胎和体细胞中均被使用。在 P1 启动子中可识别出一个类 TATA 框和一个转录起始元件。我们在内含子中发现了另一个启动子，命名为 P2。5'-cDNA 末端快速扩增和实时 RT-PCR 实验表明，P2 启动子较弱，在早期胚胎中可能是偶然出现的。然而，在体细胞中，转染实验表明 P2 作为启动子与 P1 一样活跃。此外，P2 似乎由两个不同的亚结构域组成，在胚胎和体细胞中用于转录起始的方式不同。我们的观察结果可能与解释体细胞克隆实验相关的发育缺陷有关。
