c-mos expression in mouse oocytes is controlled by initiator-related sequences immediately downstream of the transcription initiation site.
c-mos expression in mouse oocytes is controlled by initiator-related sequences immediately downstream of the transcription initiation site.
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小鼠卵母细胞中的 c-mos 表达由紧邻转录起始位点下游的起始子相关序列控制。
DOI：
10.1128/mcb.11.10.5190-5196.1991
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发表时间：
1991
影响因子：
5.3
通讯作者：
Cooper,GM
中科院分区：
文献类型：
--
作者：
Pal,SK;Zinkel,SS;Kiessling,AA;Cooper,GM
我们采用瞬时表达分析来分析小鼠卵母细胞中指导 c-most 转录的序列。含有氯霉素乙酰转移酶 (CAT) 基因的质粒与 c-mos 5' 侧翼区域的 2.4 kb 或 731 bp 片段融合，当注射到生长中的卵母细胞核中时，可产生相似水平的 CAT 活性。 BAL 31 删除表明，可以去除主要转录起始位点上游最多 20 bp 的序列，而不会显着损失 CAT 活性。仅当这些缺失靠近转录起始位点时，启动子活性才会降低，转录起始位点位于 c-mosopen 阅读框中第一个 ATG 上游 53 个核苷酸处。另一方面，删除转录起始位点下游 20 个核苷酸内的序列会导致 CAT 表达量减少 10 倍。由于这些 5' 非翻译序列中的点突变，观察到启动子活性的类似降低。因此，紧邻转录起始位点下游的序列，包括存在于几个基因的起始元件中的共有序列（PyPyCAPyPyPyPyPy），似乎调节小鼠卵母细胞中的c-mos表达。对注射卵母细胞 RNA 的逆转录聚合酶链反应分析表明，这种调节在转录水平上很明显。因此，c-mosin 小鼠卵母细胞的表达似乎是由一个简单的启动子引导的，该启动子仅由紧邻转录起始位点周围的序列组成，包括非翻译前导序列中的起始元件。
We have employed transient expression assays to analyze the sequences that direct c-mostranscription in mouse oocytes. Plasmids containing the chloramphenicol acetyltransferase (CAT) gene fused to either a 2.4-kb or a 731-bp fragment from the 5′-flanking region of c-mosproduced similar levels of CAT activity when injected into nuclei of growing oocytes. BAL 31 deletions revealed that sequences up to 20 bp upstream of the major transcription start site could be removed without any significant loss of CAT activity. Promoter activity only decreased when these deletions closely approached the transcription start site, which was mapped at 53 nucleotides upstream of the first ATG in the c-mosopen reading frame. On the other hand, deletion of sequences within 20 nucleotides downstream of the transcription initiation site resulted in a 10-fold reduction in CAT expression. A similar decrease in promoter activity was observed as a result of point mutations in these 5′ untranslated sequences. Thus, sequences immediately downstream of the transcription start site, including a consensus sequence (PyPyCAPyPyPyPyPy) present in the initiator elements of several genes, appear to regulate c-mosexpression in mouse oocytes. Reverse transcription-polymerase chain reaction analysis of RNA from injected oocytes showed that this regulation is manifest at the transcriptional level. Expression of c-mosin mouse oocytes thus appears to be directed by a simple promoter consisting only of sequences immediately surrounding the transcription start site, including an initiator element in the untranslated leader.