Identification of a negative regulatory element that inhibits c-mos transcription in somatic cells.
Identification of a negative regulatory element that inhibits c-mos transcription in somatic cells.
复制标题
鉴定抑制体细胞中 c-mos 转录的负调控元件。
DOI：
10.1128/mcb.12.5.2029-2036.1992
复制
发表时间：
1992
影响因子：
5.3
通讯作者：
Cooper,GM
中科院分区：
文献类型：
--
作者：
Zinkel,SS;Pal,SK;Szeberényi,J;Cooper,GM
我们使用瞬时表达试验来鉴定小鼠c- mos5 '侧序列中的酸作用区，当删除时，允许在NIH 3T3细胞中从c-mospromoter表达。这个负调控序列位于c-mosATG上游400到500个核苷酸，也抑制来自异源启动子的表达。除NIH 3T3细胞外，c-mosnegative调控序列在BALB/3T3细胞、PC12大鼠嗜铬细胞瘤细胞和A549人肺癌细胞中均有活性。位点特异性诱变确定了三个可能参与负调控活性的相互作用区域，位于ATG的-460，-425和-405附近。RNase保护分析表明，一旦负调控序列被删除，NIH 3T3细胞中的转录从通常在精母细胞中使用的相同转录起始位点开始，大约在ATG上游280个核苷酸处。然而，精母细胞启动子以外的缺失允许从逐渐下游的c-mossequence开始转录。卵母细胞启动子-53周围序列的缺失或突变对NIH 3T3细胞中c-mosconstruct的表达也没有什么影响。因此，NIH 3T3细胞中c-mos表达的主要决定因素是去除负调控序列，而不是利用独特的启动子。因此，c-mos负调控序列似乎通过抑制体细胞转录在组织特异性c-mos表达中发挥重要作用。
We have used transient expression assays to identify acis-acting region in the 5' flanking sequence of murine c-moswhich, when deleted, allows expression from the c-mospromoter in NIH 3T3 cells. This negative regulatory sequence, located 400 to 500 nucleotides upstream of the c-mosATG, also inhibited expression from a heterologous promoter. In addition to NIH 3T3 cells, the c-mosnegative regulatory sequence was active in BALB/3T3 cells, PC12 rat pheochromocytoma cells, and A549 human lung carcinoma cells. Site-specific mutagenesis identified three possibly interacting regions that were involved in negative regulatory activity, located around -460, -425, and -405 with respect to the ATG. RNase protection analysis indicated that once the negative regulatory sequences were deleted, transcription in NIH 3T3 cells initiated from the same transcription initiation sites normally utilized in spermatocytes, approximately 280 nucleotides upstream of the ATG. Deletions beyond the spermatocyte promoter, however, allowed transcription initiation from progressively downstream c-mossequences. Deletion or mutation of sequences surrounding the oocyte promoter at -53 also had little effect on expression ofc-mosconstructs in NIH 3T3 cells. Therefore, the major determinant ofc-mosexpression in NIH 3T3 cells was removal of the negative regulatory sequence rather than the utilization of a unique promoter. The c-mosnegative regulatory sequences thus appear to play a significant role in tissue-specific c-mosexpression by inhibiting transcription in somatic cells.