CHARACTERIZATION OF 2 ATYPICAL PROMOTERS AND ALTERNATE MESSENGER-RNA PROCESSING IN THE MOUSE THY-1.2 GLYCOPROTEIN GENE
CHARACTERIZATION OF 2 ATYPICAL PROMOTERS AND ALTERNATE MESSENGER-RNA PROCESSING IN THE MOUSE THY-1.2 GLYCOPROTEIN GENE
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DOI：
10.1128/mcb.6.8.2923
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发表时间：
1986-08-01
影响因子：
5.3
通讯作者：
EVANS, GA
中科院分区：
文献类型：
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作者：
INGRAHAM, HA;EVANS, GA
通过DNA测序、引物延伸分析和缺失分析，对小鼠Thy-1.2糖蛋白基因的启动子和5'侧翼区域进行了表征。转录起始位点与编码Thy-1.2糖蛋白的基因上游的两个独立外显子相对应。我们证明小鼠Thy-1.2基因是从基因组序列中相隔260个碱基对的两个非典型启动子转录而来的。这些启动子既不包含TATAAG，也不包含GGPyCCAATCT同源序列，但在每个起始位点的-48处定义了一个保守的nonamer CTCCCTGCT。两个Thy-1.2 mRNA物种的1835和1939核苷酸在mRNA的5'非翻译区不同，因此通过mRNA剪接从单个Thy-1.2基因转录到相同的下游外显子上。从两个Thy-1.2启动子中的任何一个启动子表达细菌氯霉素乙酰转移酶基因的重组基因组表明，每个启动子都独立起作用，不直接在淋巴样细胞中进行细胞特异性表达。Thy-1.2基因-68上游的5”侧翼区域可以在不改变细胞类型特异性表达的情况下被消除。这表明负责组织和发育阶段特异性表达Thy-1.2基因的调控元件不存在于5'侧DNA中，而可能位于启动子的下游。
The promoter and 5'' flanking region of the mouse Thy-1.2 glycoprotein gene were characterized by DNA sequencing, primer extension analysis, and deletion analysis. Transcriptional initiation sites were identified which corresponded to two separate exons upstream of the portion of the gene encoding the Thy-1.2 glycoprotein. We demonstrated that the mouse Thy-1.2 gene was transcribed from two atypical promoters separated by 260 base pairs in the genomic sequence. These promoters contained neither TATAAG nor GGPyCCAATCT homologous sequences but defined a conserved nonamer CTCCCTGCT at -48 from each initiation site. Two Thy-1.2 mRNA species of 1835 and 1939 nucleotides, differing in the 5'' untranslated region of the mRNA, were thus transcribed from the single Thy-1.2 gene by mRNA splicing to the same downstream exon. Recombinant genomes in which the bacterial chloramphenicol acetyltransferase gene was expressed from either of the two Thy-1.2 promoters demonstrated that each promoter functioned independently and did not direct cell-specific expression in lymphoid cells. The 5'' flanking region of the Thy-1.2 gene upstream of -68 could be eliminated without altering cell-type-specific expression. This suggests that regulatory elements responsible for tissue and developmental stage-specific expression of the Thy-1.2 gene are not present in the 5'' flanking DNA but may reside downstream of the promoters.