Ratner L, Thielan B, Collins T
Nucleic Acids Res. 1987 Aug 11;15(15):6017-36. doi: 10.1093/nar/15.15.6017.
The c-sis gene encodes the B polypeptide chain of platelet-derived growth factor (PDGF), and is expressed in a number of normal and pathological conditions. In order to study the control of synthesis of the human c-sis product, we have initiated a study of two regions of this genetic locus which regulate transcription and translation. A clone of the 5' portion of the gene was obtained which included 1361 nucleotides upstream of the RNA initiation site. Transcriptional promoter activity of this region was demonstrated in normal and transformed cells using a plasmid with the sequences upstream of the c-sis RNA initiation site fused to an indicator gene, chloramphenicol acetyl transferase. Experiments were also performed to identify other possible regulatory regions of the c-sis gene. These data demonstrated that a portion of the c-sis first exon encoding the 5' untranslated region of the c-sis mRNA inhibited synthesis of the PDGF B product in vitro. These results define regions of the c-sis gene whose activity may be important in the regulation of transcription and translation under normal conditions and in the pathogenesis several human diseases.
c-sis基因编码血小板衍生生长因子（PDGF）的B多肽链，在多种正常和病理条件下均有表达。为了研究人类c-sis产物合成的调控机制，我们启动了对该基因位点两个调控转录和翻译区域的研究。获得了该基因5'部分的一个克隆，其包含RNA起始位点上游1361个核苷酸。使用一个质粒，将c-sis RNA起始位点上游的序列与指示基因氯霉素乙酰转移酶融合，在正常细胞和转化细胞中证明了该区域的转录启动子活性。还进行了实验以鉴定c-sis基因的其他可能调控区域。这些数据表明，c-sis第一个外显子中编码c-sis mRNA 5'非翻译区的一部分在体外抑制了PDGF B产物的合成。这些结果确定了c-sis基因的区域，其活性在正常条件下以及几种人类疾病的发病机制中对转录和翻译的调控可能很重要。
