Characterization of Key Regulatory Elements of LCRG1 Promoter / 生物化学与生物物理进展

ABSTRACT

LCRG1(laryngeal carcinoma related gene1,LCRG1),a new candidate tumor suppressor gene of laryngeal carcinoma.However,it is known little about the possible regulatory mechanisms of LCRG1 gene expression.Restriction endonuclease digestion was used to obtain a set of the 5',or 3'deletion mutants from the region(-169～+127) of the LCRG1 gene.It has been found that the minimal promoter of the LCRG1 gene is mapped at the region from-169～-57.Linker scanning mutational analysis in the region(-169～+127) of the LCRG1 gene was used to identify the crucial cis-elements within the promoter region,The key cis-elements are within the region from-137～-122.SP1,E2F1/DP1,EKLF and ZF9 transcription factor binding site sites were predicted in the region by bioinformatics analysis.Co-transfection with each of a panel of the expression plasmids of the known transcription factors with the relevant reporter construct indicates Sp1 is potent transcription factor for enhancement of the promoter activity,SP1 can also up-regulate the endogenous expression of LCRG1 gene.Electrophoretic mobility shift assay(EMSA) was applied to verify that the key cis-elements of LCRG1 gene exist sequence of Sp1 binding sites.The findings,which showed that the key cis-elements within the region from 137～-122 play an important role in expression of the LCRG1 gene,provide a novel evidence for further study of the function of LCRG1 gene.