Positive- and negative-acting promoter sequences regulate cell type-specific expression of the rat synapsin I gene
Biochemistry & Molecular Pharmacology
Graduate School of Biomedical Sciences; Department of Neurology
Life Sciences | Medicine and Health Sciences
The phosphoprotein synapsin I is expressed exclusively in neuronal cells. We are interested in elucidating the promoter sequences involved in cell type-specific expression of the synapsin I gene. The PC12 cell line expresses the 3.4 kb and 4.5 kb synapsin I mRNAs and is used to analyze cell type-specific gene expression. A series of deletion fragments of the rat synapsin I gene promoter were fused to the promoterless reporter gene encoding bacterial chloramphenicol acetyltransferase (CAT) for transfection analysis in PC12 cells and in HeLa cells, which do not express the gene. A -349 bp to +110 bp rat synapsin I promoter fragment contains a positive regulator, shown to be 33-times more active in PC12 cells than HeLa cells. Transfection of reporter plasmids containing up to 4.4 kb of rat synapsin I gene promoter sequences exhibit significantly reduced CAT activity in PC12 cells. The reduction in CAT expression was attributed to a negative regulator located between -349 bp and -1341 bp in the rat synapsin I promoter. Our results suggest that both positive and negative-acting sequence elements regulate cell type-specific expression of the rat synapsin I gene.
Brain Res Mol Brain Res. 1991 Oct;11(3-4):345-53.
Brain research. Molecular brain research
Howland, David S.; Hemmendinger, Liza M.; Carroll, Patrick D.; Estes, Patricia S.; Melloni, Richard H.; and DeGennaro, Louis J., "Positive- and negative-acting promoter sequences regulate cell type-specific expression of the rat synapsin I gene" (1991). GSBS Student Publications. 550.