Regulation of expression of glial filament acidic protein.

The regulation of cell type-specific expression of the gene encoding glial filament acidic protein (GFAP) was examined by introducing various deletion mutants of the gene into GFAP-expressing (U251 human astrocytoma) and non-expressing (HeLa) cell lines, and measuring their transcriptional activity in an RNAase protection assay. The expression of GFAP is influenced by a number of cis-acting elements. A domain that resides between nucleotides -1631 and -1479 can confer cell type-specific expression when coupled to a heterologous gene. We also present evidence for the existence of a negative regulatory element that resides within the first intron of the GFAP gene.