The transgene comprises a 2.2 kb 5' flanking fragment containing the promoter and upstream regulatory elements of the human glial fibrillary acidic protein gene joined to a 912 bp DNA fragment encoding human CDK4 followed by a 0.5 kb fragment containing an intron and the polyadenylation signal from the mouse protamine 1 gene. RT-PCR demonstrated expression of mRNA and western blot analysis of protein in astrocytes. (J:86020)