Isolated polynucleotides comprising an OLIG1 mini-promoters are provided. The mini-promoter may be operably linked to an expressible sequence, e.g. reporter genes, genes encoding a polypeptide of interest, guide RNA, regulatory RNA sequences such as miRNA, siRNA, anti-sense RNA, etc., and the like. The promoter may also be provided in a vector, for example in combination with an expressible sequence. The polynucleotides find use in a method of expressing a sequence of interest, e.g. for identifying or labeling cells, monitoring or tracking the expression of cells, gene therapy, etc.