DLX-7 homeobox gene regulates c-myc and GATA-1 gene expression in different stages respectively.

Homeobox genes code for transcription factors with a highly conserved DNA binding motif, but their target genes are largely unknown. We have shown that inhibition of the DLX-7 homeobox gene by an antisense oligonucleotide decreased the expression of c-myc and GATA-1 genes. Nuclear run-on assay revealed decreased transcriptional activity of c-myc but not of GATA-1 after DLX-7 antisense treatment. Actinomycin D chase experiments demonstrated that GATA-1 mRNA became unstable as a result of DLX-7 inhibition, whereas c-myc mRNA stability was unaffected. These results suggest that DLX-7 may regulate c-myc and GATA-1 genes at transcriptional and post-transcriptional levels.