Comparison of promoter regions of SOX3, SOX14 and SOX18 orthologs in mammals.

SOX proteins constitute a large family of diverse and well conserved transcription factors implicated in the control of various developmental processes. Previously we have cloned and characterized human SOX3, SOX14 and SOX18 genes and performed functional characterization of their promoter regions. To better understand organization and function of SOX3, SOX14 and SOX18 promoters and to determine evolutionary conserved regulatory regions, we performed comparative genomic analyses of orthologous genes promoters. Mammalian orthologs of the human SOX3, SOX14 and SOX18 genes show high sequence identity in their promoter regions, particularly within basal promoters of the respective human genes. Binding sites for transcription factors NF-Y, Sp1 and USF1, previously shown to play critical roles in transcriptional regulation of these human genes, are highly conserved in sequence and position among diverse mammalian species. Conservation of binding sites might indicate their highly significant roles in maintaining the transcriptional regulation of these genes among different species.