Fig. 2.

Gene structure and proximal promoter sequence for human ASNS. A: exon-intron structure and size of the human ASNS gene. The translation start site is within exon 3 and the stop site within exon 13, so tan exon boxes represent 3′- and 5′-untranslated regions of the mRNA, and protein coding exons are shown in green. B: sequence of the proximal 173 bp for the human ASNS promoter. Designated are a number of transcription factor binding sites that have been identified by in vivo footprinting and single nucleotide mutagenesis to contribute to either basal or stress-induced transcription (15, 57, 101). Details of the role for each of these sequences are discussed in the text.