Identification of a candidate alternative promoter region of the human Bcl2L11 (Bim) gene

BACKGROUND: Despite the importance of the BCL2L11 (BIM) protein in various apoptotic processes in development and disease, little is known of the promoter structure of the human BCL2L11 locus and of the cis-acting elements regulating expression of the human gene. RESULTS: In the search for novel promoter sequences in the human BCL2L11 locus, we have identified previously unrecognized genomic sequences displaying promoter activity and E2F responsiveness, and driving the expression of BCL2L11 coding transcripts. In man, transcripts originating from this novel putative promoter contribute significantly to total BCL2L11 mRNA expression in testis, heart and liver. In HEK293 cells, this novel candidate promoter originates BCL2L11 transcripts whose expression can be modulated by a known modulator of BCL2L11 expression (Trichostatin A) and by E2F, a characterized transcriptional regulator of BCL2L11 expression. CONCLUSION: The identification of a novel putative human BCL2L11 promoter provides new insights into the structure and regulation of the BCL2L11 locus.