| First Author | Grillot DA | Year | 1997 |
| Journal | J Immunol | Volume | 158 |
| Issue | 10 | Pages | 4750-7 |
| PubMed ID | 9144489 | Mgi Jnum | J:40206 |
| Mgi Id | MGI:87548 | Doi | 10.4049/jimmunol.158.10.4750 |
| Citation | Grillot DA, et al. (1997) Genomic organization, promoter region analysis, and chromosome localization of the mouse bcl-x gene. J Immunol 158(10):4750-7 |
| abstractText | The bcl-x gene, a bcl-2 family member, is highly regulated during lymphoid development, and its expression modulates apoptosis in lymphoid and other cell populations. Several forms of bcl-x mRNAs with different biologic functions have been described in rodents and humans. In this study, we have determined the organization and promoter region of the mouse bcl-x gene in an effort to understand the molecular basis for the different bcl-x mRNA species identified in tissues. We show that mouse bcl-x maps to the distal mouse chromosome 2 at approximately 89 cM, and exhibits a three-exon structure with an untranslated first exon and a facultative first intron. The coding region of bcl-x, is generated by the juncture of exons II and III through a splicing reaction, whereas bcl-x(s) is generated by an alternatively utilized donor splice site located within exon II. Analysis of multiple cDNAs and primer extension experiments revealed major transcription initiation sites in brain and thymus within a GC-rich region, with multiple Sp1-binding motifs located upstream of exon I. Another promoter was mapped to a 57-bp region localized upstream of the translation initiation codon by transfection of reporter constructs into FL5.12 and K562 cell lines. The remarkable similarity between the genomic regions of bcl-2 and bcl-x suggests that these genes have evolved from a common ancestral gene or through gene duplication. |
