Genomic organization, alternative splicing and tissues expression of porcine CREB3L4 gene.

CREB3L4 (cAMP response element binding protein3 like 4) belongs to mammalian CREB/ATF subfamily transcription factors featuring a unique putative transmembrane domain lined to the bZIP region in their C-terminals. We report here the cloning of porcine CREB3L4 and its alternative splicing variant. The open reading frame of normal CREB3L4 covers 1,188 bp and encodes a 395-amino acid polypeptide, whereas its variant encodes a C-terminal truncated protein comprising only 271 amino acids. The genomic sequence of porcine CREB3L4 spans approximately 6 kb consisted of ten exons and nine introns, and maps closely to Jumping translocation breakpoint gene in a head-to-head manner on the q arm of Sus Scrofa chromosome 4. Tissue expression analysis by RT-PCR indicates that normal porcine CREB3L4 is ubiquitously expressed with relatively high abundance in stomach, liver, cerebellum, and is a predominant form in various tissues, whereas the splicing variant is expressed at extremely low level in all examined tissues. Our study will lay the groundwork for the further investigation on the physiological function of CREB3L4 in pig models.