Cloning, structural organization, and transcriptional activity of the rat vitamin K-dependent gamma-glutamyl carboxylase gene.

The vitamin K-dependent gamma-glutamyl carboxylase gene was cloned from a rat liver genomic DNA library and the structural organization of this gene was determined. The carboxylase gene is 16.3 kb in length and contains 15 exons and 14 introns. DNA sequence analysis revealed that all 14 introns were U2-Type GT-AG introns. A 2.8-kb DNA fragment corresponding to the 5'-flanking region of the cloned gene demonstrated transcriptional activity in a rat liver cell line that is known to express the endogenous carboxylase gene. DNA sequence analysis of the proximal 331 bp of this 5'-flanking sequence reveals the absence of an identifiable TATA box. Consensus sequences for several transcription factors that may be important in regulating its tissue specific expression were identified. The isolation and characterization of the rat carboxylase gene provides essential information for the analysis of its regulation in vitro and in transgenic animal models.