Isolation and structural analysis of embryonic chicken pepsinogen gene: avian homologue of prochymosin gene.

Embryonic chicken pepsinogen gene was isolated from a chicken genomic library. This gene occupied approximately 3.5 kb of the genomic DNA and was separated into nine exons by eight introns. The positions of exon-intron junctions coincided with those in the human pepsinogen A gene and the bovine prochymosin gene. Southern blot analysis of chicken genomic DNA revealed that the structure of the isolated gene reflects the original structure in the chicken chromosome. At the same time, the presence of another copy of embryonic pepsinogen gene was suggested. 5'-flanking region of the isolated ECPg gene was analyzed.