Structure of the chromosomal chicken progesterone receptor gene.

We have isolated cosmid clones containing the chromosomal chicken progesterone receptor gene. The gene consists of eight exons and is approximately 38 kilobases long. Individual exons correlate well with conserved functional domains of the receptor molecule. Alternative polyadenylylation in the second intron results in a putative non-hormone-binding protein. The cap site of the gene is heterogeneous over at least 14 base pairs and lies in a very G + C-rich region. The promoter lacks "TATA" and "CAAT" boxes, but CCGCCC motifs exist in the surrounding region.