Chicken oviduct progesterone receptor: location of specific regions of high-affinity binding in cloned DNA fragments of hormone-responsive genes.

We have used a DNA-cellulose competitive binding assay to measure the extent of displacement of the chicken oviduct progesterone-receptor complex from calf thymus DNA-cellulose by purified cloned fragments of genomic DNA. Several DNA fragments from hormonally responsive genes coding for egg-white proteins were found to be efficient competitors for either crude or partially purified receptor complexes when compared with calf thymus DNA. Data obtained with deletion mutations constructed in vitro allowed delineation of a specific region necessary for strong competition, located 250--300 bp upstream from the mRNA startsite of the ovalbumin gene. Sequence homologies with this 5'-upstream region were observed in other fragments of the ovalbumin, conalbumin, ovomucoid, X and Y genes, which were also efficient competitors. Based on a comparison of such sequences of homology, a consensus sequence that may constitute a region binding progesterone-receptor complex has been constructed: ATCCCTTATTATTCTGGTTTGTA. The results suggest that specific double-stranded DNA sequences are recognized by the oviduct progesterone-receptor complex in vitro, and are relevant to the question of whether specific DNA sequences are directly involved as genomic binding sites for steroid receptors.