Nuclear proteins from Drosophila melanogaster embryos which specifically bind to simple homopolymeric sequences poly [(dT-dG).(dC-dA)].

The binding of nuclear proteins from Drosophila melanogaster embryos to simple homopolymeric DNA sequences was studied. Nuclear proteins were electrophoresed, transferred onto nitrocellulose and incubated with labelled synthetic homopolymers or natural fragment containing simple sequences. Several protein bands were found in the 65-72 KDa region, which specifically bind both poly [(dG-dT).(dA-dC)] and a natural fragment containing 40 bp of this sequence. These proteins do not bind to homopolymers poly [(dA).(dT)] and poly [(dG-dA).(dC-dT)], or other foreign DNAs.