Immunological identification of a chromocenter-associated protein in polytene chromosomes of Drosophila

An antiserum directed against a non-histone chromosomal protein was found to stain preferentially the heterochromatic chromocenter of the polytene chromosomes of the salivary glands of several Drosophila species. The highly condensed α-heterochromatin stained most prominently. The chromocenter-associated antigen probably consists of a single polypeptide of molecular weight of 38000. This protein may play a role in the specific chromatin condensation of this chromosomal region.