DNA-RNA hybrids from ovaries of normal and sterilized Musca domestica

Abstract

DNA and C 14-labelled RNA were isolated from normal and thiotepa-sterilized ovaries of houseflies ( Musca domestica). The two forms of nucleic acid were obtained during different stages of oögenesis. RNA-DNA hybrids were prepared by hybridization of RNA with DNA immobilized on membrane filters. The degrees of hybridization of homologous and heterologous forms were determined by assaying the C 14-labelled RNA incorporated into the RNA-DNA hybrids. The RNA from normal and sterilized fly ovaries hybridized with the homologous DNA to about the same degree. However, with heterologous hybrids, that is, RNA from one type of ovary and DNA from the other, there was a lesser degree of hybridization indicating that only a portion of the RNA was able to recognize complementary sites in the heterologous DNA.