Partial Purification of a Progesterone-Inducible Messenger RNA (Avidin) from Hen Oviduct

Publisher Website
Google Scholar
Abstract
The mRNA for avidin, which represents less than 0.05% of the total cellular proteins, was partially purified from hen oviduct, and the presence of avidin mRNA depended upon prior stimulation by progesterone. A total nucleic acid extract was subjected to oligo (dT)-cellulose chromatography, followed by Sepharose 4B chromatography, preparative agarose gel electrophoresis and sucrose gradient centrifugation. The relative purity of each preparation was assessed by translation in a wheat-germ system; avidin mRNA activity was measured by specific immunoprecipitation of synthesized proteins. Avidin mRNA was separated from the bulk of the total mRNA activity of the oviduct and from all rRNAs to produce greater than a 1000-fold enrichment of avidin mRNA activity compared with total cellular RNA. Based on the translation assay, the most highly purified fraction contained about 2.5% avidin mRNA. Avidin mRNA activity was absent in partially purified mRNA obtained from estrogen-stimulated chick oviducts, but was detected in oviducts following progesterone administration.