Cell-free synthesis of mouse corticotropin. Evidence for two high molecular weight gene products.
Polysomes or mRNA prepared from cultured AtT-20/D16v mouse pituitary adenocarcinoma cells direct the efficient incorporation of amino acid into newly synthesized material in the presence of wheat germ translational factors. A significant franction of the total cell-free product is specifically immunoprecipitable with corticotropin antibody purified by immune affinity chromatography. Analysis of the cell-free synthesized immunoreactive products by sodium dodecyl sulfate-polyacrylamide gel electrophoresis reveals that two high molecular weight corticotropin species (Mr congruent to 32,500 and 28,000) are synthesized in an approximate 2:1 ratio. Neither product contains carbohydrate based upon concanavalin A chromatography or exposure to polysaccharidases. The smaller molecular weight product does not appear to arise from proteolytic processing since both species are synthesized in approximately the same ratio in cell-free reaction mixtures directed by either polysomes or mRNA. These results suggest that AtT-20/D16v cells contain two distinct mRNA poluations specifying the synthesis of two different high molecular weight forms of mouse corticotropin.
D000230:Adenocarcinoma / Q000378:metabolism; D000324:Adrenocorticotropic Hormone / Q000096:biosynthesis*; D000818:Animals; D002460:Cell Line; D051379:Mice; D008970:Molecular Weight; D010911:Pituitary Neoplasms / Q000378:metabolism; D011132:Polyribosomes / Q000378:metabolism; D014176:Protein Biosynthesis / Q000187:drug effects; D011691:Puromycin / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism
D012333:RNA, Messenger; D011691:Puromycin; D000324:Adrenocorticotropic Hormone