title: The ribonucleic acids of the mammary gland of the guinea pig.
abstract: 1. 32-P-labelled polyribosome preparations were made from the mammary glands of lactating and late-pregnant guinea pigs after injection of (32-P)i into the animals. 2. The RNA of polyribosomes, ribosomal subunits and that released from polyribosomes by EDTA were analysed by zone velocity centrifugation and by polyacrylamide-gel electrophoresis. 3. RNA species which have the physical properties expected for the milk protein mRNA were detected. RNA species of a size which could code for the caseins were present in lactating but not in pre-lactating mammary-gland polyribosomes.
mesh_terms: D000818:Animals; D002364:Caseins; D002499:Centrifugation, Density Gradient; D004492:Edetic Acid; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006168:Guinea Pigs; D007774:Lactation; D008321:Mammary Glands, Animal / Q000032:analysis*; D010761:Phosphorus Radioisotopes; D011132:Polyribosomes / Q000032:analysis; D011247:Pregnancy; D012333:RNA, Messenger / Q000032:analysis; D012335:RNA, Ribosomal / Q000032:analysis*
chemical_list: D002364:Caseins; D010761:Phosphorus Radioisotopes; D012333:RNA, Messenger; D012335:RNA, Ribosomal; D004492:Edetic Acid