Casein synthesis by mouse polysomes and their messenger ribonucleic acid extracts.
Mammary epithelial cells from lactating mice were used to compare the in vitro casein synthesis by membrane-bound and free polysomes with that of messenger ribonucleic acid extracted from free- and bound polysomes (polysomal system and a rabbit reticulocyte lysate system). Casein synthesis was detected by incorporation of hydrogen-3 labeled amino acids in the reaction mixture into synthesized casein molecules. Membrane-bound polysomes synthesized considerably more casein than free polysomes; this difference was abolished by deoxycholate treatment of free polysomes. The synthesizing activity of messenger ribonucleic acid was similar whether extracted from free- or membrane-bound polysomes. Casein synthesis may be controlled by factors on the polysomal membrane.
D000818:Animals; D002364:Caseins / Q000096:biosynthesis*; D002474:Cell-Free System; D005260:Female; D007774:Lactation; D008321:Mammary Glands, Animal; D051379:Mice; D011132:Polyribosomes / Q000378:metabolism*; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism*; D012335:RNA, Ribosomal / Q000378:metabolism*; D011817:Rabbits; D012156:Reticulocytes / Q000378:metabolism
D002364:Caseins; D012333:RNA, Messenger; D012335:RNA, Ribosomal