title: A major species of mammalian messenger RNA lacking a polyadenylate segment.
abstract: Translation of total polysomal RNA from sarcoma 180 ascites cells in a wheat germ cell-free system produces two major polypeptides, A and B, with molecular weights of 50,000 and 45,000, respectively. Fractionation on Millipore filters or on oligo(dT)-cellulose leads to retention of the mRNA specific for protein A in the poly(A)-containing fraction and to accumulation of the B mRNA in the unadsorbed poly(A)-deficient fraction. The mRNA for B sediments at approximately 18 S; it is released as a 50S ribonucleorprotein upon EDTA treatment of polysomes. Its translation is particularly sensitive to an inhibitor present in the polysomal RNA. The poly(A)-deficient mRNA for the 45,000 dalton polypeptide is also present in mouse myeloma MPC-11 cells, where it seems to be localized in membrane-bound polysomes.
mesh_terms: D000818:Animals; D002474:Cell-Free System; D002498:Centrifugation; D051379:Mice; D008970:Molecular Weight; D009101:Multiple Myeloma / Q000032:analysis; D009194:Myeloma Proteins / Q000096:biosynthesis; D009363:Neoplasm Proteins / Q000096:biosynthesis; D011061:Poly A / Q000032:analysis*; D011132:Polyribosomes / Q000032:analysis; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000032:analysis* / Q000378:metabolism; D012334:RNA, Neoplasm / Q000032:analysis* / Q000378:metabolism; D012510:Sarcoma 180 / Q000032:analysis*; D013329:Structure-Activity Relationship; D014908:Triticum
chemical_list: D009194:Myeloma Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011061:Poly A