Differential synthesis of lens proteins in the presence of m7G(5')pppG and cleavage product m7GMP in an embryonic chick lens cell lysate.
The effect of m7GMP release from m7GMP-containing mRNA cap sequence m7GpppG by the embryonic chick lens m7GpppN-pyrophosphatase activity on the synthesis of lens proteins was examined in a newly developed homologous translation system derived from 15-day embryonic chick lenses. The synthesis of total lens polypeptides and delta-crystallin polypeptides, the major translation product, was inhibited 84% and 88%, respectively, by 0.5 mM m7GpppG; m7GMP (0.5 mM) inhibited total synthesis by 63% but was 33% less inhibitory toward delta-crystallin synthesis; GpppG and GMP were not inhibitors, m7GpppG inhibited met-tRNAfmet incorporation into 80S initiation complexes.
D000818:Animals; D002642:Chick Embryo; D003459:Crystallins / Q000096:biosynthesis*; D006150:Guanine Nucleotides / Q000494:pharmacology*; D006157:Guanosine Monophosphate / Q000494:pharmacology; D007908:Lens, Crystalline / Q000166:cytology / Q000378:metabolism*; D010441:Peptide Chain Elongation, Translational / Q000187:drug effects; D010442:Peptide Chain Initiation, Translational / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism*; D012343:RNA, Transfer / Q000378:metabolism
D003459:Crystallins; D006150:Guanine Nucleotides; D012333:RNA, Messenger; D006157:Guanosine Monophosphate; D012343:RNA, Transfer