期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1973
卷号：70
期号：8
页码：2350-2355
DOI：10.1073/pnas.70.8.2350
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Release of formylmethionine from the reticulocyte ribosomal substrate, f[3H]Met-tRNA{middle dot}ribosome, is promoted by reticulocyte release factor (RF). The initial rate of this reaction is stimulated by GTP but inhibited by GDPCP. Formation of an RF{middle dot}UA[3H]A2{middle dot}ribosome complex is a measure of the binding of reticulocyte RF to the ribosome, and the recovery of this complex is increased by GDPCP and, to a lesser extent, GTP. These studies suggest that GTP is involved in the initial association of RF with the ribosome and that hydrolysis of the {gamma}-phosphate of the guanine nucleotide is required at a subsequent rate-limiting step. The ribosomal-dependent fMet-tRNA hydrolysis and GTPase activities of reticulocyte RF are inhibited when elongation factor (EF)-2 is bound to the respective ribosomal substrate in the presence of fusidic acid and GDP. When EF-G is bound to the f[3H]Met-tRNA{middle dot}AUG{middle dot}ribosome substrate with fusidic acid and GDP, the fMet-tRNA hydrolysis activity of Escherichia coli RF-1 and RF-2 is also inhibited. The binding of reticulocyte RF and E. coli RF-1 or RF-2 to their respective ribosomes is prevented when fusidic acid{middle dot}EF-2/EF-G{middle dot}GDP{middle dot}ribosome complexes are used.
