Aurintricarboxylic acid inhibition of the binding of phenylalanyl-tRNAa to rat liver ribosomal subunits.
نویسنده
چکیده
Aurintricarboxylic acid (ATA) inhibits the initiation of protein synthesis in cell-free systems from both prokaryotes and eukaryotes at concentrations which do not affect chain elongation [ l-71 . We report here the effect of ATA on the poly U-dependent binding of Phe-tRNA to rat liver ribosomal subunits. ATA inhibits Phe-tRNA binding to 40 S subunits, catalysed by the rat liver cytosol initiation factor Ml (formerly called 40 S binding factor [8,9]). Binding to recombined 40 S and 60 S subunits, catalysed by elongation factor T-I, is inhibited to a similar extent; however, non-enzymic binding to subunits is inhibited to a greater extent. This unexpected differential inhibition appears to be due to the ability of enzymically inactive protein (present in the partially purified factor preparations) to bind ATA, reducing the amount of the latter available for inhibition of the binding of Phe-tRNA to ribosomes.
منابع مشابه
Evidence for one functional phenylalanyl-tRNA binding site on the 30S ribosomal subunit.
NH(2) terminal analysis of polyphenylalanine formed from 30S subunit-bound (14)C-phenylalanyl-tRNA suggests that there is only one site in a 30S subunit for specific binding of phenylalanyl-tRNA. Assuming that no movement of the bound phenylalanyl-tRNA takes place during association of 30S subunits with 50S ribosomal subunits, the binding site of the 30S ribosomal subunit corresponds to site 2 ...
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ورودعنوان ژورنال:
- FEBS letters
دوره 22 2 شماره
صفحات -
تاریخ انتشار 1972