Binding of mRNA by an oligopeptide containing an evolutionarily conserved sequence from RNA binding proteins

Several proteins with an affinity to RNA contain a conserved sequence of 8 amino acids which is postulated as being important for RNA binding. An oligopeptide of 11 amino acids containing this sequence is shown to bind 32P-labelled globin mRNA in a filter binding assay. High concentrations of heparin compete for this binding. 10 other peptides with different sequences do not exhibit affinity to RNA in this assay. These results support the relevance of the conserved peptide sequence in the binding of proteins to RNA.