[Binding of human ribosomal protein p40 and its truncated mutants to the small ribosomal subunit].

Ribosomal protein SA (rpSA) or p40 is a structural element of the small subunit of the eukaryotic ribosome. N-terminal and central parts of the protein are homologous to prokaryotic rpS2 whereas its C-terminal part is eukaryote specific. In this study we showed that samples of 40S ribosomal subunits isolated from full-term human placenta are variably deficient in the rpSA content. To reveal rpSA ability to bind to human 40S ribosomal subunits, recombinant rpSA and its mutant forms with N- and C-terminal deletions have been synthesized. It was shown that both full-size and truncated from the N-terminus proteins were able to bind to the 40S subunits whereas the mutant truncated from C-terminus was not.