INTERACTION OF HIV TAT PEPTIDES WITH TRNA(PHE) FROM YEAST

We present data on the interaction of arginine-rich peptides of human immunodeficiency virus (HIV-Tat) with tRNA(Phe) of Saccharomyces cerev isiae. We have found that tRNA forms complexes with the Tat1 peptide o f amino acid sequence GRKKRRQRRRA and its mutants where R is replaced by D-arginine, citrulline or ornithine. The structure of tRNA-Tat1 com plex was probed by specific RNases digestions and Pb2+-induced cleavag e of phosphodiester bond of guanosine. The nucleotide sequence UGGG lo cated in the dihydrouridine loop of tRNA(Phe) binds to Tat peptide and therefore is specifically protected against RNases and is not hydroly zed by Pb2+ ion. it seems that the peptide-RNA complex formation depen ds on direct recognition of guanine moieties of tRNA with arginine res idues. These interactions are similar to those observed in many DNA-pr otein complexes, but are different from those previously observed for TAR RNA-Tat complexes.