It is shown that the nucleotide sequences of archeal tRNAs correspond to pe
ptide sequences, some of which resemble very much the contemporary regulato
ry peptides. In particular, the nucleotide sequence of archeal A0980 tRNA(A
la) corresponds to a putative polypeptide, which is homologous to thymopoie
tin, a peptide hormone produced in thymus and endowed with immunomodulatory
activity. The 23 amino acid long synthetic peptide corresponding to A0980
interacts strongly with TAR RNA fragment of HIV mRNAs as well as binds spec
ifically to tRNA(Phe), whereas tRNA(Leu) and tRNA(Met) are deprived of such
ability.