Cleavage of the HIV replication primer tRNALys,3 in human cells expressing bacterial anticodon nuclease

Anticodon nuclease is a bacterial restriction enzyme directed against tRNA(Lys). We report that anticodon nuclease also cleaves mammalian tRNA(Lys) molecules, with preference and site specificity shown towards the natural substrate. Expression of the anticodon nuclease core polypeptide PrrC in HeLa cells from a recombinant vaccinia virus elicited cleavage of intracellular tRNA(Lys),3. The data justify an inquiry into the possible application of anticodon nuclease as an inhibitor of tRNA(Lys),3-primed HIV replication. They also indicate that the anticodon region of tRNA(Lys) is a substrate recognition site and suggest that PrrC harbors the enzymatic activity.