3'-5' RNA exonuclease that trims the 3' end of oligo(U) and oligo(A) tracts of the pre-U6 small nuclear RNA (snRNA) molecule, leading to the formation of a mature U6 snRNA 3' end-terminated with a 2',3'-cyclic phosphate (   ). Participates in the U6 snRNA 3' end processing that prevents U6 snRNA degradation (   ). In addition also removes uridines from the 3' end of U6atac snRNA and possibly the vault RNA VTRNA1-1 .
Subcellular locations: Nucleus