RNases H are enzymes that specifically hydrolyse RNA when annealed to a complementary DNA and are present in all living organisms. In yeast RNase H2 is composed of a complex of three proteins (Rnh2Ap, Ydr279p and Ylr154p), this family represents the homologues of Ydr279p [1]. It is not known whether non yeast proteins in this family fulfil the same function. This domain corresponds to the N-terminal triple barrel domain.

1: RNase H2 of Saccharomyces cerevisiae is a complex of three proteins. Jeong HS, Backlund PS, Chen HC, Karavanov AA, Crouch RJ; Nucleic Acids Res. 2004;32:407-414. PMID:14734815