RAI1 is homologous to Caenorhabditis elegans DOM-3 and human DOM3Z and binds to a nuclear exoribonuclease [1]. It is required for 5.8S rRNA processing [1]. Profile-profile comparison tools demonstrate this to be a PD-(D/E)XK nuclease, with a full set of canonical active site signature motifs characteristic to the PD-(D/E)XK nuclease superfamily [2].

1: Saccharomyces cerevisiae RAI1 (YGL246c) is homologous to human DOM3Z and encodes a protein that binds the nuclear exoribonuclease Rat1p. Xue Y, Bai X, Lee I, Kallstrom G, Ho J, Brown J, Stevens A, Johnson AW; Mol Cell Biol. 2000;20:4006-4015. PMID:10805743

2: Structure and function of the 5'-->3' exoribonuclease Rat1 and its activating partner Rai1. Xiang S, Cooper-Morgan A, Jiao X, Kiledjian M, Manley JL, Tong L; Nature. 2009;458:784-788. PMID:19194460