InterPro domain: IPR034920

Rex proteins contain a 3'->5' exonuclease domain at their C terminus [ 1 ]. Rex4 has been characterized in S. cerevisiae, where it is involved in both ribosome assembly and pre-rRNA processing [ 2 ], particularly in the processing of Its1, the internal transcribed spacer localized between the 18S and 5.8S rRNAs [ 3 ].

1. Exoribonuclease superfamilies: structural analysis and phylogenetic distribution. Nucleic Acids Res. 29, 1017-26
2. Deletions in the S1 domain of Rrp5p cause processing at a novel site in ITS1 of yeast pre-rRNA that depends on Rex4p. Nucleic Acids Res. 30, 4222-31
3. The RNA catabolic enzymes Rex4p, Rnt1p, and Dbr1p show genetic interaction with trans-acting factors involved in processing of ITS1 in Saccharomyces cerevisiae pre-rRNA. RNA 10, 1946-56