Predicted to be involved in endonucleolytic cleavage in ITS1 to separate SSU-rRNA from 5.8S rRNA and LSU-rRNA from tricistronic rRNA transcript (SSU-rRNA, 5.8S rRNA, LSU-rRNA) and ribosomal large subunit biogenesis. Predicted to be located in nucleolus. Predicted to be part of preribosome, large subunit precursor. Is an ortholog of human RRS1 (ribosome biogenesis regulator 1 homolog).