May play a role in mRNA degradation (Probable). Endonuclease required for processing of 20S pre-rRNA precursor and biogenesis of 40S ribosomal subunits (By similarity). Interacts with UPF2 (Probable). Component of the small ribosomal subunit, ribosomal RNA processing complex (SSU RRP complex) (PubMed:15231747). Detected in liver, lung, placenta, endothelial cells and spleen. Belongs to the NOB1 family.