The function of UTP20 (UTP20 small subunit processome component, ENSG00000120800) is as follows. Part of the small subunit (SSU) processome, first precursor of the small eukaryotic ribosomal subunit. During the assembly of the SSU processome in the nucleolus, many ribosome biogenesis factors, an RNA chaperone and ribosomal proteins associate with the nascent pre- rRNA and work in concert to generate RNA folding, modifications, rearrangements and cleavage as well as targeted degradation of pre- ribosomal RNA by the RNA exosome. Involved in 18S pre-rRNA processing. Associates with U3 snoRNA. {ECO:0000269|PubMed:17498821, ECO:0000269|PubMed:34516797}.