Nop56p (NOP56 ribonucleoprotein) is a yeast nucleolar protein that is part of a complex with the nucleolar proteins Nop58p and fibrillarin. Nop56p is required for assembly of the 60S ribosomal subunit and is involved in pre-rRNA processing. The protein encoded by NOP56 is similar in sequence to Nop56p and is also found in the nucleolus. Expansion of a GGCCTG repeat from 3-8 copies to 1500-2500 copies in an intron of this gene results in spinocerebellar ataxia 36. Multiple transcript variants encoding several different isoforms have been found for NOP56, but the full-length nature of most of them has not been determined.