Ribosomes translate genetic information from messenger RNA into proteins, and are therefore necessary for cell growth. Disruption of ribosome biogenesis leads to arrest in cell growth and replication, and has been identified as a precursor to some cancers. Eukaryotic ribosomes are composed of 40S and 60S subunits. The 40S subunit includes one segment of ribosomal RNA and approximately 30 proteins. The 60S subunit is composed of three segments of rRNA and approximately 50 proteins. Both are necessary to translate proteins from mRNA. NOM1 was identified by the Conklin lab because of its location at a breakpoint on chromosome 7 associated with acute myeloid leukemia. Functional studies of NOM1 have demonstrated that it: is required for cell growth and cell replication; localizes to the nucleolus; interacts with and targets several proteins to the nucleolus including Protein Phosphatase I, the oncogene MSP58 and the RNA helicase eIF4AIII; is required for production of 40S ribosomes.