EMG1 (NEP1) methylates a pseudouridine residue in precursor rRNA (pre-rRNA) to yield N(1)-methylpseudouridine (Wurm et al. 2010 and inferred from the yeast homolog) in the nucleolus (Eschrich et al. 2002). Following further modification and nucleolytic processing, the N(1)-methylpseduouridine residue will become N1-methyl-N3-(3-amino-3-carboxypropyl) pseudouridine-1248 of the 18S rRNA. A mutation in EMG1 causes Bowen-Conradi Syndrome, which is characterized by growth retardation, microcephaly, severe psychomotor delay, and minor external abnormalities (Armistead et al. 2009). As inferred from the yeast homolog, EMG1 is a component of the small subunit processome (SSU processome) a large complex of proteins that binds the 5' region of pre-rRNA, processes and modifies the 18S rRNA, and assists the assembly of the small ribosomal subunit.