RRNA small subunit pseudouridine methyltransferase Nep1 (, Nep1, nucleolar essential protein 1) is an enzyme with systematic name S-adenosyl-L-methionine:18S rRNA (pseudouridine<sup>1191</sup>-N<sup>1</sup>)-methyltransferase. This enzyme catalyses the following chemical reaction
This enzyme recognizes specific pseudouridine residues (Psi) in small subunits of ribosomal RNA based on the local RNA structure.
A point mutation in the ribosome biogenesis factor Nep1 impairs its nucleolar localisation and RNA binding and causes the Bowen-Conradi syndrome.
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