Small nucleolar RNA SNORD46

In molecular biology, snoRNA U46 is a non-coding RNA molecule which functions in the modification of other small [nuclear RNA]s. This type of modifying RNA is usually located in the nucleolus of the eukaryotic cell which is a major site of snRNA biogenesis. It is known as a small nucleolar RNA and also often referred to as a guide RNA.
snoRNA U46 belongs to the C/D box class of snoRNAs which contain the conserved sequence motifs known as the C box and the D box. Most of the members of the box C/D family function in directing site-specific 2'-O-methylation of substrate RNAs.
U46 is encoded in intron 2 of the ribosomal protein S8 gene in human, and is hypothesised to guide methylation of 2'-O-ribose residues on 28S ribosomal RNA. The homologue of this snoRNA in Arabidopsis thaliana is called snoZ153. Some human U40 sequences have been annotated in the sequence databases as U46.