Small nucleolar RNA SNORD15

In molecular biology, SNORD15 (also known as U15) is a non-coding RNA (ncRNA) molecule which functions in the modification of small nuclear RNAs (snRNAs, also a type of ncRNAs). 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 (snoRNA) and also often referred to as a guide RNA.

Small nucleolar RNA SNORD15
Predicted secondary structure and sequence conservation of SNORD15
Identifiers
Symbol	SNORD15
Alt. Symbols	U15
Rfam	RF00067
Other data
RNA type	Gene; snRNA; snoRNA; CD-box
Domain(s)	Eukaryota
GO	GO:0005730 GO:0006396
SO	SO:0000593
PDB structures	PDBe

U15 belongs to the C/D box class of snoRNAs which contain the conserved sequence motifs known as the C box (UGAUGA) and the D box (CUGA). Most of the members of the box C/D family function in directing site-specific 2'-O-methylation of substrate RNAs.^[1] U15 is predicted to guide the 2'O-ribose methylation of 28S ribosomal RNA (rRNA) residue A3764.^[2][3]

In humans there are two closely related copies of the U15 snoRNA (called SNORD15A and SNORD15B). They are both encoded in the introns of the ribosomal protein S3.^[4] In Xenopus laevis it is located within the introns of ribosomal protein S1 ^[5]

snoR75 from Arabidopsis thaliana^[6] and homologues in rice Oryza sativa and other plants are alternatively known as U15, and, despite a significantly shorter sequence length, appear to be related.^[7]