Small nucleolar RNA SNORD44
snoRNA U44 is a non-coding RNA molecule which functions in the modification of other small nuclear RNAs. 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 U44 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.
U44 was originally cloned from HeLa cells and expression verified by northern blotting. It is predicted to guide 2'O-ribose methylation of 18S ribosomal RNA at residue A166. In the human genome, U44 is located in the same gene as several other C/D box snoRNAs.
