molecular biology Molecular biology is a branch of biology that seeks to understand the molecule, molecular basis of biological activity in and between Cell (biology), cells, including biomolecule, biomolecular synthesis, modification, mechanisms, and interactio ...

, Small nucleolar RNA R66 (also known as snoR66) is a

non-coding RNA A non-coding RNA (ncRNA) is a functional RNA molecule that is not Translation (genetics), translated into a protein. The DNA sequence from which a functional non-coding RNA is transcribed is often called an RNA gene. Abundant and functionally imp ...

(ncRNA) molecule which functions in the modification of other

small nuclear RNA Small nuclear RNA (snRNA) is a class of small RNA molecules that are found within the Cell nucleus#Splicing speckles, splicing speckles and Cajal body, Cajal bodies of the cell nucleus in eukaryotic cells. The length of an average snRNA is approxi ...

s (snRNAs). This type of modifying RNA is usually located in the

nucleolus The nucleolus (; : nucleoli ) is the largest structure in the cell nucleus, nucleus of eukaryote, eukaryotic cell (biology), cells. It is best known as the site of ribosome biogenesis. The nucleolus also participates in the formation of signa ...

of the eukaryotic cell which is a major site of snRNA biogenesis. It is known as a

small nucleolar RNA In molecular biology, small nucleolar RNAs (snoRNAs) are a class of small RNA molecules that primarily guide chemical modifications of other RNAs, mainly ribosomal RNAs, transfer RNAs and small nuclear RNAs. There are two main classes of snoRNA, t ...

(snoRNA) and also often referred to as a guide RNA. snoR66 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 Methylation, in the chemistry, chemical sciences, is the addition of a methyl group on a substrate (chemistry), substrate, or the substitution of an atom (or group) by a methyl group. Methylation is a form of alkylation, with a methyl group replac ...

of substrate RNAs. snoR66 was identified by a computational screening of the rice ''

Oryza sativa ''Oryza sativa'', having the common name Asian cultivated rice, is the much more common of the two rice species cultivated as a cereal, the other species being ''Oryza glaberrima, O. glaberrima'', African rice. It was History of rice cultivation ...

'' genome and is proposed to acts as a methylation guide for 18S ribosomal RNA in plants. Rice snoR66 has also been alternatively named snoZ269. Its should also not be confused with the snoRNA identified in yeast (''

Saccharomyces cerevisiae ''Saccharomyces cerevisiae'' () (brewer's yeast or baker's yeast) is a species of yeast (single-celled fungal microorganisms). The species has been instrumental in winemaking, baking, and brewing since ancient times. It is believed to have be ...

'') and called snR66.

References

External links

*
plant snoRNA database

yeast snoRNA database
Small nuclear RNA {{molecular-cell-biology-stub