User:Htafer/SCARNA12

In molecular biology, Small Cajal body specific RNA 12 (also known as scaRNA12 or U89) is a small nucleolar RNA found in Cajal bodies. It is predicted to modify residue 46 in U5 spliceosomal RNA.

scaRNAs are a specific class of small nucleolar RNAs that localise to the Cajal bodies and guide the modification of RNA polymerase II transcribed spliceosomal RNAs U1, U2, U4, U5 and U12.

U89 is composed of a H/ACA box box domain and a C/D box domain. Its length ranges from 235 nt in Echinops to 283 nt in Monodelphis. U89, which is hosted solely in an intron of prohibitin 2, is not found beyond Theria, indicating that it might be a recent innovation.