Small Cajal body specific RNA 1

In molecular biology, Small Cajal body specific RNA 1 (also known as scaRNA1 or ACA35) is a small nucleolar RNA found in Cajal bodies and believed to be involved in the pseudouridylation of U2 spliceosomal RNA.

scaRNA1 is a non-coding RNA, which are functional products of gene but not translated into a protein. Such RNA molecules usually contain important secondary structure or ligand binding motifs and are involved in many important biological processes in the cell. More specifically, scaRNAs are a class of small nuclear RNAs that localise to the Cajal bodies and guide the modification of RNA polymerase II transcribed spliceosomal RNAs U1, U2, U4, U5 and U12.

scaRNA1 belongs to the H/ACA box class of guide RNAs, as it has the predicted hairpin-hinge-hairpin-tail structure, conserved H/ACA-box motifs and is found associated with GAR1 protein. It is predicted to guide pseudouridylation of the U2 spliceosomal RNA at residue U89.