Homo sapiens U85 scaRNA.
This RNA was cloned by Jády and Kiss (2001) from HeLa cells. It is composed of an H/ACA box domain and a C/D box domain, and is associated with both fibrillarin and Gar1p. It guides both the 2'-O-ribose methylation of the C45 residue of the U5 spliceosomal snRNA, and the pseudouridylation of the neighbouring U46 residue. U85 was subsequently shown to co-localize with coilin in Cajal bodies (Darzacq et al., 2002). Mutagenesis studies showed that U85 contains two copies of the Cajal body-specific localization signal, or CAB box (agAG), common to scaRNAs (Richard et al., 2003). The NMR structure of the U85 5' CAB box was determined by Theimer et al. (2007).