The box H/ACA ribonucleoproteins (RNPs) are protein-RNA complexes responsible for pseudouridylation, the most abundant post-transcriptional modification of cellular RNAs []. Each distinct H/ACA RNA assembles with a common set of four proteins, Cbf5 (NAP57 in rodents and dyskerin in humans), Nop10, Nhp2 (L7Ae in archaea) and Gar1 []. Shq1 is an essential assembly factor for H/ACA ribonucleoproteins (RNPs) required for ribosome biogenesis, pre-mRNA splicing, and telomere maintenance []. It interacts with Cbf5 and may function as an assembly chaperone that protects the Cbf5 protein complexes from non-specific RNA binding and aggregation before assembly of H/ACA RNA [].
This conserved region identifies a set of hypothetical protein sequences from the Metazoa and Ascomycota which include SHQ1 from Saccharomyces cerevisiae.
