H/ACA ribonucleoprotein complex, subunit Nhp2, eukaryote (IPR002415)

Short name: H/ACA_rnp_Nhp2_euk

Family relationships


H/ACA ribonucleoprotein particles (RNPs) are a family of RNA pseudouridine synthases that specify modification sites through guide RNAs. More than 100 mammalian H/ACA RNAs form an equal number of ribonucleoproteins (RNPs) by associating with the same four core proteins: Cbf5, Gar1, Nhp2 and Nop10. The function of these H/ACA RNPs is essential for biogenesis of the ribosome, splicing of precursor mRNAs (pre-mRNAs), maintenance of telomeres and probably for additional cellular processes [PMID: 16647858]. Recent crystal structures of archaeal H/ACA protein complexes show how the same four proteins accommodate >100 distinct but related H/ACA RNAs [PMID: 16943774]. The complex contains a stable core composed of Cbf5 and Nop10, to which Gar1 and Nhp2 subsequently bind, the complex interacts with snoRNAs [PMID: 19917616].

Nhp2 is part of a complex which catalyzes pseudouridylation of rRNA and is required for rRNA biogenesis. This involves the isomerization of uridine such that the ribose is subsequently attached to C5, instead of the normal N1. Pseudouridine ("psi") residues may serve to stabilise the conformation of rRNAs. Nph2 directly binds H/ACA snoRNAs. Nhp2 belongs to the ribosomal protein L7Ae family.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0003723 RNA binding

Cellular Component

GO:0005730 nucleolus

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.