H/ACA ribonucleoprotein complex, subunit Gar1/Naf1 (IPR007504)

Short name: H/ACA_rnp_Gar1/Naf1

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].

This entry represents Gar1 and Naf1. Naf1 is an RNA-binding protein required for the maturation of box H/ACA snoRNPs complex and ribosome biogenesis. During assembly of the H/ACA snoRNPs complex, it associates with the complex, disappearing during maturation of the complex being replaced by GAR1 to yield mature H/ACA snoRNPs complex. Naf1 reveals a striking structural homology with the core domain of archaeal Gar1 [PMID: 17612558].

GO terms

Biological Process

GO:0001522 pseudouridine synthesis
GO:0042254 ribosome biogenesis

Molecular Function

No terms assigned in this category.

Cellular Component

No terms assigned in this category.

Contributing signatures

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