InterPro domain: IPR038514

This entry consists of the C-terminal domain of eukaryotic Aar2 and Aar2-like proteins. This domain consists of 9 alpha helices, 1 pi helix and 1 3(10)-helix.

Aar2 is a U5 small nuclear ribonucleoprotein (snRNP) particle assembly factor and part of Prp8, which forms a large complex containing U5 snRNA, Snu114, and seven Sm proteins (B, D1, D2, D3, E, F and G). Upon import of the complex into the nucleus, Aar2 phosphorylation leads to its release from Prp8 and replacement by Brr2p, thus playing an important role in Brr2p regulation and possibly safeguarding against non-specific RNA binding to Prp8 [ 1 , 2 , 3 , 4 , 5 ]. Aar2p binds directly with the RNaseH-like domain in the C-terminal region of Prp8p [ 6 ]. In yeast, Aar2 protein is involved in splicing pre-mRNA of the a1 cistron and other genes important for cell growth [ 7 ].

1. A snRNP's ordered path to maturity. Genes Dev. 25, 1563-7
2. Crystal structure of Prp8 reveals active site cavity of the spliceosome. Nature 493, 638-43
3. The yeast U5 snRNP coisolated with the U1 snRNP has an unexpected protein composition and includes the splicing factor Aar2p. RNA 7, 1554-65
4. Prp8p dissection reveals domain structure and protein interaction sites. RNA 12, 198-205
5. prp8 mutations that cause human retinitis pigmentosa lead to a U5 snRNP maturation defect in yeast. Nat. Struct. Mol. Biol. 14, 1077-83
6. Mechanism for Aar2p function as a U5 snRNP assembly factor. Genes Dev. 25, 1601-12
7. AAR2, a gene for splicing pre-mRNA of the MATa1 cistron in cell type control of Saccharomyces cerevisiae. Mol. Cell. Biol. 11, 5693-700