UniProt functional annotation for Q15427

UniProt code: Q15427.

Organism: Homo sapiens (Human).
Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.
 
Function: Subunit of the splicing factor SF3B required for 'A' complex assembly formed by the stable binding of U2 snRNP to the branchpoint sequence (BPS) in pre-mRNA. Sequence independent binding of SF3A/SF3B complex upstream of the branch site is essential, it may anchor U2 snRNP to the pre-mRNA. May also be involved in the assembly of the 'E' complex. SF3B4 has been found in complex 'B' and 'C' as well. Belongs also to the minor U12- dependent spliceosome, which is involved in the splicing of rare class of nuclear pre-mRNA intron.
 
Subunit: Component of splicing factor SF3B complex which is composed of at least eight subunits; SF3B1, SF3B2, SF3B3, SF3B4, SF3B5, SF3B6, PHF5A/SF3B14B, and DDX42/SF3B125. SF3B associates with the splicing factor SF3A and a 12S RNA unit to form the U2 small nuclear ribonucleoproteins complex (U2 snRNP). Component of the U11/U12 snRNPs that are part of the U12-type spliceosome. SF3B4 interacts directly with SF3B2. {ECO:0000269|PubMed:12234937, ECO:0000269|PubMed:12738865, ECO:0000269|PubMed:15146077}.
Subcellular location: Nucleus {ECO:0000250}.
Disease: Acrofacial dysostosis 1, Nager type (AFD1) [MIM:154400]: A form of acrofacial dysostosis, a group of disorders which are characterized by malformation of the craniofacial skeleton and the limbs. The major facial features of AFD1 include downslanted palpebral fissures, midface retrusion, and micrognathia, the latter of which often requires the placement of a tracheostomy in early childhood. Limb defects typically involve the anterior (radial) elements of the upper limbs and manifest as small or absent thumbs, triphalangeal thumbs, radial hyoplasia or aplasia, and radioulnar synostosis. Phocomelia of the upper limbs and, occasionally, lower-limb defects have also been reported. {ECO:0000269|PubMed:22541558}. Note=The disease is caused by mutations affecting the gene represented in this entry.
Similarity: Belongs to the SF3B4 family. {ECO:0000305}.
Similarity: Contains 2 RRM (RNA recognition motif) domains. {ECO:0000255|PROSITE-ProRule:PRU00176}.

Annotations taken from UniProtKB at the EBI.