Protein: Splicing factor U2AF 26 kDa subunit (U2 auxiliary factor 26) (U2 small nuclear RNA auxiliary factor 1-like protein 4) (U2AF1-like 4) (Q8BGJ9)
Organism: Mus musculus (Mouse)
Function: RNA-binding protein that function as a pre-mRNA splicing factor. Plays a critical role in both constitutive and enhancer-dependent splicing by mediating protein-protein interactions and protein-RNA interactions required for accurate 3'-splice site selection. It can functionally substitute for U2AF1 in constitutive splicing and enhancer-dependent splicing. Acts by enhancing the binding of U2AF2 to weak pyrimidine tracts. Also participates in the regulation of alternative pre-mRNA splicing. Activates exon 5 skipping of PTPRC during T-cell activation; an event reversed by GFI1. Binds to RNA at the AG dinucleotide at the 3'-splice site. Shows a preference for AGC or AGA. Alternative splicing of U2AF1L4 may play a role in connecting the circadian rhythm to changing external cues: may provide a circadian buffering system in central and periphery clocks that allows synchronized adaption to clock-resetting stimuli in order to prevent potentially pathogenic desynchronization.
Subcellular location: [Isoform 1]: Nucleus {ECO:0000269|PubMed:11739736, ECO:0000269|PubMed:18460468}. Nucleus speckle {ECO:0000269|PubMed:11739736}. Cytoplasm {ECO:0000269|PubMed:16819553, ECO:0000269|PubMed:18460468, ECO:0000269|PubMed:24837677}. Note=Interaction with C1QBP is required for the nuclear translocation. Displays active nucleo-cytoplasmic shuttling. {ECO:0000269|PubMed:18460468}.; SUBCELLULAR LOCATION: [Isoform 3]: Cytoplasm {ECO:0000269|PubMed:18460468, ECO:0000269|PubMed:24837677}.; SUBCELLULAR LOCATION: [Isoform 2]: Cytoplasm {ECO:0000269|PubMed:18460468}.
Sequence: MAEYLASIFGTEKDKVNCSFYFKIGACRHGDRCSRLHNKPTFSQTIVLLNLYRNPQNTAQTADGSHCHVSDVEVQEHYDNFFEEVFTELQEKYGEIEEMNVCDNLGDHLVGNVYVKFRREEDAERAVAELNNRWFNGQAVHAELSPVTDFRESCCRQYEMGECTRGGFCNFMHLRPISRNLRRQLYGRGPRHRSPPRSHTGHRPRERNRRRSPDHRHGRF
InterPro domains: - IPR035979: RNA-binding domain superfamily (homologous_superfamily) [44-145]
- IPR012677: Nucleotide-binding alpha-beta plait domain superfamily (homologous_superfamily) [43-146]
- IPR000504: RNA recognition motif domain (domain) [65-147]
- IPR000571: Zinc finger, CCCH-type (domain) [12-176]
- IPR003954: RNA recognition motif domain, eukaryotic-type (domain) [66-143]
- IPR009145: U2 auxiliary factor small subunit (family) [1-216]
Interaction partners: - Splicing factor U2AF 65 kDa subunit
- Splicing factor U2AF 35 kDa subunit
- Splicing factor 1
- Serine/arginine-rich splicing factor 2
- Serine/arginine-rich splicing factor 5
- Serine/arginine-rich splicing factor 1
- Serine/arginine-rich splicing factor 3
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0005515 (protein binding), GO:0019904 (protein domain specific binding)
Biological Process (BP): GO:0008150 (biological process), GO:0032502 (developmental process), GO:0009987 (cellular process), GO:0048869 (cellular developmental process), GO:0048856 (anatomical structure development), GO:0030154 (cell differentiation), GO:0048468 (cell development), GO:0002244 (hematopoietic progenitor cell differentiation), GO:0030097 (hemopoiesis)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0043229 (intracellular organelle), GO:0043227 (membrane-bounded organelle), GO:0043231 (intracellular membrane-bounded organelle), GO:0005634 (nucleus)