SF3B4 : splicing factor 3b subunit 4
Description
The SF3B4 (splicing factor 3b subunit 4) is a protein-coding gene located on chromosome 1.
The SF3B4 gene provides instructions for making the SAP49 protein, which is part of a complex called a spliceosome. Spliceosomes help process messenger RNA (mRNA), which is a chemical cousin of DNA that serves as a genetic blueprint for making proteins. The spliceosomes recognize and then remove regions from mRNA molecules that are not used in the blueprint (which are called introns). The SAP49 protein may also be involved in a chemical signaling pathway known as the bone morphogenic protein (BMP) pathway. This signaling pathway regulates various cellular processes and is involved in the growth of cells. The SAP49 protein is particularly important for the maturation of cells that build bones and cartilage (osteoblasts and chondrocytes).
Component of the 17S U2 SnRNP complex of the spliceosome, a large ribonucleoprotein complex that removes introns from transcribed pre-mRNAs. The 17S U2 SnRNP complex directly participates in early spliceosome assembly and mediates recognition of the intron branch site during pre-mRNA splicing by promoting the selection of the pre-mRNA branch-site adenosine, the nucleophile for the first step of splicing. Within the 17S U2 SnRNP complex, SF3B4 is part of the SF3B subcomplex, which is required for 'A' complex assembly formed by the stable binding of U2 snRNP to the branchpoint sequence in pre-mRNA. Sequence independent binding of SF3A and SF3B subcomplexes 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. Also acts as a component of the minor spliceosome, which is involved in the splicing of U12-type introns in pre-mRNAs. {ECO:0000269|PubMed:10882114, ECO:0000269|PubMed:12234937, ECO:0000269|PubMed:15146077, ECO:0000269|PubMed:27720643, ECO:0000269|PubMed:32494006, ECO:0000269|PubMed:33509932}
SF3B4 is also known as AFD1, Hsh49, SAP49, SF3b49.