SF1(Splicing factor 1) also known as ZFP162, ZFM1 is a nuclear pre-mRNA splicing factor. SF1 plays a crucial role in the splicing process by specifically recognizing the seven-nucleotide branch point sequence located at 3′ splice sites, which is essential for the assembly of early spliceosomal complexes. This function is vital for accurate processing of pre-mRNA, influencing gene expression and cellular function. SF1 acts as a transcriptional repressor, potentially regulating proliferation and expression of pro-inflammatory gene products in smooth muscle cells. Expression of SF1 can be downregulated by cytokines, which may contribute to pathogenesis of hyperproliferative inflammatory diseases. SF1 includes a nuclear transport domain, a metal-binding motif, and regions rich in glutamine and proline, which are important for functional interactions.