Pre-mRNA processing factor 8 (PRPF8) is a highly conserved core component of the spliceosome, the ribonucleoprotein complex responsible for pre-mRNA splicing in eukaryotic cells. PRPF8 is one of the largest and most central proteins within the U5 small nuclear ribonucleoprotein (snRNP) and plays a pivotal role in coordinating the catalytic steps of intron removal and exon ligation. It directly interacts with pre-mRNA, small nuclear RNAs (snRNAs), and multiple splicing factors, acting as a structural and functional scaffold for spliceosome assembly and activity. PRPF8 is ubiquitously expressed across tissues due to its essential role in gene expression. Mutations in PRPF8 have been strongly associated with retinitis pigmentosa (RP13), a degenerative retinal disease, highlighting its importance in tissue-specific splicing regulation. Additionally, altered PRPF8 function has been implicated in cancer, myelodysplastic syndromes, and other splicing-related disorders. As a key regulator of RNA processing, PRPF8 is central to transcriptome integrity and cellular homeostasis.