PRPF38A is a pre-mRNA splicing factor that functions as a component of the U2-type spliceosome, a ribonucleoprotein complex essential for mRNA processing 1. The protein localizes to nuclear speckles, dynamic nuclear bodies involved in splicing regulation, where it forms droplet-like structures and physically interacts with MFAP1 2. PRPF38A's spatial organization within the nucleus regulates splicing activity; relocation of PRPF38A to the nuclear lamina induces intron retention, demonstrating that subcellular localization controls splicing factor function 3. Clinically, PRPF38A represents a vulnerability in basal-A triple-negative breast cancer cells; knockdown of PRPF38A causes widespread intron retention in genes critical for protein homeostasis, mitosis, and apoptosis, and splicing inhibition shows therapeutic potential when combined with proteasome inhibitors 1. Additionally, genomic variants near PRPF38A influence its expression and are associated with pediatric bone accrual, suggesting roles in osteoblast differentiation and bone development 4. These findings position PRPF38A as both a fundamental splicing regulator and a potential therapeutic target in cancer and skeletal diseases.