SPHINX31

SPHINX31 is a potent and highly selective small molecule inhibitor of Serine/arginine protein kinase 1 (SRPK1). SRPK1 is a key kinase responsible for the phosphorylation of serine/arginine-rich (SR) proteins, which are essential regulators of alternative mRNA splicing. By binding to the ATP-binding pocket of SRPK1, SPHINX31 prevents the phosphorylation of these splicing factors, thereby modulating the production of various protein isoforms involved in angiogenesis, oncogenesis, and viral replication. In the context of oncology, SPHINX31 has been investigated for its ability to rewire the transcriptomic and splicing landscape of cervical cancer cells, showing differential effects based on human papillomavirus (HPV) status. It was originally developed by researchers at the University of Nottingham and has been used extensively as a chemical probe to study the role of SRPK1 in diseases such as cancer and neovascular eye disorders.