Protein sprouty homolog 4 is a protein that in humans is encoded by the SPRY4 gene.
SPRY4 is an inhibitor of the receptor-transduced mitogen-activated protein kinase (MAPK) signaling pathway. It is positioned upstream of RAS (see HRAS; MIM 190020) activation and impairs the formation of active GTP-RAS (Leeksma et al., 2002).
SPRY4 has been shown to interact with TESK1.