Protein sprouty homolog 4 (Spry4)

Suppresses the insulin receptor and EGFR-transduced MAPK signaling pathway, but does not inhibit MAPK activation by a constitutively active mutant Ras. Probably impairs the creation of GTP-Ras (By similarity).

Inhibits Ras-independent, but not Ras- dependent, activation of RAF1 (By similarity). .