The function of this protein has been found, in Drosophila to inhibit branching of the trachea by antagonizing the BNL-FGF pathway. Also in Drosophila it is an antagonist of EGFR-mediated signaling in the eye. Most notably, in humans, it suppresses the insulin receptor and EGFR-transduced MAPK signaling pathway, but does not inhibit MAPK activation by a constitutively active mutant Ras. Sprouty inhibits of the Ras/mitogen-activated protein kinase (MAPK) cascade, a pathway crucial for developmental processes initiated by activation of various receptor tyrosine kinases. These proteins share a conserved, C-terminal cysteine-rich region, the SPR domain. This domain has been defined as a novel cytosol to membranetranslocation domain.[1][2][3][4] It has been found to be a PtdIns(4,5)P2-binding domain that targets the proteins to a cellular localization that maximizes their inhibitory potential.[2][5] It also mediates homodimer formation of these proteins.[1][5]
The SPR domain can occur in association with the WH1 domain (see INTERPRO) (located in the N-terminal part of the proteins) in the Spread proteins.
^Wakioka T, Sasaki A, Kato R, Shouda T, Matsumoto A, Miyoshi K, Tsuneoka M, Komiya S, Baron R, Yoshimura A (August 2001). "Spred is a Sprouty-related suppressor of Ras signalling". Nature. 412 (6847): 647–51. Bibcode:2001Natur.412..647W. doi:10.1038/35088082. PMID11493923. S2CID4345140.
^ abHanafusa H, Torii S, Yasunaga T, Nishida E (November 2002). "Sprouty1 and Sprouty2 provide a control mechanism for the Ras/MAPK signalling pathway". Nat. Cell Biol. 4 (11): 850–8. doi:10.1038/ncb867. PMID12402043. S2CID31064800.