SPR domain
In molecular biology the SPR domain is a protein domain found in the Sprouty and Spred proteins. These have been identified as inhibitors of the Ras/mitogen-activated protein kinase 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 membrane translocation domain. It has been found to be a PtdInsP2-binding domain that targets the proteins to a cellular localization that maximizes their inhibitory potential. It also mediates homodimer formation of these proteins.
The SPR domain can occur in association with the WH1 domain in the Spred proteins.