Tyrosine kinase substrate that inhibits growth-factor-mediated activation of MAP kinase (By similarity). Negatively regulates hematopoiesis of bone marrow (By similarity). Inhibits fibroblast growth factor (FGF)-induced retinal lens fiber differentiation, probably by inhibiting FGF-mediated phosphorylation of ERK1/2 (By similarity). Attenuates actin stress fiber formation via inhibition of TESK1-mediated phosphorylation of cofilin (PubMed:18216281). Inhibits TGFB-induced epithelial-to-mesenchymal transition in lens epithelial cells (By similarity). Homodimer and heterodimer (PubMed:15683364). Able to interact with SPRED2 to form heterodimers (PubMed:15683364). Interacts (via C-terminus) with TAOK1/MARKK (via C-terminus); the interaction does not affect TAOK1 kinase activity (PubMed:18216281). Interacts (via C-terminus) with TESK1 (via C-terminus); the interaction inhibits TESK1 kinase activity (PubMed:18216281). Interacts with CAV1 (PubMed:16115197). Interacts with RAS (By similarity). Interacts with palmitoyltransferase ZDHHC17/HIP14; the interaction leads to palmitoylation of SPRED1 (PubMed:24705354). Localized in cholesterol-rich membrane raft/caveola fractions. Weakly expressed in embryonic cell line HEK293. Palmitoylated by ZDHHC17/HIP14. Phosphorylated on tyrosine. Ubiquitinated. The disease is caused by variants affecting the gene represented in this entry. Contaminating sequence. Potential poly-A sequence.