Feline McDonough Sarcoma-like tyrosine kinase (FLT3) is a member of the class III tyrosine kinase receptor family. Ligand binding induces conformational changes in the FLT3 receptor, which facilitates its dimerization and autophosphorylation. Subsequently, tyrosine-protein kinase Fyn (FYN) associates with the phosphorylated residues of fully active FLT3 (Y591, Y599 and pY955) through its SH2 domain (Dosil et al. 1993, Chougule et al. 2016). Experiments confirming this event were performed in mouse cells.