Editing Mast cell (section)

===Degranulation and fusion===
An important adaptor protein activated by the Syk phosphorylation step is the [[linker for activation of T cells]] (LAT). LAT can be modified by phosphorylation to create novel binding sites.<ref name=pmid12217392/> [[PLCG1|Phospholipase C gamma]] (PLCγ) becomes phosphorylated once bound to LAT, and is then used to catalyze phosphatidylinositol bisphosphate breakdown to yield [[inositol trisphosphate]] (IP3) and [[diacyglycerol]] (DAG). IP3 elevates calcium levels, and DAG activates [[protein kinase C]] (PKC). This is not the only way that PKC is made. The tyrosine kinase [[FYN]] phosphorylates [[GAB2|Grb2-associated-binding protein 2]] (Gab2), which binds to [[PI3K|phosphoinositide 3-kinase]], which activates PKC. PKC leads to the activation of myosin light-chain phosphorylation granule movements, which disassembles the actin–myosin complexes to allow [[granule (cell biology)|granule]]s to come into contact with the plasma membrane.<ref name="Role of Mast Cells"/> The mast cell granule can now [[lipid bilayer fusion|fuse]] with the plasma membrane. Soluble N-ethylmaleimide sensitive fusion attachment protein receptor [[SNARE]] complex mediates this process. Different SNARE proteins interact to form different complexes that catalyze fusion. [[Rab (G-protein)|Rab3]] guanosine triphosphatases and Rab-associated kinases and phosphatases regulate granule membrane fusion in resting mast cells.