Description

The Src family tyrosine kinase p56^Lck (LCK) is a non-receptor tyrosine kinase that is primarily expressed in T cells and NK cells. It plays a critical role in T cell selection and maturation within the thymus, and also in the function of mature T cells. LCK, which is constitutively bound to cytosolic domains of CD4 and CD8 surface receptors, plays an essential role in T cell receptor (TCR) signaling. Engagement of the TCR with peptide antigen-loaded MHC complex results in the recruitment of CD4- and CD8-bound LCK to the TCR/CD3 signaling complex. LCK then transphosphorylates TCR-gamma chains and CD3 subunits, thereby activating the TCR/CD3 signaling pathway and leading to the recruitment and subsequent phosphorylation of Zap70 by LCK. LCK also plays an important role in interleukin-2 signaling that regulates the T cell proliferative response. Phosphorylation of LCK by CSK at Tyrosine 505 negatively regulates LCK, and is proposed to generate a closed, inactive conformation of the protein.

Formulation

Recommended Usage

Each lot of this antibody is quality control tested by intracellular flow cytometry using our True-Phos™ Perm Buffer in Cell Suspensions Protocol. For flow cytometric staining, the suggested use of this reagent is ≤ 0.25 µg per million cells in 100 µl volume. It is recommended that the reagent be titrated for optimal performance for each application.