To begin to define the earliest events in T-cell development, we have examined the in vivo function of FLT3 using a mouse knock-in strategy. However, the nature of the first positive-feedback interaction between LCK and FLT3 has not been established and, consequently, the role of FLT3 has remained ambiguous. The earliest contacts between the T-cell receptors and the helper cytokine receptors are mediated by a combination of signaling molecules, such as LCK, ZAP-70, PLC gamma, PYK2, and FLT3. These events determine whether T-cell development will proceed or be arrested at a particular stage. These interactions occur between germ-line encoded receptors present at the surface of developing T cells (membrane proximal signals) and protein tyrosine kinase-coupled receptors expressed later on the T-cell surface (membrane distal signals). Helper T-cell development involves a series of sequential positive-feedback interactions between cell-surface receptors.
Category:Unmanned aerial vehiclesA novel positive-feedback interaction of lymphoid-specific kinase (LSK) and FLT3 during the development of helper T cells.
