Figure 11.

Schematic diagram of signaling pathways used by EGF to stimulate goblet cell proliferation. Src could interact with PI-3K before or after its activation. AKT interacts with the ERK1/2 pathway at an unknown step. EGF, epidermal growth factor; EGF receptor, epidermal growth factor receptor; PLCγ1, phospholipase C gamma1; PKCα, protein kinase C alpha; Pyk2, a nonreceptor tyrosine kinase; Src, a nonreceptor tyrosine kinase; PI-3K, phosphoinositide 3-kinase; AKT, serine/threonine-specific protein kinase; Shc, adaptor protein; Grb2, adaptor protein; Ras, a GTPase; Raf, mitogen-activated protein kinase kinase kinase; MEK, mitogen-activated protein kinase kinase; ERK1/2, extracellular regulated kinase 1/2, also known as mitogen-activated protein kinase.