Q99759 

MEKK3(MEK kinase 3) also known as MAP3K3 is a 626-amino acid polypeptide that is 96.5% identical to mouse Mekk3. MEKK3 plays a crucial role in mitogen-activated protein (MAP) kinase signaling pathways, which are essential for cellular responses to various extracellular stimuli, including growth factors. Specifically, MEKK3 is involved in phosphorylation and activation of downstream MAP kinases, such as ERK, JNK, and p38, which are pivotal for regulating processes like cell proliferation, differentiation, and survival. Precise regulation of these pathways is vital for maintaining normal cellular functions and preventing diseases such as cancer, where aberrant signaling can lead to uncontrolled cell growth.