MEKs, commonly known as "Mitogen-Activated Protein Kinase Kinases," refers to a group of enzymes that play a crucial role in various intracellular signaling pathways. They specifically function as intermediates between the activation of cell surface receptors, also known as mitogens, and the subsequent regulation of cellular responses such as cell division, proliferation, differentiation, and apoptosis.
MEKs are a type of protein kinase responsible for activating another group of enzymes called mitogen-activated protein kinases (MAPKs). Upon stimulation by extracellular signals or growth factors, MEKs are activated through phosphorylation and subsequently phosphorylate specific residues of MAPKs. These activated MAPKs then translocate into the cell nucleus, where they modulate the activity of target proteins by phosphorylation, leading to the activation or suppression of various signaling pathways.
The MEK proteins are characterized by their conserved domains, including an N-terminal regulatory domain and a C-terminal catalytic domain. They are typically found in eukaryotic cells and can be further classified into different isoforms, such as MEK1 and MEK2, based on their structural and functional characteristics.
MEKs are crucial components of numerous signaling cascades, such as the extracellular signal-regulated kinase (ERK) pathway, c-Jun N-terminal kinase (JNK) pathway, and p38 MAPK pathway. Dysregulation of MEK activity and signaling has been associated with several human diseases, including cancer, inflammatory disorders, and neurodegenerative diseases.
In summary, MEKs are enzymes that act as intermediates in cellular signaling pathways, connecting extracellular signals to specific intracellular responses. Their activation and subsequent phosphorylation of MAPKs lead to the modulation of cellular processes, making them essential components in
