MK2 (MAPK-activated protein kinase 2), also known as MAPKAPK2, is a serine/threonine kinase in the MAPK signaling pathway. It consists of a kinase domain and is primarily located in the cytoplasm and nucleus. MK2 plays a crucial role in stress response, cell cycle regulation, and inflammation. It regulates the phosphorylation of various substrates such as Hsp27, ATF2, and TTP, affecting cytokine production, cell cycle progression, and apoptosis, through activation by p38 MAPK. The expression of MK2 is specific in different tissues and cells, and mutations or dysregulation in its gene expression are associated with various diseases, including cardiovascular diseases, cancer, and inflammatory disorders.