Mcl-1( Myeloid cell leukemia 1) is an anti-apoptotic member of the Bcl-2 family originally isolated from the ML-1 human myeloid leukemia cell line during phorbol ester-induced differentiation along the monocyte/macrophage pathway. Mcl-1 is an important and specific regulator that is necessary for the homeostasis of early hematopoietic progenitors. Mcl-1 is phosphorylated in response to treatment with phorbol ester, microtubule-damaging agents, oxidative stress, and cytokine withdrawal . Phosphorylation at Thr163, the conserved MAP kinase/ERK site located within the PEST region, slows Mcl-1 protein turnover but may prime the GSK-3 mediated phosphorylation at Ser159 that leads to Mcl-1 destabilization.
