Human Mcl-1 Antibody

MCL-1 (induced Myeloid Cell Leukemia differentiation protein 1; also Bcl2L3 and mcl1/EAT) is a 40-45 kDa member of the Bcl-2 family of proteins. It is widely expressed (in B cells, T cells, neutrophils and fibroblasts) and classified as a prosurvival Bcl-2 family member. Functionally, full-length MCL-1 sequesters the proapoptotic proteins Bak and Bax, rendering them inactive. It also delays cell-cycle progression by interacting with CDK1, CHK1 and PCNA. Human MCL-1 is a likely a 350 amino acid (aa) type II transmembrane protein. It contains a large cytoplasmic region (aa 1-327) plus a very short 2 aa C-terminal luminal segment. The cytoplasmic region has multiple domains, including a PEST (Pro/Glu/Ser/Thr)-like segment (aa 104-175), four ubiquitination sites, at least six utilized phosphorylation sites, and three Bcl2-like homology domains (aa 209-223; 252-272; 304-319). MCL-1 is known to form homodimers. There is one splice variant. It is 32-33 kDa in size and contains a 42 aa substitution for aa 230-350. This short form heterodimerizes with full-length MCL-1, rendering it incapable of interacting with Bak and Bax. MCL-1 also undergoes caspase processing. Cleavage after Asp127 generates 17 and 28-30 kDa fragments, while cleavage after Asp 157 generates 21 and 23-25 kDa fragments. These fragments give rise to a proapoptotic environment. Over aa 147-219, human MCL-1 shares 74% aa sequence identity with mouse Mcl-1.