The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.
Use at an assay dependent concentration. Detects a band of approximately 26 kDa (predicted molecular weight: 26 kDa).
1/200. for 10 minutes at RT. Staining of formalin-fixed tissues requires boiling tissue sections in 10mM Citrate buffer, pH 6.0 for 10 minutes followed by cooling at RT for 20 minutes.
FunctionPotent inhibitor of cell death. Inhibits activation of caspases (By similarity). Appears to regulate cell death by blocking the voltage-dependent anion channnel (VDAC) by binding to it and preventing the release of the caspase activator, CYC1, from the mitochondrial membrane. Isoform Bcl-X(S) promotes apoptosis.
Tissue specificityBcl-X(S) is expressed at high levels in cells that undergo a high rate of turnover, such as developing lymphocytes. In contrast, Bcl-X(L) is found in tissues containing long-lived postmitotic cells, such as adult brain.
Sequence similaritiesBelongs to the Bcl-2 family.
DomainThe BH4 motif is required for anti-apoptotic activity. The BH1 and BH2 motifs are required for both heterodimerization with other Bcl-2 family members and for repression of cell death.
Post-translational modificationsProteolytically cleaved by caspases during apoptosis. The cleaved protein, lacking the BH4 motif, has pro-apoptotic activity.
Cellular localizationMitochondrion membrane. Nucleus membrane. Mitochondrial membranes and perinuclear envelope.