NF-kB is silenced in the cytoplasm by an inhibitory protein, IkB (1). Synthesis of IkBa is autoregulated (2). IkB proteins are phosphorylated by IkB kinase complex consisting of at least three proteins, IKK1/a, IKK2/b, and IKK3/g (3-6). External stimuli such as tumor necrosis factor or other cytokines initiates a signal transduction cascade that leads to the activation of IkB-kinase complex that specifically phosphorylates IkBa on Serine-32 and Serine-36. Phosphorylation of these sites leads to ubiquitination of IkBa and subsequent degradation by the 26 S proteasome. Degradation of IkBa results in unmasking of the nuclear localization signal of NF-kB dimers, which subsequently translocates to the nucleus and activates target genes (7,8). Six members of IkB family members have been identified (1). One of the first gene induced following NF-kB activation is IkBa.
Suitable for use in ELISA. Other applications not tested.
Optimal dilutions to be determined by the researcher.
Positive Control: TNFa treated Jurkat
Storage and Stability:
May be stored at 4 degrees C for short-term only. For long-term storage and to avoid repeated freezing and thawing, add sterile glycerol (40-50%), aliquot and store at -20 degrees C. Aliquots are stable for at least 3 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.