Key features and details
- Assay type: Semi-quantitative
- Detection method: Colorimetric
- Platform: Microplate reader
- Sample type: Cell culture extracts, Cell Lysate
Product nameHuman NFkB p50 Transcription Factor Assay Kit
See all NFkB p105 / p50 kits
Sample typeCell culture extracts, Cell Lysate
Species reactivityReacts with: Human
ab133105 Human NFkB p50 Transcription Factor Assay Kit is a non-radioactive, sensitive method for detecting specific transcription factor DNA binding activity in nuclear extracts and whole cell lysates.
A 96-well enzyme-linked immunosorbent assay (ELISA) replaces the cumbersome radioactive electrophoretic mobility shift assay (EMSA). A specific double stranded DNA (dsDNA) sequence containing the NFkB response element is immobilized onto the bottom of wells of a 96-well plate. NFkB contained in a nuclear extract, binds specifically to the NFkB response element. NFkB (p50) is detected by addition of specific primary antibody directed against NFkB (p50). A secondary antibody conjugated to HRP is added to provide a sensitive colorimetric readout at 450 nm. ab133105 detects Human NFkB (p50). It will not cross-react with NFkB (p65).
Storage instructionsPlease refer to protocols.
Components 96 tests 96-Well Plate Cover 1 unit Polysorbate 20 1 vial Transcription Factor Antibody Binding Buffer (10X) 1 x 3ml Transcription Factor Binding Assay Buffer (4X) 1 x 3ml Transcription Factor Developing Solution 1 x 12ml Transcription Factor Goat Anti-Rabbit HRP Conjugate 1 x 100µl Transcription Factor NFkB (Human p50) Positive Control 1 vial Transcription Factor NFkB (Human p50) Primary Antibody 1 vial Transcription Factor NF-kB 96-Well Strip Plate 1 unit Transcription Factor NFkB Competitor dsDNA 1 vial Transcription Factor Reagent A 1 x 120µl Transcription Factor Stop Solution 1 x 12ml Wash Buffer Concentrate (400X) 1 x 5ml
FunctionNF-kappa-B is a pleiotropic transcription factor which is present in almost all cell types and is involved in many biological processed such as inflammation, immunity, differentiation, cell growth, tumorigenesis and apoptosis. NF-kappa-B is a homo- or heterodimeric complex formed by the Rel-like domain-containing proteins RELA/p65, RELB, NFKB1/p105, NFKB1/p50, REL and NFKB2/p52 and the heterodimeric p65-p50 complex appears to be most abundant one. The dimers bind at kappa-B sites in the DNA of their target genes and the individual dimers have distinct preferences for different kappa-B sites that they can bind with distinguishable affinity and specificity. Different dimer combinations act as transcriptional activators or repressors, respectively. NF-kappa-B is controlled by various mechanisms of post-translational modification and subcellular compartmentalization as well as by interactions with other cofactors or corepressors. NF-kappa-B complexes are held in the cytoplasm in an inactive state complexed with members of the NF-kappa-B inhibitor (I-kappa-B) family. In a conventional activation pathway, I-kappa-B is phosphorylated by I-kappa-B kinases (IKKs) in response to different activators, subsequently degraded thus liberating the active NF-kappa-B complex which translocates to the nucleus. NF-kappa-B heterodimeric p65-p50 and RelB-p50 complexes are transcriptional activators. The NF-kappa-B p50-p50 homodimer is a transcriptional repressor, but can act as a transcriptional activator when associated with BCL3. NFKB1 appears to have dual functions such as cytoplasmic retention of attached NF-kappa-B proteins by p105 and generation of p50 by a cotranslational processing. The proteasome-mediated process ensures the production of both p50 and p105 and preserves their independent function, although processing of NFKB1/p105 also appears to occur post-translationally. p50 binds to the kappa-B consensus sequence 5'-GGRNNYYCC-3', located in the enhancer region of genes involved in immune response and acute phase reactions. In a complex with MAP3K8, NFKB1/p105 represses MAP3K8-induced MAPK signaling; active MAP3K8 is released by proteasome-dependent degradation of NFKB1/p105.
Sequence similaritiesContains 7 ANK repeats.
Contains 1 death domain.
Contains 1 RHD (Rel-like) domain.
DomainThe C-terminus of p105 might be involved in cytoplasmic retention, inhibition of DNA-binding, and transcription activation.
Glycine-rich region (GRR) appears to be a critical element in the generation of p50.
modificationsWhile translation occurs, the particular unfolded structure after the GRR repeat promotes the generation of p50 making it an acceptable substrate for the proteasome. This process is known as cotranslational processing. The processed form is active and the unprocessed form acts as an inhibitor (I kappa B-like), being able to form cytosolic complexes with NF-kappa B, trapping it in the cytoplasm. Complete folding of the region downstream of the GRR repeat precludes processing.
Phosphorylation at 'Ser-903' and 'Ser-907' primes p105 for proteolytic processing in response to TNF-alpha stimulation. Phosphorylation at 'Ser-927' and 'Ser-932' are required for BTRC/BTRCP-mediated proteolysis.
Polyubiquitination seems to allow p105 processing.
S-nitrosylation of Cys-61 affects DNA binding.
Cellular localizationNucleus. Cytoplasm. Nuclear, but also found in the cytoplasm in an inactive form complexed to an inhibitor.
- Information by UniProt
- DNA binding factor KBF1
- DNA binding factor KBF1 EBP1
sELISA pair antibody
ab133105 has not yet been referenced specifically in any publications.