Tau is a microtubule-associated phosphoprotein (MAP), localized in neuronal axons. It promotes tubulin polymerization and stabilizes microtubules. Tau proteins constitute a family of six isoforms, which ranging from 352 to 441 amino acids. The tau variants differ from each other by the presence of either three or four repeat-regions in the carboxy-terminal part of the molecule and the absence or presence of one or two inserts in the amino-terminal portion.
Tau is hyperphosphorylated by ERK, GSK-3, TPKII, and CDK5. At least thirty phosphorylation sites have been described, including Thr39, Ser46, Thr50, Thr69, Thr153, Thr175, Thr181, Ser198, Ser199, Ser202, Thr205, Ser208, Ser210, Thr212, Ser214, Thr217, Thr231, Ser235, Ser237, Ser241, Ser262, Ser285, Ser305, Ser324, Ser352, Ser356, Ser396, Ser400, Thr403, Ser404, Ser409, Ser412, Ser413, Ser416, and Ser422. Specifically, TPKII phosphorylates serines 202 and 404. GSK-3β transfection phosphorylates serines 199, 202, 235, 396, 404, and 413, and threonines 205 and 231. These sites are among the major abnormal phosphorylation sites of tau. Phosphorylation on these sites reduces the ability of a given tau species to promote microtubule self-assembly. Hyperphosphorylated tau is the major protein of the paired helical filaments (PHFs), which make up the pathological neurofibrillary tangles of Alzheimer’s disease (AD). The PHFs are also found in the lesions of other central nervous system disorders. GenScript Rabbit Anti-Tau (Phospho-Ser422) Polyclonal Antibody is developed in rabbit using a synthetic phospho-peptide (KLH-coupled) corresponding to residues surrounding phospho-serine 422 of human tau.
Synthetic phospho-peptide (KLH-coupled) corresponding to residues surrounding phospho-serine 422 of human tau
Affinity-chromatography using phosphopeptide and cross-adsorbed with the corresponding non-phosphopeptide
Reconstitute the lyophilized powder with deionized water (or equivalent) to an final concentration of 0.5 mg/ml.
GenScript Rabbit Anti-Tau (Phospho-Ser422) Polyclonal Antibody detects human tau only when phosphorylated at serine 422. It has not yet been tested with other species.
The antibody is stable in lyophilized form if stored at -20°C or below. The reconstituted antibody can be stored for 2-3 weeks at 2-8°C. For long term storage, aliquot and store at -20°C or below. Avoid repeated freezing and thawing cycles.
Working concentrations for specific applications should be determined by the investigator. The appropriate concentrations may be affected by secondary antibody affinity, antigen concentration, the sensitivity of the method of detection, temperature, the length of the incubations, and other factors. The suitability of this antibody for applications other than those listed below has not been determined. The following concentration ranges are recommended starting points for this product. ELISA: 0.05-0.2 µg/ml Western blot: 0.5-2 µg/ml Other applications: user-optimized