Mouse Monoclonal Antibody to MAP-τ, aka tau Protein
Cat# MCA-5B10

      MAP-τ is a low molecular weight member of the microtubule associated protein or MAP family. Several serious human diseases are associated with accumulations of MAP-τ, usually referred to as tau protein, most notably the neurofibrillary tangles of Alzheimer’s disease. Accumulations of tau in neurons are also characteristic of chronic traumatic encephalopathy, Pick’s disease and several other neurodegenerative diseases. Together these disorders are known as “tauopathies”. The single mammalian tau gene produces at least 9 different proteins by alternate transcription. In the central nervous system 6 isoforms ranging from 48-67kDa by SDS-PAGE predominate, though larger isotypes are seen mostly in the peripheral nervous system. The tau molecules are very heavily charged and run on SDS-PAGE much more slowly than predicted from their real molecular size. For example the smallest human tau isotype runs at 48kDA on SDS-PAGE but the real molecular weight is 32kDa. Tau proteins are substrates for ser/thr phosphorylation and other post-translational modifications.
      The MCA-5B10 antibody was raised against a recombinant form of one of the lower molecular weight human tau isoform, specifically the human 441 amino acid htau40 form described by Goedert et al. The epitope for this antibody is located in the peptide HVPGGGNKKIETHKLTFREN, amino acids 362-381 of the sequence in NP_005901.2. This corresponds to the C-terminus of the ultimate microtubule binding peptide repeat and some following sequence, see the exact sequence in Tau-Epitopes.pdf. This sequence is expressed in all known human tau isotypes and is totally conserved in all mammals and other higher vertebrates. As a result the antibody will have wide applicability. The antibody works well for western blotting and for IF, ICC and IHC (see data under “Additional Info” tab). We have another mouse monoclonal antibody raised against the same form of human tau, MCA-2E9, which binds the peptide KDRVQSKIGSLDNITHVPGG, amino acids 347-366, immediately preceding the epitope for MCA-5B10. This is within the ultimate microtubule binding peptide. Both antibodies recognize the unphosphorylated forms of tau. We have not to date examined the effect of tau phosphorylation on binding of either antibody. MCA-5B10 works well on western blots IF, ICC and IHC of human brain tissue. Mouse select image at left for larger view.