Tau is the principal microtubule-associated protein located in axons in the nervous system where it participates in events including the elongation, stabilisation and bundling of microtubules. The tau family consists of six isoforms identified by the insertion of three or four partial repeats of 30-31 amino acids in the C-terminal region. Subcellular fractionation studies have revealed tau to be associated with the membrane fraction, as well as with the cytoskeletal fraction and there is some evidence that the N-terminal domain of tau may be responsible for membrane binding as well as interaction with other cellular components. Tau extracted from human fetal and neonatal brains is moderately phosphorylated with 5-9 phosphorylated serine/threonine residues per molecule. Normal adult human brain tau shows a marked reduction in phosphorylation, but in certain neurodegenerative diseases (tauopathies) tau becomes hyperphosphorylated (6-15 phosphates per tau molecule have been identified) and associates to form filamentous aggregates. In Alzheimer’s disease (AD) hyperphosphorylated tau polymerises to form a mixture of paired helical filaments (PHF) and straight filaments which accumulate and contribute to the formation of neurofibrillary tangles - one of the characteristic features of AD. It was reported in 1998 that tau could be tyrosine phosphorylated when co-transfected with the src-family protein tyrosine kinase fyn. In 2004 the same group, using phospho-specific antibodies, reported that fyn phosphorylated Tyr18 of brain tau at an early developmental stage in mice, but that tyrosine phosphorylated tau was undetectable in adult mice. However, they also showed that PHF preparations were reactive to the tau-pTyr18-specific antibodies, implicating a role for fyn – and possibly other tyrosine kinases - in the neurodegenerative process.
- For Immunohistochemistry, Western Blot
Recognizes human microtubule-associated protein tau.
Type: Primary
Antigen: MAPT
Clonality: Polyclonal
Clone:
Conjugation:
Epitope:
Host: Rabbit
Isotype:
Reactivity: Human
