Anti-Tau, 15-25 Antibody

Anti-Tau, 15-25 Antibody (Previously Covance catalog# MMS-520R)
TAU-13
Catalog# / Size 835201 / 500 µL
Clone
Regulatory Status RUO
Other Names Microtubule-associated protein tau, PHF-tau, paired helical filament-tau, neurofibrillary tangle
protein, microtubule-associated protein tau, isoform 4, G protein beta1/gamma2 subunitinteracting factor 1
Previously Covance Catalog# MMS-520R
Isotype Mouse IgG1, κ
Description Tau proteins are microtubule-associated protein (MAPs) which are abundant in neurons of the
central nervous system, but are also expressed at very low levels in CNS astrocytes and
oligodendrocytes and elsewhere. One of tau's main functions is to modulate the stability of
axonal microtubules. Tau is active primarily in the distal portions of axons providing
microtubule stabilization as well as flexibility. Pathologies and dementias of the nervous
system such as Alzheimer's disease feature tau proteins that have become defective and no
longer stabilize microtubules properly. As a result, tau forms aggregates with specific structural
properties referred to as Paired Helical Filaments (PHFs) that are a characteristic of many
different types of dementias, known as tauopathies. Tau has two primary ways of controlling
microtubule stability: isoforms and phosphorylation. Six tau isoforms exist in human brain
tissue, and they are distinguished by the number of binding domains. Three isoforms have
three binding domains and the remaining three have four binding domains. The binding
domains are located in the carboxy-terminus of the protein and are positively-charged (for
binding to the negatively-charged microtubule). Tau isoforms with four binding domains are
better at stabilizing microtubules than those with three binding domains. Thus, in the human
brain, the tau proteins constitute a family of six isoforms with the range from 352-441 amino
acids. They also differ in either zero, one or two inserts of 29 amino acids at the N-terminal
part (exon 2 and 3), and three or four repeat-binding regions at the C-terminus. So, the longest
isoform in the CNS has four repeats (R1, R2, R3 and R4) and two inserts (441 amino acids
total), while the shortest isoform has three repeats (R1, R3 and R4) and no insert (352 amino
acids total). Tau is also a phosphoprotein with 79 potential Serine (Ser) and Threonine (Thr)
phosphorylation sites on the longest tau isoform. Phosphorylation has been reported on
approximately 30 of these sites in normal tau proteins. Mechanisms that drive tau lesion
formation in the highly prevalent sporadic form of AD are not fully understood, but appear to
involve abnormal post-translational modifications (PTMs) that influence tau function, stability,
and aggregation propensity.