The 2G10-TB3 antibody reacts with beta-tubulin III, an ~50 – 55 kDa structural protein that is a constituent of tubulin. Tubulin is the major component of microtubules within the cytoskeleton and is assembled from heterodimers of alpha- and beta-tubulin subunits. The beta III isoform of tubulin, also known as neuron-specific class III beta-tubulin, is expressed primarily in neurons and is widely used as a marker to distinguish neurons from other cell types. Beta-tubulin III contributes to microtubule formation in neuronal cell bodies and axons, a function involving GTP binding, and plays roles in axonal transport, neuronal cell proliferation, and differentiation. It is highly expressed in several types of cancer and is a predictive and prognostic marker for various tumors, for example, being found in neoplastic but not in normal glial cells. The 2G10-TB3 antibody is expected to recognize all mammalian homologs of beta-tubulin III and the epitope has reportedly been mapped to the extreme C-terminal amino acids, EAQGPK.