Tubulin beta chain isoform (TUBB (or specified by isoform, e.g., TUBB3 for class III))

Tubulin beta chain isoforms are the β subunit of the α/β-tubulin heterodimer that polymerizes to form microtubules, the major cytoskeletal component of eukaryotic cells[1][2][3][5]. Multiple β-tubulin isoforms exist, encoded by distinct genes (e.g., TUBB, TUBB3) and differing in tissue distribution and post-translational modifications[2][6]. β-tubulin plays critical roles in structural support, mitosis, intracellular transport, and specialized functions such as neuronal development[2][4][7]. In disease, altered expression or mutations in β-tubulin isoforms cause tubulinopathies (disorders of brain development) and contribute to cancer pathogenesis and drug resistance[1][2][4]. β-tubulin is the cellular target of several key classes of anticancer drugs, which interfere with microtubule dynamics to exert their effects[1][3][6]. Certain isoforms, like class III β-tubulin (TUBB3), are clinically significant both as biomarkers and mediators of chemotherapy resistance[1][4].

Other names

β-tubulinBeta-tubulin isoformsTubulin beta-3 chain (TUBB3)Class III β-tubulinTUBBTUBB1TUBB2TUBB4BβI-tubulinβIII-tubulinβIVb-tubulin

Microtubule stabilization (e.g., paclitaxel and related drugs bind β-tubulin to block depolymerization, thus arresting mitosis); Microtubule destabilization (e.g., vinca alkaloids bind β-tubulin to promote depolymerization, inhibiting spindle formation in mitosis); Inhibition of microtubule polymerization (e.g., colchicine binds β-tubulin to prevent microtubule assembly)