Beta-tubulin subunit of microtubules (β-tubulin)

Beta-tubulin is a highly conserved globular protein that forms heterodimers with alpha-tubulin. These dimers are the building blocks for microtubules—dynamic cylindrical polymers that are essential components of the eukaryotic cytoskeleton. Microtubules provide structural support, serve as tracks for intracellular transport, and play critical roles in chromosome segregation during cell division. The dynamic behavior of microtubules depends on GTP binding and hydrolysis by the beta subunit; this property underlies their rapid assembly/disassembly cycles crucial for cellular functions such as mitosis. Multiple genes encode different β-tubulin isotypes with tissue-specific expression patterns. Some isotypes are overexpressed in cancers and contribute to chemotherapy resistance. Drugs targeting β-tubulin disrupt microtubule dynamics—either stabilizing them against depolymerization or promoting disassembly—which can halt proliferation especially in rapidly dividing tumor cells but also cause side effects due to impacts on normal tissues. Alterations in β-tubulin function have been implicated not only in cancer but also neurodegenerative diseases and congenital disorders known as tubulinopathies.[1][2][3][5]

Other names

Tubulin beta chainβ-tubulinTUBB (gene family abbreviation)Microtubule beta subunit

Inhibition of microtubule polymerization or depolymerization, leading to cell cycle arrest and apoptosis in rapidly dividing cells[5][6] - Stabilization of microtubules, preventing their disassembly and thus blocking mitosis (e.g., paclitaxel)[6]