Centaurin-α2 Interacts with β-Tubulin and Stabilizes Microtubules

摘要: Centaurin-α2 is a GTPase-activating protein for ARF (ARFGAP) showing diffuse cytoplasmic localization capable to translocate membrane, where it binds phosphatidylinositols. Taking into account that can localize in cytoplasm and its cytoplasmatic function not well defined, we searched further interactors by yeast two-hybrid assay investigate biological function. We identified interacting protein, β-Tubulin, assay. The interaction, involving the C-terminal region of has been confirmed coimmunoprecipitation experiments. After overexpression HeLa cells extraction soluble (αβ dimers) insoluble (microtubules) fractions Tubulin, observed mainly interacts with polymerized Tubulin fraction, besides colocalizing microtubules (MTs) accordingly. Even following depolimerizing treatments remains associated nocodazole- cold-resistant MTs. found an increase MT stability transfected cells, evaluating as marker level acetylation. In vitro assays using purified tubulin promotes assembly increases microtubule stability. effect overexpression, assessed through detection increased number mitotic bipolar spindles correct centrosomes both dividing consistent role on stabilization. β-Tubulin associates MTs, resistant destabilizing agents, cell. propose new microtubule-associated (MAP) increasing