Fidgetin (FIGN)

Fidgetin (FIGN) is an ATP-dependent microtubule-severing enzyme belonging to the AAA protein superfamily[1][2][4][5][10]. It regulates mitotic spindle architecture and dynamics by severing and depolymerizing microtubules—especially at their minus-ends—and is critical for correct spindle function during cell division[1][5]. Fidgetin localizes primarily to centrosomes during mitosis, where its activity controls centrosome morphology, astral microtubule length, and chromatid-to-pole movement during anaphase[1][4]. Beyond mitosis, Fidgetin modulates cytoskeleton organization in processes such as cell migration and neuronal development, with demonstrated activity in restricting axon growth and impacting the behavior of astrocytes and other cell types[4][7][9]. Mutations in FIGN or its depletion lead to abnormal centrosome morphology, altered microtubule arrays, and are associated with developmental defects in animal models[1][4][9]. No therapeutically approved drugs directly target Fidgetin. However, its essential roles in mitosis, neural development, and cell migration make it a candidate research target for cancer and neurological disease[1][9][10]. Because of its broad role in cytoskeletal regulation, inhibiting Fidgetin could present significant safety challenges, including disruption of cell division and neural development[1][4].

Other names

FidgetinFIGNmicrotubule severing factorATP-dependent microtubule severing protein

Not applicable (no known drugs), theoretical mechanism: inhibitors would reduce microtubule severing activity, stabilizing microtubule arrays; activators would enhance microtubule turnover