The oncoprotein 18/stathmin family of microtubule destabilizers

The past several years have seen major advances in our understanding of the mechanisms of microtubule destabilization by oncoprotein 1 8/stathmin (Op 1 8/stathmin) and related proteins. New structural information has clearly shown how members of the Op 1 8/stathmin protein family bind tubulin dimers and suggests models for how these proteins stimulate catastrophe, the transition from microtubule growth to shortening. Regulation of Op1 8/stathmin by phosphorylation continues to capture much attention. Studies suggest that phosphorylation occurs in a localized fashion, resulting in decreased microtubule destabilizing activity near chromatin or microtubule polymer. A spatial gradient of inactive Op1 8/stathmin associated with chromatin or microtubules could contribute significantly to mitotic spindle assembly.