Nature Cell Biology3, 723 - 729 (2001)
Published online: 12 July 2001; | doi:10.1038/35087035
mDia mediates Rho-regulated formation and orientation of stable microtubules
Alexander F. Palazzo1, Tiffani A. Cook1, Arthur S. Alberts2
& Gregg G. Gundersen1
1
Department of Anatomy & Cell Biology, Columbia University, New York 10032, USA
2
Van Andel Institute, Grand Rapids, Michigan 49503, USA
Correspondence should be addressed to Gregg G. Gundersen ggg1@columbia.edu
Rho-GTPase stabilizes microtubules that are oriented towards the leading edge in serum-starved 3T3 fibroblasts through an unknown mechanism. We used a Rho-effector domain screen to identify mDia as a downstream Rho effector involved in microtubule stabilization. Constitutively active mDia or activation of endogenous mDia with the mDia-autoinhibitory domain stimulated the formation of stable microtubules that were capped and oriented towards the wound edge. mDia co-localized with stable microtubules when overexpressed and associated with microtubules in vitro. Rho kinase was not necessary for the formation of stable microtubules. Our results show that mDia is sufficient to generate and orient stable microtubules, and indicate that Dia-related formins are part of a conserved pathway that regulates the dynamics of microtubule ends.