Please use this identifier to cite or link to this item: https://doi.org/10.1073/pnas.1118651109
Title: Structural basis for basal activity and autoactivation of abscisic acid (ABA) signaling SnRK2 kinases
Authors: Ng, L.-M.
Soon, F.-F.
Zhou, X.E.
West, G.M.
Kovach, A.
Suino-Powell, K.M.
Chalmers, M.J.
Li, J. 
Yong, E.-L. 
Zhu, J.-K.
Griffin, P.R.
Melcher, K.
Xu, H.E.
Issue Date: 27-Dec-2011
Citation: Ng, L.-M., Soon, F.-F., Zhou, X.E., West, G.M., Kovach, A., Suino-Powell, K.M., Chalmers, M.J., Li, J., Yong, E.-L., Zhu, J.-K., Griffin, P.R., Melcher, K., Xu, H.E. (2011-12-27). Structural basis for basal activity and autoactivation of abscisic acid (ABA) signaling SnRK2 kinases. Proceedings of the National Academy of Sciences of the United States of America 108 (52) : 21259-21264. ScholarBank@NUS Repository. https://doi.org/10.1073/pnas.1118651109
Abstract: Abscisic acid (ABA) is an essential hormone that controls plant growth, development, and responses to abiotic stresses. Central for ABA signaling is the ABA-mediated autoactivation of three monomeric Snf1-related kinases (SnRK2.2, -2.3, and -2.6). In the absence of ABA, SnRK2s are kept in an inactive state by forming physical complexes with type 2C protein phosphatases (PP2Cs). Upon relief of this inhibition, SnRK2 kinases can autoactivate through unknown mechanisms. Here, we report the crystal structures of full-length Arabidopsis thaliana SnRK2.3 and SnRK2.6 at 1.9- and 2.3-Å resolution, respectively. The structures, in combination with biochemical studies, reveal a two-step mechanism of intramolecular kinase activation that resembles the intermolecular activation of cyclin-dependent kinases. First, release of inhibition by PP2C allows the SnRK2s to become partially active because of an intramolecular stabilization of the catalytic domain by a conserved helix in the kinase regulatory domain. This stabilization enables SnRK2s to gain full activity by activation loop autophosphorylation. Autophosphorylation is more efficient in SnRK2.6, which has higher stability than SnRK2.3 and has well-structured activation loop phosphate acceptor sites that are positioned next to the catalytic site. Together, these data provide a structural framework that links ABA-mediated release of PP2C inhibition to activation of SnRK2 kinases.
Source Title: Proceedings of the National Academy of Sciences of the United States of America
URI: http://scholarbank.nus.edu.sg/handle/10635/127006
ISSN: 00278424
DOI: 10.1073/pnas.1118651109
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

68
checked on Nov 13, 2018

WEB OF SCIENCETM
Citations

67
checked on Nov 13, 2018

Page view(s)

21
checked on Oct 12, 2018

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.