A functional TOC complex contributes to gravity signal transduction in Arabidopsis

18Citations
Citations of this article
25Readers
Mendeley users who have this article in their library.

Abstract

Although plastid sedimentation has long been recognized as important for a plant's perception of gravity, it was recently shown that plastids play an additional function in gravitropism. The Translocon at the Outer envelope membrane of Chloroplasts (TOC) complex transports nuclear-encoded proteins into plastids, and a receptor of this complex, Toc132, was previously hypothesized to contribute to gravitropism either by directly functioning as a gravity signal transducer or by indirectly mediating the plastid localization of a gravity signal transducer. Here we show that mutations in multiple genes encoding TOC complex components affect gravitropism in a genetically sensitized background and that the cytoplasmic acidic domain of Toc132 is not required for its involvement in this process. Furthermore, mutations in TOC132 enhance the gravitropic defect of a mutant whose amyloplasts lack starch. Finally, we show that the levels of several nuclear-encoded root proteins are altered in toc132 mutants. These data suggest that the TOC complex indirectly mediates gravity signal transduction in Arabidopsis and support the idea that plastids are involved in gravitropism not only through their ability to sediment but also as part of the signal transduction mechanism. © 2014 Strohm, Barrett-Wilt and Masson.

Cite

CITATION STYLE

APA

Strohm, A. K., Barrett-Wilt, G. A., & Masson, P. H. (2014). A functional TOC complex contributes to gravity signal transduction in Arabidopsis. Frontiers in Plant Science, 5(APR). https://doi.org/10.3389/fpls.2014.00148

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free