Cytokinin functions as an asymmetric and anti-gravitropic signal in lateral roots

0507913 - ÚEB 2020 RIV GB eng J - Journal Article
Waidmann, S. - Ruiz Rosquete, M. - Schöller, M. - Sarkel, E. - Lindner, H. - LaRue, T. - Petřík, Ivan - Dünser, K. - Martopawiro, S. - Sasidharan, R. - Novák, Ondřej - Wabnik, K. - Dinneny, J. R. - Kleine-Vehn, J.
Cytokinin functions as an asymmetric and anti-gravitropic signal in lateral roots.
Nature Communications. Roč. 10, AUG 6 (2019), č. článku 3540. E-ISSN 2041-1723
R&D Projects: GA MŠMT(CZ) LO1204
Institutional support: RVO:61389030
Keywords : SET-POINT ANGLE * AUXIN EFFLUX * CELL-PROLIFERATION
OECD category: Biochemistry and molecular biology
Impact factor: 12.121, year: 2019
Method of publishing: Open access
http://dx.doi.org/10.1038/s41467-019-11483-4

Directional organ growth allows the plant root system to strategically cover its surroundings. Intercellular auxin transport is aligned with the gravity vector in the primary root tips, facilitating downward organ bending at the lower root flank. Here we show that cytokinin signaling functions as a lateral root specific anti-gravitropic component, promoting the radial distribution of the root system. We performed a genome-wide association study and reveal that signal peptide processing of Cytokinin Oxidase 2 (CKX2) affects its enzymatic activity and, thereby, determines the degradation of cytokinins in natural Arabidopsis thaliana accessions. Cytokinin signaling interferes with growth at the upper lateral root flank and thereby prevents downward bending. Our interdisciplinary approach proposes that two phytohormonal cues at opposite organ flanks counterbalance each other’s negative impact on growth, suppressing organ growth towards gravity and allow for radial expansion of the root system.
Permanent Link: http://hdl.handle.net/11104/0298878