RT Journal Article
SR Electronic
T1 Root growth responses to mechanical impedance are regulated by a network of ROS, ethylene and auxin signalling in Arabidopsis
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.09.01.277707
DO 10.1101/2020.09.01.277707
A1 Amy G.R. Jacobsen
A1 Jian Xu
A1 Jennifer F. Topping
A1 Keith Lindsey
YR 2020
UL http://biorxiv.org/content/early/2020/09/02/2020.09.01.277707.abstract
AB The growth and development of root systems, essential for plant performance, is influenced by mechanical properties of the substrate in which the plants grow. Mechanical impedance, such as by compacted soil, can reduce root elongation and limit crop productivity.To understand better the mechanisms involved in plant root responses to mechanical impedance stress, we investigated changes in the root transcriptome and hormone signalling responses of Arabidopsis to artificial root barrier systems in vitro.We demonstrate that upon encountering a barrier, reduced Arabidopsis root growth and the characteristic ‘step-like’ growth pattern is due to a reduction in cell elongation associated with changes in signalling gene expression. Data from RNA-sequencing combined with reporter line and mutant studies identified essential roles for reactive oxygen species, ethylene and auxin signalling during the barrier response.We propose a model in which early responses to mechanical impedance include reactive oxygen signalling that is followed by integrated auxin and ethylene responses to mediate root growth changes. Inhibition of ethylene responses allows improved growth in response to root impedance, a result that may inform future crop breeding programmes.Competing Interest StatementThe authors have declared no competing interest.