Analysis of regulations of root bending in respose to environmental stimuli using wav2 and wav3 mutants

Abstract

To understand how the root growth direction changes in response to environmental stimuli, we characterized an Arabidopsis mutant, wav2 and wav3, whose roots show abnormal wavy growth patterns on inclined agar medium.
The roots of the wav2 mutant show the shorter-pitch wavy growth pattern on inclined agar and bent with larger curvature in gravitropic and phototropic responses than those of the wild-type. The cell-file rotations of the wav2-1 root in the wavy growth pattern were enhanced in both right-handed and left-handed rotation. WAV2 encodes a protein with a transmembrane domain and an α/β-hydrolase domain. Expression analyses showed that WAV2 was expressed strongly in adult plant roots and seedlings, especially in the root tip, the cell elongation zone, and the stele. Our results suggest that WAV2 negatively regulates stimulus-induced root bending through inhibition of root tip rotation.
In addition, we introduce recent studies on the wav3 mutant in this meeting.