Adaptation of roots to low water potentials by changes in cell wall extensibility and cell wall proteins.
It is common for the root/shoot ratio of plants to increase when water availability is limiting. This ratio increases because roots are less sensitive than shoots to growth inhibition by low water potentials. The physiological and molecular mechanisms that assist root growth under drought conditions are reviewed, with a focus on changes in cell walls. Maize seedlings adapt to low water potential by making the walls in the apical part of the root more extensible. In part, this is accomplished by increases in expansin activity and in part by other, more complex changes in the wall. The role of xyloglucan endotransglycosylase, peroxidase and other wall enzymes in root adaptation to low water potential is evaluated and some of the complications in the field of study are listed.
Wu
Y
Y
Department of Biology, 208 Mueller Laboratory, Penn State University, University Park, PA 16802, USA. YXW17@PSU.EDU
Cosgrove
D J
DJ
D000222:Adaptation, Physiological; D002473:Cell Wall / Q000502:physiology*; D016695:Glycosyltransferases / Q000502:physiology; D008565:Membrane Proteins / Q000502:physiology*; D010940:Plant Proteins / Q000502:physiology; D018517:Plant Roots / Q000201:enzymology / Q000502:physiology*; D014867:Water
D008565:Membrane Proteins; D010940:Plant Proteins; C095825:expansin protein, plant; D014867:Water; D016695:Glycosyltransferases; C073693:xyloglucan endotransglycosylase