Abstract
We have elucidated that the mechanical properties (extensibility, φ; yield threshold tension, y) of the glycerinated cell wall preparations from cowpea hypocotyls (GHCs) were shifted in a pH-dependent manner, and the y was regulated by yieldin. On the other hand, wall creep was proposed to be promoted by expansins under acidic condition. To examine interrelationships of these proteins we adopted Arabidopsis thaliana, extensively studied on its genetic characteristics as a model plant. Here, we tried to examine physiological mechanical wall properties in Arabidopsis with a custom-made extensometer. In the glycerinated wall preparations from Arabidopsis hypocotyls, the pH-dependent shifts of φ and y were observed as in cowpea GHCs. The Arabidopsis system seems to provide a new tool to investigate growth regulation by a combination of physiological and genetic techniques.
