Regulation of tissue repair in plants

Abstract

Arecent report in PNAS by Asahina et al. (1) addresses the fascinating question of tissue repair in plants. According to recent suggestions, plants and animals might share cellular mechanisms that allow regeneration of tissues after damage (2). However, plants and animals differ greatly in their mode of development and their ability to respond to damage-inducing environmental factors (3). Terrestrial plants cannot move their whole body in response to environmental cues, and, because of their cell walls, they also lack cellular mobility within the plant. This means that plants must regenerate damaged tissue through cellular regeneration at the point of damage. Traditionally, this regeneration was considered to occur by dedifferentiation of existing mature cells followed by cell division to form callus and differentiation to form the cellular constituents of the new tissue, although details of this process have been questioned recently