<i>ARABIDOPSIS THALIANA HOMEOBOX GENE 1</i> controls plant architecture by locally restricting environmental responses
Mahwish Ejaz, Stefano Bencivenga, Rafael Tavares, Max Bush, Robert Sablowski
Abstract
Significance A major issue in plant biology is how plants are shaped by the interaction between internal genetic programs—for example, those that form boundaries between leaves and the stem—and environmental signals such as light quality, which induces stem elongation in shade conditions. In many plant species, stem growth is suppressed during the vegetative phase, resulting in a compact whorl of leaves called a rosette. We show that the rosette habit of Arabidopsis is conferred by a gene involved in organ boundary formation, together with gibberellin hormone signaling, both of which antagonize genes that mediate organ growth in response to light. In this way, a common type of plant architecture results from localized inhibition of environmentally responsive growth.