HY5 suppresses, rather than promotes, abscisic acid-mediated inhibition of postgermination seedling development

Abstract

Seed germination and postgermination seedling establishment are crucial early developmental events in angiosperms. Although the demarcations between these two successive events appear to be elusive, they have been defined as distinct developmental processes and identified to involve separate regulatory mechanisms at the molecular level. Seed germination is marked by the protrusion of embryonic root out of the seed coat. Postgermination seedling establishment denotes the developmental window after germination that involves the opening, greening, and expansion of cotyledons or foliar leaves, marking the switch to autotrophic development