Convergence of light and chloroplast signals for de-etiolation through ABI4–HY5 and COP1

作  者:Xu XM, Chi W, Sun XW, Feng PQ, Guo HL, Li J, Lin RC, Lu CM, Wang HY, Leister D, Zhang LX*
影响因子:
刊物名称:Nature Plants
出版年份:2016
卷:2  期:  页码:16066

论文摘要:

Seedling de-etiolation prepares plants to switch from heterotrophic to photoautotrophic growth, a transition essential for plant survival. This delicate de-etiolation process is precisely controlled by environmental and endogenous signals. Although intracellular plastid-derived retrograde signalling is essential for the de-etiolation process, the molecular nature of these retrograde signals remains elusive1,​2,​3. Here we show that chloroplast and light signals antagonistically fine-tune a suite of developmental and physiological responses associated with de-etiolation through a transcriptional module of ABA INSENSITIVE 4 (ABI4) and ELONGATED HYPOCOTYL 5 (HY5). Moreover, ABI4 and HY5 antagonistically regulate the expression of CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) and the subsequent greening process. In turn, ABI4 and HY5 are targeted for degradation by COP1 in the light and dark, respectively, to ensure a proper interplay of ABI4 and HY5 actions during seedling de-etiolation. Our study provides a new molecular mechanism for understanding how chloroplast signals converge with light signals to optimize early plant development.