CONSTITUTIVE PHOTOMORPHOGENIC 1 promotes seed germination by destabilizing RGA-LIKE 2 in Arabidopsis.
CONSTITUTIVE PHOTOMORPHOGENIC 1 promotes seed germination by destabilizing RGA-LIKE 2 in Arabidopsis.
复制标题
DOI：
10.1093/plphys/kiac060
复制
发表时间：
2022-06-27
期刊：
影响因子：
7.4
通讯作者：
中科院分区：
文献类型：
--
作者：
在有利的湿度、温度和光照条件下，赤霉素（GA）的生物合成被诱导并触发种子萌发。GA促进种子萌发的主要机制是通过促进DELLA蛋白RGA-LIKE 2 （RGL2）的降解，RGA-LIKE 2是拟南芥种子萌发的主要抑制因子。对组成型光形态发生1 （cop1）突变体和cop1- ox /cop1-4互补系对GA和多效唑（paclobutrazol， PAC）的种子萌发表型分析表明，cop1在种子萌发中起积极作用，并与GA信号传导有关。COP1 -4突变体种子对PAC敏感，但COP1过表达构建体的转化使其对PAC不敏感，其表型与rgl2突变体（rgl2- sk54）种子相似。此外，COP1 -4 RGL2 - sk54双突变体表现出与RGL2 - sk54相似的pac不敏感萌发表型，表明COP1是RGL2的上游负调控因子。COP1直接与RGL2相互作用，在体内，这种相互作用被phya - 105.1的SUPPRESSOR强烈增强。COP1直接泛素化RGL2，促进其降解。此外，GA稳定了COP1，导致RGL2失稳。通过发现这个COP1 - rgl2调控模块，我们揭示了COP1正向调控种子萌发和控制萌发促进基因表达的机制。一个光形态发生的主要调控因子通过直接泛素化和促进种子萌发关键抑制因子的降解来正向调节拟南芥种子的萌发。
Under favorable moisture, temperature, and light conditions, gibberellin (GA) biosynthesis is induced and triggers seed germination. A major mechanism by which GA promotes seed germination is by promoting the degradation of the DELLA protein RGA-LIKE 2 (RGL2), a major repressor of germination in Arabidopsis (Arabidopsis thaliana) seeds. Analysis of seed germination phenotypes of constitutive photomorphogenic 1 (cop1) mutants and complemented COP1-OX/cop1-4 lines in response to GA and paclobutrazol (PAC) suggested a positive role for COP1 in seed germination and a relation with GA signaling. cop1-4 mutant seeds showed PAC hypersensitivity, but transformation with a COP1 overexpression construct rendered them PAC insensitive, with a phenotype similar to that of rgl2 mutant (rgl2-SK54) seeds. Furthermore, cop1-4 rgl2-SK54 double mutants showed a PAC-insensitive germination phenotype like that of rgl2-SK54, identifying COP1 as an upstream negative regulator of RGL2. COP1 interacted directly with RGL2, and in vivo this interaction was strongly enhanced by SUPPRESSOR OF PHYA-105 1. COP1 directly ubiquitinated RGL2 to promote its degradation. Moreover, GA stabilized COP1 with consequent RGL2 destabilization. By uncovering this COP1–RGL2 regulatory module, we reveal a mechanism whereby COP1 positively regulates seed germination and controls the expression of germination-promoting genes. A master regulator of photomorphogenesis positively regulates germination in Arabidopsis seeds by directly ubiquitinating and promoting the degradation of a key repressor of seed germination.
登录
查看更多内容
影响因子：
3.7
作者：
Belda-Palazón B;Ruiz L;Martí E;Tárraga S;Tiburcio AF;Culiáñez F;Farràs R;Carrasco P;Ferrando A
通讯作者：
Ferrando A
影响因子：
11.6
作者：
Ariizumi, Tohru;Steber, Camille M.
通讯作者：
Steber, Camille M.
影响因子：
10.5
作者：
Lee, SC;Cheng, H;Peng, JR
通讯作者：
Peng, JR
影响因子：
7.2
作者：
Gabriele, Stefano;Rizza, Annalisa;Vittorioso, Paola
通讯作者：
Vittorioso, Paola
影响因子：
7.2
作者：
Clough, SJ;Bent, AF
通讯作者：
Bent, AF