G-protein complex mutants are hypersensitive to abscisic acid regulation of germination and postgermination development (Retracted article. See vol. 181, pg. 1393, 2019)
G-protein complex mutants are hypersensitive to abscisic acid regulation of germination and postgermination development (Retracted article. See vol. 181, pg. 1393, 2019)
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DOI：
10.1104/pp.106.079038
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发表时间：
2006-05-01
期刊：
影响因子：
7.4
通讯作者：
Assmann, SM
中科院分区：
文献类型：
--
作者：
Pandey, S;Chen, JG;Assmann, SM
脱落酸（阿坝）在植物生长发育过程中起着重要的生理调节作用。种子萌发、幼苗早期发育、气孔保卫细胞功能以及对逆境的适应是阿坝调控的关键过程。最近的证据表明，种子和保卫细胞的信号转导过程涉及异源三聚体G蛋白。为了评估拟南芥（Arabidopsis thaliana）G α亚基（GPA1），G β亚基（AGB1）和候选G蛋白偶联受体（GCR1）在萌发和早期幼苗发育过程中阿坝信号转导中的新作用，我们利用了缺乏这些成分中的一个或多个的敲除突变体。我们的数据表明，GPA1，AGB1，和GCR1各自负调节阿坝信号在种子萌发和早期幼苗发育。缺乏AGB1的植物比缺乏GPA1的植物具有更大的阿坝超敏性，这表明AGB1是阿坝信号传导的主要调节器，并且GPA1影响AGB1执行的功效。GCR 1在萌发和早期幼苗发育过程中作为阿坝信号通路的GPA 1和AGB 1的上游：gcr 1 gpa 1双突变体表现出gpa 1表型，agb 1 gcr 1和agb 1 gcr 1 gpa 1突变体表现出agb 1表型。相反的情况下，在保卫细胞，其中GCR1和GPA 1有相反的影响阿坝信号在气孔开放，GCR1的行为与GPA 1和AGB1在阿坝信号在萌发和早期幼苗发育。因此，细胞和组织特异性的功能相互作用，响应于一个给定的信号，如阿坝可能会决定不同的途径调节的G蛋白复合物的个别成员。
Abscisic acid (ABA) plays regulatory roles in a host of physiological processes throughout plant growth and development. Seed germination, early seedling development, stomatal guard cell functions, and acclimation to adverse environmental conditions are key processes regulated by ABA. Recent evidence suggests that signaling processes in both seeds and guard cells involve heterotrimeric G proteins. To assess new roles for the Arabidopsis (Arabidopsis thaliana) G alpha subunit (GPA1), the G beta subunit (AGB1), and the candidate G-protein-coupled receptor (GCR1) in ABA signaling during germination and early seedling development, we utilized knockout mutants lacking one or more of these components. Our data show that GPA1, AGB1, and GCR1 each negatively regulates ABA signaling in seed germination and early seedling development. Plants lacking AGB1 have greater ABA hypersensitivity than plants lacking GPA1, suggesting that AGB1 is the predominant regulator of ABA signaling and that GPA1 affects the efficacy of AGB1 execution. GCR1 acts upstream of GPA1 and AGB1 for ABA signaling pathways during germination and early seedling development: gcr1 gpa1 double mutants exhibit a gpa1 phenotype and agb1 gcr1 and agb1 gcr1 gpa1 mutants exhibit an agb1 phenotype. Contrary to the scenario in guard cells, where GCR1 and GPA1 have opposite effects on ABA signaling during stomatal opening, GCR1 acts in concert with GPA1 and AGB1 in ABA signaling during germination and early seedling development. Thus, cell- and tissue-specific functional interaction in response to a given signal such as ABA may determine the distinct pathways regulated by the individual members of the G-protein complex.