Biology Department, 208 Mueller Laboratory, Pennsylvania State University, University Park, PA, USA.
FEBS Lett. 2018 Oct;592(20):3429-3437. doi: 10.1002/1873-3468.13249. Epub 2018 Sep 24.
The receptor-like kinase FERONIA (FER) pleiotropically affects plant reproduction, development, and stress tolerance. We recently showed that the FER ligand RALF1 promotes stomatal closure and inhibits stomatal opening in a G-protein-dependent manner. FER responses have been designated as kinase-dependent or kinase-independent, based largely on fer complementation assays employing a kinase-dead FERK565R. Our quantification of FERK565R-GFP transcript and FERK565R-GFP protein in fer complementation lines reveal that, even within individual complementation lines, different levels of FERK565R expression prevail. FERK565R-GFP expression comparable to that of FER in Col-0 plants fail to elicit complementation of either fer rosette phenotypes or RALF1-elicited stomatal movements, whereas overexpression levels of FERK565R-GFP result in complementation. These results suggest possible alternative interpretations of previous conclusions regarding kinase-independent FER signaling.
受体样激酶 FERONIA（FER）广泛影响植物的生殖、发育和抗逆性。我们最近发现，FER 配体 RALF1 以 G 蛋白依赖的方式促进气孔关闭和抑制气孔开放。FER 反应被指定为依赖激酶或不依赖激酶，这主要基于使用激酶失活 FERK565R 的 fer 互补测定。我们对 fer 互补系中 FERK565R-GFP 转录本和 FERK565R-GFP 蛋白的定量分析表明，即使在单个互补系中，FERK565R 的表达水平也存在差异。在 Col-0 植物中，FERK565R-GFP 的表达水平与 FER 相当，但未能引起 fer 莲座叶表型或 RALF1 诱导的气孔运动的互补，而 FERK565R-GFP 的过表达水平则导致互补。这些结果表明，以前关于不依赖激酶的 FER 信号的结论可能存在其他解释。
