Green light stimulates early stem elongation, antagonizing light-mediated growth inhibition
Green light stimulates early stem elongation, antagonizing light-mediated growth inhibition
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DOI：
10.1104/pp.104.038893
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发表时间：
2004-07-01
期刊：
影响因子：
7.4
通讯作者：
Folta, KM
中科院分区：
文献类型：
--
作者：
Folta, KM
在从黑暗到光明的过渡过程中，下胚轴伸长的速率是由通过趋光素、隐色素和光敏色素信号通路感知的光信号的整合决定的。在研究的所有光照条件下，从紫外光到远红光，早期下胚轴生长在几分钟内迅速而有力地抑制，其方式取决于光照的质量和数量。本研究表明，绿光（GL）照射可使黄化拟南芥幼苗的生长速度迅速提高。在持续照射或短的单脉冲光的类似时间过程中检测到gl介导的生长促进。响应的阈值在10（-1）和10(0)μ mol m（-2）之间，在10(2)μ mol m（-2）之前饱和，并服从互易性。遗传分析表明，隐色素或趋光素光感受器不参与反应。主要光敏色素受体影响GL响应的正常幅度和时间，但在恒定的暗红光下生长数小时的幼苗中，GL响应是正常的。因此，光敏色素活化增强，但不是必需的。， GL响应。绿光、红光和蓝光一起生长的幼苗比单独在红光和蓝光下生长的幼苗长。这些数据表明，一种新型的gl激活光传感器可以促进早期茎伸长，从而对抗生长抑制。
During the transition from darkness to light, the rate of hypocotyl elongation is determined from the integration of light signals sensed through the phototropin, cryptochrome, and phytochrome signaling pathways. In all light conditions studied, from UV to far-red, early hypocotyl growth is rapidly and robustly suppressed within minutes of illumination in a manner dependent upon light quality and quantity. In this study, it is shown that green light (GL) irradiation leads to a rapid increase in the growth rate of etiolated Arabidopsis seedlings. GL-mediated growth promotion was detected in response to constant irradiation or a short, single pulse of light with a similar time course. The response has a threshold between 10(-1) and 10(0) mumol m(-2), is saturated before 10(2) mumol m(-2) and obeys reciprocity. Genetic analyses indicate that the cryptochrome or phototropin photoreceptors do not participate in the response. The major phytochrome receptors influence the normal amplitude and timing of the GL response, yet the GL response is normal in seedlings grown for hours under constant dim-red light. Therefore, phytochrome activation enhances, but is not required for., the GL response. Seedlings grown under green, red, and blue light together are longer than those grown under red and blue alone. These data indicate that a novel GL-activated light sensor promotes early stem elongation that antagonizes growth inhibition.