Phototropins are blue-light receptors controlling a range of responses that serve to optimize the photosynthetic efficiency of plants. These include phototropism, light-induced stomatal opening, and chloroplast movements in response to changes in light intensity. Since the isolation of the Arabidopsis PHOT1 gene in 1997, phototropins have been identified in ferns and mosses where their physiological functions appear to be conserved. Arabidopsis contains two phototropins, phot1 and phot2, that exhibit overlapping functions in addition to having unique physiological roles. Phototropins are light-activated serine/threonine protein kinases. Light sensing by the phototropins is mediated by a repeated motif at the N-terminal region of the protein known as the LOV domain. Photoexcitation of the LOV domain results in receptor autophosphorylation and an initiation of phototropin signaling. Here we summarize the photochemical and biochemical events underlying phototropin activation in addition to the current knowledge of the molecular mechanisms associated with photoreceptor signaling.

中文翻译：

---

向光素蓝光受体

向光素是控制一系列反应的蓝光受体，用于优化植物的光合作用效率。这些包括向光性、光诱导的气孔开放和响应光强度变化的叶绿体运动。自 1997 年分离出拟南芥 PHOT1 基因以来，已在蕨类植物和苔藓植物中发现了向光素，它们的生理功能似乎是保守的。拟南芥含有两种向光素，phot1 和 phot2，除了具有独特的生理作用外，它们还表现出重叠的功能。向光素是光激活的丝氨酸/苏氨酸蛋白激酶。光敏素的光感应是由蛋白质 N 末端区域的重复基序介导的，称为 LOV 结构域。LOV 结构域的光激发导致受体自磷酸化和向光素信号传导的启动。在这里，除了与光感受器信号传导相关的分子机制的当前知识外，我们还总结了向光素激活的光化学和生化事件。