Reduction-oxidation poise regulates the sign of phototaxis in Chlamydomonas reinhardtii
Reduction-oxidation poise regulates the sign of phototaxis in Chlamydomonas reinhardtii
复制标题
DOI：
10.1073/pnas.1100592108
复制
发表时间：
2011-07-05
影响因子：
11.1
通讯作者：
Kamiya, Ritsu
中科院分区：
文献类型：
--
作者：
Wakabayashi, Ken-ichi;Misawa, Yuka;Kamiya, Ritsu
在许多光养微生物和植物中，叶绿体改变其相对于入射光的位置以实现最佳光合作用。在能动的绿色藻类的情况下，细胞通过在正趋光性和负趋光性之间切换来改变它们的游动方向，即，游泳朝向或远离光源，这取决于环境和内部条件。然而，我们对决定趋光方向的分子信号知之甚少。使用绿色荧光体莱茵衣藻，我们发现细胞的还原-氧化（氧化还原）平衡起着关键作用：细胞总是表现出积极的趋光性后，与活性氧（ROS）处理，总是表现出负趋光性后，与ROS淬灭剂处理。趋光性信号的氧化还原依赖性转换可能反过来有助于维持细胞的氧化还原稳态。
In many phototrophic microorganisms and plants, chloroplasts change their positions relative to the incident light to achieve optimal photosynthesis. In the case of motile green algae, cells change their swimming direction by switching between positive and negative phototaxis, i.e., swimming toward or away from the light source, depending on environmental and internal conditions. However, little is known about the molecular signals that determine the phototactic direction. Using the green alga Chlamydomonas reinhardtii, we found that cellular reduction-oxidation (redox) poise plays a key role: Cells always exhibited positive phototaxis after treatment with reactive oxygen species (ROS) and always displayed negative phototaxis after treatment with ROS quenchers. The redox-dependent switching of the sign of phototaxis may contribute in turn to the maintenance of cellular redox homeostasis.