Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Commissariat à l'Energie Atomique et aux Énergies Alternatives, CNRS, 91198, Gif-sur-Yvette, France.
Physique et physiologie Intégratives de l'Arbre en environnement Fluctuant, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, 63000 Clermont-Ferrand, France.
Proc Natl Acad Sci U S A. 2021 Jan 5;118(1). doi: 10.1073/pnas.1919402118.
Plants spend most of their life oscillating around 1-3 Hz due to the effect of the wind. Therefore, stems and foliage experience repetitive mechanical stresses through these passive movements. However, the mechanism of the cellular perception and transduction of such recurring mechanical signals remains an open question. Multimeric protein complexes forming mechanosensitive (MS) channels embedded in the membrane provide an efficient system to rapidly convert mechanical tension into an electrical signal. So far, studies have mostly focused on nonoscillatory stretching of these channels. Here, we show that the plasma-membrane MS channel MscS-LIKE 10 (MSL10) from the model plant responds to pulsed membrane stretching with rapid activation and relaxation kinetics in the range of 1 s. Under sinusoidal membrane stretching MSL10 presents a greater activity than under static stimulation. We observed this amplification mostly in the range of 0.3-3 Hz. Above these frequencies the channel activity is very close to that under static conditions. With a localization in aerial organs naturally submitted to wind-driven oscillations, our results suggest that the MS channel MSL10, and by extension MS channels sharing similar properties, represents a molecular component allowing the perception of oscillatory mechanical stimulations by plants.
由于风的影响,植物一生中的大部分时间都在 1-3Hz 之间振荡。因此,茎和叶子会通过这些被动运动经历重复的机械应力。然而,细胞感知和转导这种周期性机械信号的机制仍然是一个悬而未决的问题。形成机械敏感(MS)通道的多聚体蛋白复合物嵌入在膜中,提供了一个将机械张力快速转化为电信号的有效系统。到目前为止,这些研究主要集中在这些通道的非振荡拉伸上。在这里,我们表明来自模式植物的质膜 MS 通道 MscS-LIKE 10(MSL10)对脉冲膜拉伸有快速的激活和弛豫动力学反应,在 1s 的范围内。在正弦膜拉伸下,MSL10 的活性比静态刺激时更高。我们观察到这种放大主要在 0.3-3Hz 的范围内。在这些频率以上,通道的活性非常接近静态条件下的活性。由于 MSL10 定位于自然受到风驱动振荡的气生器官,我们的结果表明,MS 通道 MSL10 以及具有类似特性的 MS 通道,代表了允许植物感知振荡机械刺激的分子成分。