Photo-Induced Oligomerization of Arabidopsis Thaliana Phototropin 2 LOV1
Photo-Induced Oligomerization of Arabidopsis Thaliana Phototropin 2 LOV1
复制标题
拟南芥趋光素 2 LOV1 的光诱导寡聚化
DOI：
10.1021/jp509448b
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
M. Terazima
中科院分区：
文献类型：
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作者：
Y. Nakasone;Y. Kawaguchi;S-G. Kong;M. Wada;M. Terazima
向光素是植物中的蓝光敏感感光蛋白。向光素由两个发生光化学反应的 LOV（光、氧和电压传感器）域（LOV1 和 LOV2）组成。尽管LOV2结构域的光化学反应已被广泛研究，但LOV1结构域的反应仍未解决。在本研究中，通过瞬态光栅（TG）方法揭示了拟南芥趋光素2 LOV1（phot2LOV1）结构域的反应。 TG 信号显示光激发时扩散系数 (D) 发生显着变化。这种变化对蛋白质浓度和观察时间范围敏感。这些观察结果是通过假设存在反应性和非反应性形式来解释的，并且这些物质的分数依赖于浓度。从动力学的浓度依赖性来看，发现单体形成二聚体；然而，二聚体没有表现出可观察到的反应。在黑暗状态下，两种物质都处于平衡状态，并且在光谱上无法区分。对于具有铰链结构域的LOV1结构域，反应方案与LOV1结构域样品相同，但D变化受到铰链结构域的存在的影响。这一观察表明铰链区在光反应过程中经历构象变化。
Phototropins are blue-light-sensitive photoreceptor proteins in plants. Phototropins consist of two LOV (light, oxygen, and voltage sensor) domains (LOV1 and LOV2) that undergo photochemical reactions. Although the photochemical reaction of the LOV2 domain has been investigated extensively, the reaction of the LOV1 domain remains unresolved. In this study, the reactions of theArabidopsisphototropin 2 LOV1 (phot2LOV1) domain were revealed by the transient grating (TG) method. The TG signal showed a significant diffusion coefficient (D) change upon photoexcitation. This change was sensitive to the protein concentration and the observation time range. These observations were explained by assuming that there are reactive and nonreactive forms, and the fraction of these species is concentration dependent. From the concentration dependence of the dynamics, the monomer was found to form a dimer; however, the dimer does not exhibit an observable reaction. In the dark state, both species were in equilibrium and were not distinguishable spectroscopically. For the LOV1 domain with the hinge domain, the reaction scheme was the same as the LOV1 domain sample, but theDchange was affected by the presence of the hinge region. This observation suggested that the hinge region undergoes a conformational change during the photoreaction.