Channelrhodopsin colour tuning

视紫红质（ChRs）是绿色藻类的直接光门控离子通道。在神经科学中，ChR用于简单地通过光来兴奋神经元组织或活动物中的选定细胞（Optogenefics）。这种方法为脑内特定细胞的特异性激活和神经元疾病的研究开辟了广阔的前景。最近，我们在COS细胞中成功表达了ChR，并对ChR的光循环进行了详细的分析，结果表明，群体团藻的ChR Ⅰ与衣原体ChR Ⅱ的吸收峰（λ max- 465 nm）相比，有70 nm的rcd位移（535 nm）。在我们申请的项目中，我们的目标是设计新的ChRs，其最大吸收范围覆盖400至600 nm的整个可见光范围。该设计将基于理论计算和光谱研究，主要是团藻-ChR 1，但也对Chlamydium ChR 2。将使用电生理学和光谱学研究新蛋白质的功能。最后，新的蛋白质将在海马细胞和动物模型系统中进行测试。

Channclrhodopsins (ChRs) are directly light-gated ion channels of green algae. In the neurosciences ChRs are used for excitafion of selected cells in neuronal tissues or living animals simply by light (Optogenefics). Such method opens wide perspecfives for specific acfivation of defined cells in the brain and to study neuronal disorders. Recently wc achieved to fiincfionally express ChR in COScells and to analyse the photocycle in detail ChRI ofthe colonial alga Volvox carteri showed an absorption 70 nm rcd shifted (535 nm) compared to that of Chlamydomonas ChR2 (Xmax- 465 nm). In the project we arc applying for we aim to design new ChRs with absorpfion maxima covering the whole visible range from 400 to 600 nm. The design will be based on theoretical calculafions and spectroscopic studies primarily on Volvox-ChRl but also on Chlamdomonas ChR2. Funcfionality of the new proteins will be studied using electrophysiology and spectroscopy. Finally, the new proteins will be tested in hippocampal cells and animal model systems.