Liewald Jana F, Brauner Martin, Stephens Greg J, Bouhours Magali, Schultheis Christian, Zhen Mei, Gottschalk Alexander
Institute of Biochemistry, Department of Biochemistry, Chemistry and Pharmacy, Goethe University Frankfurt, Biocenter N220, Frankfurt, Germany.
Nat Methods. 2008 Oct;5(10):895-902. doi: 10.1038/nmeth.1252. Epub 2008 Sep 14.
We introduce optogenetic investigation of neurotransmission (OptIoN) for time-resolved and quantitative assessment of synaptic function via behavioral and electrophysiological analyses. We photo-triggered release of acetylcholine or gamma-aminobutyric acid at Caenorhabditis elegans neuromuscular junctions using targeted expression of Chlamydomonas reinhardtii Channelrhodopsin-2. In intact Channelrhodopsin-2 transgenic worms, photostimulation instantly induced body elongation (for gamma-aminobutyric acid) or contraction (for acetylcholine), which we analyzed acutely, or during sustained activation with automated image analysis, to assess synaptic efficacy. In dissected worms, photostimulation evoked neurotransmitter-specific postsynaptic currents that could be triggered repeatedly and at various frequencies. Light-evoked behaviors and postsynaptic currents were significantly (P <or= 0.05) altered in mutants with pre- or postsynaptic defects, although the behavioral phenotypes did not unambiguously report on synaptic function in all cases tested. OptIoN facilitates the analysis of neurotransmission with high temporal precision, in a neurotransmitter-selective manner, possibly allowing future investigation of synaptic plasticity in C. elegans.
我们引入了神经传递的光遗传学研究（OptIoN），通过行为和电生理分析对突触功能进行时间分辨和定量评估。我们利用莱茵衣藻视紫红质-2的靶向表达，在秀丽隐杆线虫神经肌肉接头处光触发乙酰胆碱或γ-氨基丁酸的释放。在完整的视紫红质-2转基因蠕虫中，光刺激立即诱导身体伸长（对于γ-氨基丁酸）或收缩（对于乙酰胆碱），我们对其进行急性分析，或在持续激活期间通过自动图像分析来评估突触效能。在解剖的蠕虫中，光刺激诱发了神经递质特异性的突触后电流，这些电流可以在不同频率下反复触发。在具有突触前或突触后缺陷的突变体中，光诱发的行为和突触后电流发生了显著变化（P≤0.05），尽管在所有测试案例中，行为表型并未明确报告突触功能。OptIoN以神经递质选择性的方式，促进了对神经传递的高时间精度分析，可能有助于未来对秀丽隐杆线虫突触可塑性的研究。
