Study on the neural mechanisms fix insect photoperiodism: from the photoreceptor to the effecter

本研究旨在阐明豆蝽Riptortus pedestris和丽蝇Protophormia terraenoestris的光感受器、光周期钟和光周期效应系统。在pedestris的研究中，我们观察了复眼中部的小眼向大脑的投射，并确定了两种终止于大脑后复合体的神经元，其中包括光周期性的内分泌效应器--侧咽体。这些神经元的选择性消融表明，在侧部的神经元是重要的光周期。此外，外侧部的两组神经元都参与了光周期活动。在P. terraenoptera中，我们描述了脑中生物钟神经元的形态，并发现生物钟神经元与侧部神经元之间的突触联系;后者已被证明在这种光周期中起重要作用。 ...更多信息 种也。从消融实验的结果，我们建议参与的昼夜节律钟神经元的光周期。这是首次在神经元水平上发现昼夜节律钟神经元参与光周期现象。pedestris中，我们确定了四个生物钟基因，period，cycle，vrille和cryptochrome 2。然而，这些基因的表达没有明显的每日波动，光周期条件之间也没有差异。在陆生毕赤酵母中，period和timeless两个生物钟基因的表达呈现相似的日波动，但在光周期条件下没有光周期差异。基于在其他昆虫中获得的实验结果，已经提出生物钟基因的表达模式在光周期性中起重要作用。然而，这在这两个物种中是不合理的，我们必须研究光周期性分子机制的其他机制。少

The present study aims to clarify the photoreceptor, photoperiodic clock and effecter system for photoperiodism in the bean bug Riptortus pedestris and the blow fly Protophormia terraenovae.In R. pedestris, we examined the projection from the ommatidia in the central part of the compound eye, which had been shown to be important in photoperiodic photoreception, to the brain, and then identified two kinds of neurons terminating in the retrocerebral complex including corpus allatum, the endocrine effecter of the photoperiodism. Selective ablation of these neurons showed that neurons in the pars lateralis are important in the photoperiodism. Moreover, both of the two groups of neurons in the pars lateralis are involved in the photoperiodism. In P. terraenovae, we described the morphology of circadian clock neurons in the brain, and found synaptic connection between circadian clock neurons and the pars lateralis neurons; the latter have been shown to be important in photoperiodism of this … More species also. From the results of ablation experiments, we suggest the involvement of the circadian clock neurons in photoperiodism. This is the first finding in the neuron level that shows the involvement of the circadian clock neurons in photoperiodism.In R. pedestris, we identified four circadian clock genes, period, cycle, vrille and cryptochrome2. However, there were no distinctive daily fluctuations in the expression of these genes, and no difference between the photoperiodic conditions. In P. terraenovae, two .circadian clock genes, period and timeless showed similar daily fluctuation in the expression, but no photoperiodic difference between the photoperiodic conditions. It has been proposed based on the experimental result obtained in other insect species that the expression pattern of circadian clock genes plays an important role in photoperiodism. However, this is not plausible in these two species, and we have to examine other mechanisms for molecular mechanisms in photoperiodism. Less