Sky compass signaling of central-complex neurons in locusts exposed to the natural sky

暴露于自然天空的蝗虫中央复合体神经元的天空罗盘信号

• 批准号: 324663851
• 负责人: Professor Dr. Uwe Homberg
• 金额: --
• 依托单位: Arbeitsgruppe Neurobiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/324663851?language=en
• 关键词: Sky; compass; signaling; central; complex

Many insects, like vertebrates, can exploit celestial cues for the coding of compass orientation. Studies in honeybees, desert ants, beetles, and monarch butterflies showed that the position of the sun, the spectral gradient across the sky, and the polarization pattern of the blue sky can serve as compass cues. Analysis of polarization-sensitive neurons, especially in the desert locust, but also in beetles, the monarch butterfly, and the field cricket, showed that the central complex in the brain plays a key role in sky compass orientation. Unfortunately, the complex pattern of sky polarization, as well as the chromatic and intensity gradient in the sky cannot be mimicked faithfully in the laboratory. Therefore, we will study the activity of polarization-sensitive neurons of the central complex under the open sky. Toward this goal we will perform extracellular recordings via wire electrodes implanted in the brain of desert locusts. Activity of a neuron will be monitored first in the laboratory during rotation of the animal below stationary polarized light provided from the zenith and a dorso-lateral light source mimicking the sun. The animal will then be transferred to an observation platform on the rooftop of the institute. Under the natural sky the activity of the same neuron will be studied again during rotation of the animal around its vertical axis. Various manipulations such as painting over parts of the eyes, covering the eyes with a diffuser or studying neural activity before and after sunset will address the question of which parameters of the sky and which eye regions contribute to neural compass coding. Finally, the contribution of landmarks to direction coding in the central complex will be addressed. The study is the first to investigate sky compass neurons under natural conditions in any animal and will allow us to critically evaluate the validity of data obtained in laboratory settings.

许多昆虫，像脊椎动物一样，可以利用天体线索来编码罗盘方向。对蜜蜂、沙漠蚂蚁、甲虫和帝王蝶的研究表明，太阳的位置、天空的光谱梯度和蓝天的偏振模式都可以作为指南针的线索。对极化敏感神经元的分析，特别是在沙漠蝗虫中，也在甲虫，帝王蝶和田野蟋蟀中，表明大脑中的中央复合体在天空罗盘定位中起着关键作用。不幸的是，天空偏振的复杂模式，以及天空中的色彩和强度梯度，无法在实验室中忠实地模仿。因此，我们将在开放天空下研究中枢复合体极化敏感神经元的活动。为了实现这一目标，我们将通过植入沙漠蝗虫大脑中的电极丝进行细胞外记录。首先在实验室中，在动物在天顶提供的固定偏振光和模仿太阳的背侧光源下旋转期间，监测神经元的活动。然后，这只动物将被转移到研究所屋顶的观察平台上。在自然天空下，当动物绕其垂直轴旋转时，将再次研究同一神经元的活动。各种各样的操作，如在眼睛的部分上绘画，用漫射器覆盖眼睛或研究日落前后的神经活动，将解决天空的哪些参数和眼睛区域对神经罗盘编码有贡献的问题。最后，地标的贡献，在中央复合体的方向编码将得到解决。这项研究是第一次在任何动物的自然条件下研究天空罗盘神经元，并将使我们能够批判性地评估在实验室环境中获得的数据的有效性。