Wei Huayi, Kyung Ha Young, Kim Priscilla J, Desplan Claude
Department of Biology, New York University, New York, NY, USA.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2020 Mar;206(2):139-148. doi: 10.1007/s00359-019-01380-y. Epub 2019 Nov 11.
To navigate through the environment, animals rely on visual feedback to control their movements relative to their surroundings. In dipteran flies, visual feedback is provided by the wide-field motion-sensitive neurons in the visual system called lobula plate tangential cells (LPTCs). Understanding the role of LPTCs in fly behaviors can address many fundamental questions on how sensory circuits guide behaviors. The blowfly was estimated to have ~ 60 LPTCs, but only a few have been identified in Drosophila. We conducted a Gal4 driver screen and identified five LPTC subtypes in Drosophila, based on their morphological characteristics: LPTCs have large arborizations in the lobula plate and project to the central brain. We compared their morphologies to the blowfly LPTCs and named them after the most similar blowfly cells: CH, H1, H2, FD1 and FD3, and V1. We further characterized their pre- and post-synaptic organizations, as well as their neurotransmitter profiles. These anatomical features largely agree with the anatomy and function of their likely blowfly counterparts. Nevertheless, several anatomical details indicate the Drosophila LPTCs may have more complex functions. Our characterization of these five LPTCs in Drosophila will facilitate further functional studies to understand their roles in the visual circuits that instruct fly behaviors.
为了在环境中导航，动物依靠视觉反馈来控制其相对于周围环境的运动。在双翅目苍蝇中，视觉反馈由视觉系统中称为小叶板切向细胞（LPTCs）的广域运动敏感神经元提供。了解LPTCs在苍蝇行为中的作用可以解决许多关于感觉回路如何引导行为的基本问题。据估计，家蝇有大约60个LPTCs，但在果蝇中只鉴定出了少数几个。我们进行了一项Gal4驱动筛选，并根据其形态特征在果蝇中鉴定出五种LPTC亚型：LPTCs在小叶板中有大的分支，并投射到中枢脑。我们将它们的形态与家蝇LPTCs进行了比较，并以最相似的家蝇细胞命名：CH、H1、H2、FD1和FD3，以及V1。我们进一步表征了它们的突触前和突触后组织，以及它们的神经递质谱。这些解剖学特征在很大程度上与它们可能的家蝇对应物的解剖学和功能一致。然而，一些解剖学细节表明果蝇LPTCs可能具有更复杂的功能。我们对果蝇中这五种LPTCs的表征将有助于进一步的功能研究，以了解它们在指导果蝇行为的视觉回路中的作用。
