Verasztó Csaba, Jasek Sanja, Gühmann Martin, Bezares-Calderón Luis Alberto, Williams Elizabeth A, Shahidi Réza, Jékely Gáspár
Living Systems Institute, University of Exeter, Exeter, United Kingdom.
École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Elife. 2025 Aug 27;13:RP97964. doi: 10.7554/eLife.97964.
Nervous systems coordinate effectors across the body during movements. We know little about the cellular-level structure of synaptic circuits for such body-wide control. Here, we describe the whole-body synaptic connectome of a segmented larva of the marine annelid . We reconstructed and annotated over 9000 neuronal and non-neuronal cells in a whole-body serial electron microscopy dataset. Differentiated cells were classified into 202 neuronal and 92 non-neuronal cell types. We analyse modularity, multisensory integration, left-right, and intersegmental connectivity and motor circuits for ciliated cells, glands, pigment cells, and muscles. We identify several segment-specific cell types, demonstrating the heteromery of the annelid larval trunk. At the same time, segmentally repeated cell types across the head, the trunk segments and the pygidium suggest the serial homology of all segmental body regions. We also report descending and ascending pathways, peptidergic circuits, and a multimodal mechanosensory girdle. Our work provides the basis for understanding whole-body coordination in an entire segmented animal.
神经系统在运动过程中协调全身的效应器。对于这种全身控制的突触回路的细胞水平结构，我们了解甚少。在这里，我们描述了一种海洋环节动物分段幼虫的全身突触连接组。我们在一个全身连续电子显微镜数据集中重建并注释了9000多个神经元和非神经元细胞。分化细胞被分为202种神经元和92种非神经元细胞类型。我们分析了模块化、多感觉整合、左右和节间连接以及纤毛细胞、腺体、色素细胞和肌肉的运动回路。我们识别出几种特定节段的细胞类型，证明了环节动物幼虫躯干的异质性。同时，头部、躯干节段和尾节上节段重复的细胞类型表明所有节段身体区域的序列同源性。我们还报告了下行和上行通路、肽能回路以及多模式机械感觉带。我们的工作为理解整个分段动物的全身协调提供了基础。
