Ruperti Fabian, Becher Isabelle, Stokkermans Anniek, Wang Ling, Marschlich Nick, Potel Clement, Maus Emanuel, Stein Frank, Drotleff Bernhard, Schippers Klaske, Nickel Michael, Prevedel Robert, Musser Jacob M, Savitski Mikhail M, Arendt Detlev
Developmental Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany.
Collaboration for joint Ph.D. degree between EMBL and Heidelberg University, Faculty of Biosciences 69117 Heidelberg, Germany.
bioRxiv. 2023 Aug 2:2023.08.02.551666. doi: 10.1101/2023.08.02.551666.
A hallmark of animals is the coordination of whole-body movement. Neurons and muscles are central to this, yet coordinated movements also exist in sponges that lack these cell types. Sponges are sessile animals with a complex canal system for filter-feeding. They undergo whole-body movements resembling "contractions" that lead to canal closure and water expulsion. Here, we combine 3D optical coherence microscopy, pharmacology, and functional proteomics to elucidate anatomy, molecular physiology, and control of these movements. We find them driven by the relaxation of actomyosin stress fibers in epithelial canal cells, which leads to whole-body deflation via collapse of the incurrent and expansion of the excurrent system, controlled by an Akt/NO/PKG/A pathway. A concomitant increase in reactive oxygen species and secretion of proteinases and cytokines indicate an inflammation-like state reminiscent of vascular endothelial cells experiencing oscillatory shear stress. This suggests an ancient relaxant-inflammatory response of perturbed fluid-carrying systems in animals.
动物的一个显著特征是全身运动的协调性。神经元和肌肉对此至关重要，但在缺乏这些细胞类型的海绵中也存在协调运动。海绵是固着动物，具有用于滤食的复杂管道系统。它们会进行类似“收缩”的全身运动，导致管道关闭和水排出。在这里，我们结合三维光学相干显微镜、药理学和功能蛋白质组学来阐明这些运动的解剖结构、分子生理学和控制机制。我们发现这些运动是由上皮管道细胞中肌动球蛋白应力纤维的松弛驱动的，这通过流入系统的塌陷和流出系统的扩张导致全身放气，由Akt/NO/PKG/A途径控制。活性氧的同时增加以及蛋白酶和细胞因子的分泌表明存在一种类似炎症的状态，让人联想到经历振荡剪切应力的血管内皮细胞。这表明动物中受干扰的流体输送系统存在一种古老的松弛 - 炎症反应。
