Evans Anastasiia, Ferrer Anggie J, Fradkov Erica, Shomar Joseph W, Forer Josh, Klein Mason
Department of Physics, University of Miami, Coral Gables, FL, United States.
Department of Biology, University of Miami, Coral Gables, FL, United States.
Front Mol Neurosci. 2023 Oct 27;16:1275469. doi: 10.3389/fnmol.2023.1275469. eCollection 2023.
The surrounding thermal environment is highly important for the survival and fitness of animals, and as a result most exhibit behavioral and neural responses to temperature changes. We study signals generated by thermosensory neurons in larvae and also the physical and sensory effects of temperature variation on locomotion and navigation. In particular we characterize how sensory neuronal and behavioral responses to temperature variation both change across the development of the larva. Looking at a wide range of non-nociceptive isotropic thermal environments, we characterize the dependence of speed, turning rate, and other behavioral components on temperature, distinguishing the physical effects of temperature from behavior changes based on sensory processing. We also characterize the strategies larvae use to modulate individual behavioral components to produce directed navigation along thermal gradients, and how these strategies change during physical development. Simulations based on modified random walks show where thermotaxis in each developmental stage fits into the larger context of possible navigation strategies. We also investigate cool sensing neurons in the larva's dorsal organ ganglion, characterizing neural response to sine-wave modulation of temperature while performing single-cell-resolution 3D imaging. We determine the sensitivity of these neurons, which produce signals in response to extremely small temperature changes. Combining thermotaxis results with neurophysiology data, we observe, across development, sensitivity to temperature change as low as a few thousandths of a °C per second, or a few hundredths of a °C in absolute temperature change.
周围的热环境对动物的生存和适应性至关重要，因此大多数动物都会对温度变化表现出行为和神经反应。我们研究幼虫中热感觉神经元产生的信号，以及温度变化对运动和导航的物理和感官影响。特别是，我们描述了幼虫发育过程中感觉神经元和行为对温度变化的反应是如何变化的。在广泛的非伤害性各向同性热环境中，我们描述了速度、转弯速率和其他行为成分对温度的依赖性，区分了温度的物理影响和基于感官处理的行为变化。我们还描述了幼虫用来调节个体行为成分以沿热梯度进行定向导航的策略，以及这些策略在身体发育过程中是如何变化的。基于修正随机游走的模拟显示了每个发育阶段的趋温性在可能的导航策略的更大背景中的位置。我们还研究了幼虫背器官神经节中的冷感觉神经元，在进行单细胞分辨率三维成像时，描述其对温度正弦波调制的神经反应。我们确定了这些神经元的敏感性，它们会对极小的温度变化产生信号。将趋温性结果与神经生理学数据相结合，我们观察到，在整个发育过程中，对温度变化的敏感性低至每秒千分之几度，或绝对温度变化百分之几度。
