据介绍,光通过内在光敏视网膜神经节细胞(ipRGC)发送到大脑的信号来调节生理、情绪和行为。灵长类动物的ipRGC如何感知光目前尚不清楚,因为它们很罕见,并且很难作为电生理记录的目标。
研究人员开发了一种在活体视网膜内进行急性识别的方法。通过这种方法,研究人员发现猕猴的ipRGC通过模糊视觉场景的空间、时间和颜色特征,高度特化地编码辐照度(照明的总体强度)。研究人员描述了分子、细胞和种群尺度上的机制,这些机制支持辐照度编码跨越光强的数量级变化。
总之,这些机制在数量上是保守的,跨越了猕猴和小鼠之间约7千万年的演化过程。
附:英文原文
Title: Encoding of environmental illumination by primate melanopsin neurons
Author: Andreas Liu, Elliott S. Milner, Yi-Rong Peng, Hannah A. Blume, Michael C. Brown, Gregory S. Bryman, Alan J. Emanuel, Philippe Morquette, Nguyen-Minh Viet, Joshua R. Sanes, Paul D. Gamlin, Michael Tri H. Do
Issue&Volume: 2023-01-27
Abstract: Light regulates physiology, mood, and behavior through signals sent to the brain by intrinsically photosensitive retinal ganglion cells (ipRGCs). How primate ipRGCs sense light is unclear, as they are rare and challenging to target for electrophysiological recording. We developed a method of acute identification within the live, ex vivo retina. Using it, we found that ipRGCs of the macaque monkey are highly specialized to encode irradiance (the overall intensity of illumination) by blurring spatial, temporal, and chromatic features of the visual scene. We describe mechanisms at the molecular, cellular, and population scales that support irradiance encoding across orders-of-magnitude changes in light intensity. These mechanisms are conserved quantitatively across the ~70 million years of evolution that separate macaques from mice.
DOI: ade2024
Source: https://www.science.org/doi/10.1126/science.ade2024