相关实验视频
Updated: Jun 10, 2025

04:43
Visualizing Visual Adaptation
Published on: April 24, 2017
8.9K
一种形视觉颜料的并行光谱调节提供了关于鱼古代深海适应的证据
Hai Chi1, Linxia Sun2, Na Li1
1College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi, China.
Genome biology and evolution
|October 13, 2024
概括
鱼的视力从二色演变为单色,主要视觉颜料的损失. 祖先的色素分析揭示了向更短的波长转移,可能是为了在进一步视力丧失之前适应深海.
科学领域:
- 进化生物学是进化的生物学.
- 进行比较的基因组学.
- 视觉科学 视觉科学 视觉科学
背景情况:
- 许多哺乳动物通过两个圆色素具有双色彩视觉.
- 早期的类动物失去了紫色敏感的颜料,导致单色的形视力.
- 随后的中/长波长敏感 (M/LWS) 颜料的损失导致许多鱼系的杆单色视力.
研究的目的:
- 研究鱼视觉颜料的表型演变,特别是M/LWS和Rhodopsin (RH1).
- 了解鱼进化过程中M/LWS色素的光谱调和功能变化.
- 探索与深海环境相关的潜在适应.
主要方法:
- 评估了来自代表性鱼种群的M/LWS和RH1色素的光谱调整.
- 在实验室中对M/LWS色素敏感性进行了皮格米右和贝尔德的嘴的分析.
- 利用祖先序列重建来复活和功能性地测量古老的M/LWS色素.
主要成果:
- M/LWS编码序列在矮人右和贝尔德的型鱼中是完整的,但非功能性的,这表明形视力丧失.
- 来自白祖先的祖先M/LWS色素显示出绿色灵敏度,40纳米转移到更短的波长.
- 精卵祖先的M/LWS色素虽然是非功能性的,但很可能经历了20-30纳米的转移到更短的波长.
结论:
- 鱼视觉色素的演变显示了M/LWS对较短波长的敏感性的平行转移.
- 这些光谱变化可能代表了祖先鱼对深海活动增加的适应.
- 随后的生态因素可能导致了某些基因系中功能性M/LWS色素的完全丧失.
相关概念视频
Photoreceptors and Visual Pathways
5.8K
At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category,...
5.8K
Color Vision
535
Color perception begins in the retina, the light-sensitive layer at the back of the eye. Two main theories explain how colors are seen: the trichromatic theory and the opponent-process theory. The trichromatic theory, proposed by Thomas Young in 1802 and extended by Hermann von Helmholtz in 1852, suggests that color vision is based on three types of cone receptors in the retina. These cones are sensitive to different but overlapping ranges of wavelengths corresponding to red, blue, and green.
535
Depth Perception and Spatial Vision
601
Depth perception is the ability to perceive objects three-dimensionally. It relies on two types of cues: binocular and monocular. Binocular cues depend on the combination of images from both eyes and how the eyes work together. Since the eyes are in slightly different positions, each eye captures a slightly different image. This disparity between images, known as binocular disparity, helps the brain interpret depth. When the brain compares these images, it determines the distance to an object.
601
Channel Rhodopsins
2.5K
Most organisms use photoreceptors to sense and respond to light. Examples of photoreceptors include bacteriorhodopsins and bacteriophytochromes in some bacteria, phytochromes in plants, and rhodopsins in the photoreceptor cells of the vertebral retina. The light-sensitive property of these receptors is because of the bound chromophores, such as bilin in the phytochromes and retinal in the rhodopsins.
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
2.5K

