在蝶彩色视觉中,感官受体扩张和神经适应
Ke Gao1, Julia Ainsworth1, Antoine Donati1
1Department of Cell & Developmental Biology, School of Biological Sciences, University of California San Diego, La Jolla, CA, 92093, USA.
bioRxiv : the preprint server for biology
|November 24, 2025
概括
蝶通过添加第二个R7光感受器进化了增强的色彩视觉,从而产生了三种全身类型. 大脑中的多余神经元,通常被消除,被保留以适应这种新的感官输入,推动神经进化.
科学领域:
- 神经科学是一个神经科学.
- 发展生物学 发展生物学
- 进化生物学 进化生物学
背景情况:
- 大脑进化需要整合新的神经输入,但基本的遗传和发育机制尚不清楚.
- 蝶拥有比更复杂的视觉系统,每个都有额外的R7色光受体.
- 这导致了蝶的三种形类型,与中的两种形成对比,这是由于独立的随机细胞命运选择.
研究的目的:
- 研究蝶第二个R7细胞进化背后的发育机制.
- 了解蝶大脑如何适应扩大的感官受体输入.
- 探索多余神经元在神经进化和适应中的作用.
主要方法:
- 在蝶中确定了指明第二个R7细胞的发育机制.
- 基因改造的多索菲拉视网膜模仿蝶转录因子表达,诱导额外的R7.
- 分析了经过修改的Drosophila视网膜中的神经元连接和存活率,并将它们与野生类型和蝶视网膜进行了比较.
主要成果:
- 蝶类转录因子表达在Drosophila中诱导了额外的R7,从而产生了三种具有独立随机细胞命运选择的整体类型.
- 在修改后的Drosophila中,当额外的R7s存在时,通常经历着亡的多余Dm8神经元被保留,导致每个髓柱有两个Dm8.
- 这表明,通常在发育过程中被消除的多余神经元可以被选择,以适应扩大的感官输入.
结论:
- 提出了一个模型,其中视网膜R7亚型比保持过多的脑神经元池,提供适应新输入的发育灵活性.
- 过剩的神经元的保留,通常在发育过程中被修剪,促进了蝶色彩视觉的扩展.
- 这种选择多余神经元的机制可能代表神经复杂性进化的一般原则.
相关概念视频
01:24Color Vision
1.3K
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.
1.3K
01:20Anatomy of the Eyeball
9.4K
The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle...
9.4K
01:24Vision
59.2K
Vision is the result of light being detected and transduced into neural signals by the retina of the eye. This information is then further analyzed and interpreted by the brain. First, light enters the front of the eye and is focused by the cornea and lens onto the retina—a thin sheet of neural tissue lining the back of the eye. Because of refraction through the convex lens of the eye, images are projected onto the retina upside-down and reversed.
59.2K
01:22Photoreceptors and Visual Pathways
8.7K
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,...
8.7K
01:32The Retina
74.1K
The retina is a layer of nervous tissue at the back of the eye that transduces light into neural signals. This process, called phototransduction, is carried out by rod and cone photoreceptor cells in the back of the retina.
74.1K
01:26Visual System
1.6K
Light enters the eye through the cornea, a transparent, dome-shaped surface covering the surface of the eyeball that helps to direct and focus incoming light. This light is then channeled toward the pupil, an adjustable opening whose size is controlled by the iris. The iris, a pigmented muscle, regulates the amount of light entering the eye by contracting or dilating the pupil, thereby ensuring optimal light levels for clear vision.
Once through the pupil, the light passes through the lens, a...
Once through the pupil, the light passes through the lens, a...
1.6K