Video Experimental Relacionado
Updated: May 21, 2026
04:43
Visualizing Visual Adaptation
Published on: April 24, 2017
Visión del color: regla "OH-site" para ver rojo y verde
Sivakumar Sekharan1, Kota Katayama, Hideki Kandori
1Cherry L. Emerson Center for Scientific Computation, Department of Chemistry, Emory University, Atlanta Georgia 30322, USA. ssekhar@emory.edu
Journal of the American Chemical Society
|June 6, 2012
Resumen
La regla del "sitio OH" explica cómo los aminoácidos que contienen hidroxilo sintonizan los pigmentos visuales del mono para la percepción del color rojo y verde. Esta regla específica del sitio se aplica a varios pigmentos visuales en todas las especies.
Área de la Ciencia:
- La biofísica es la biofísica.
- Biología Molecular Biología Molecular
- Visión Visión Ciencia Ciencia.
Sus antecedentes:
- La visión del color es crucial para la supervivencia de los animales, ayudando en la búsqueda de alimento y la navegación.
- Los pigmentos visuales, compuestos de retina y opsina, son responsables de la detección de luz y la percepción del color.
- Comprender los mecanismos moleculares del ajuste espectral es clave para comprender la visión del color.
Objetivo del estudio:
- Analizar teóricamente la estructura y el mecanismo molecular del ajuste espectral en los pigmentos visuales sensibles al rojo y al verde de los monos.
- Investigar el papel de los aminoácidos con hidroxilo en la modulación de la longitud de onda de absorción de la retina.
- Proponer una regla generalizable para predecir los cambios espectrales en los pigmentos visuales.
Principales métodos:
- Utilizó el método ONIOM (QM/MM) para un análisis teórico completo.
- Se analizó la interacción entre los aminoácidos portadores de hidroxilo de la retina y los aminoácidos específicos (A164S, F261Y, A269T) cerca del anillo β-ionona.
- Se examinaron los desplazamientos espectrales en las opsinas de bovinos y calamares que involucran aminoácidos con hidroxilo cerca de la base de Schiff.
Principales resultados:
- Interacciones identificadas de retinal con tres aminoácidos portadores de hidroxilo que aumentan la deslocalización de electrones y disminuyen la alternancia de la longitud del enlace.
- Se demostró que estas interacciones causan variaciones en la longitud de onda de absorción máxima de la retina, lo que lleva a la percepción del color rojo y verde.
- Valida la regla propuesta de "sitio OH" prediciendo con precisión los desplazamientos espectrales en diferentes pigmentos visuales, incluidas las opsinas de bovinos y calamares.
Conclusiones:
- La regla del "sitio OH" explica efectivamente el ajuste espectral para la visión de color rojo y verde en los primates.
- La regla es específica del sitio y aplicable a diferentes especies y pigmentos visuales, no limitado a los monos.
- Este hallazgo proporciona una herramienta valiosa para el seguimiento de los cambios espectrales y la comprensión de los mecanismos de percepción del color en diversos sistemas visuales.
Videos de Conceptos Relacionados
01:24Color Vision
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.
01:22Photoreceptors and Visual Pathways
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, whereas...
01:20Anatomy of the Eyeball
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 layer, the vascular tunic,...
03:02Colors and Magnetism
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
01:24Vision
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.
01:32The Retina
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.