Video Experimental Relacionado
Updated: Jul 11, 2026
07:48
A Method for Lineage Tracing of Corneal Cells Using Multi-color Fluorescent Reporter Mice
Published on: December 18, 2015
La expresión estocástica sin columna vertebral crea el mosaico retiniano para la visión en color
Mathias F Wernet1, Esteban O Mazzoni1, Arzu Çelik1
1Center for Developmental Genetics, Department of Biology, New York University, 100 Washington Place, New York, New York 10003, USA.
Nature
|March 10, 2006
Resumen
El receptor de dioxina de Drosophila Spineless es crucial para crear el mosaico retiniano esencial para la visión en color. Su expresión en las células R7 determina si los ommatidios se convierten en ommatidios.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Biología del desarrollo Biología del desarrollo.
- Genética La genética.
Sus antecedentes:
- La visión del color de Drosophila depende de las células fotorreceptoras R7 y R8 dentro de los ommatidios.
- Existen dos subtipos ommatidiales, "pálido" y "amarillo", determinados por la expresión distinta de la rodopsina.
- Estos subtipos se distribuyen estocásticamente a través de la retina, de manera similar a los fotorreceptores de cono humanos.
Objetivo del estudio:
- Identificar los mecanismos moleculares que rigen la formación estocástica de los subtipos ommatidiales retinales de Drosophila.
- Para investigar el papel del receptor de dioxina Spineless en el establecimiento del mosaico ommatidial pálido y amarillo.
Principales métodos:
- Análisis de mutantes sin columna vertebral (ss) para observar los efectos en el destino celular R7 y R8.
- Estudios de sobreexpresión de espinales en células R7 para evaluar su suficiencia en la determinación del destino.
- Análisis temporal de la expresión espinosa durante la pupación en relación con la expresión de la rodopsina.
Principales resultados:
- Sin columna vertebral es necesario para la formación del mosaico ommatidial; los mutantes sin columna vertebral exhiben un destino "pálido" uniforme en las células R7 y R8.
- Un estallido transitorio de expresión sin columna vertebral en las células R7 precede a la expresión de rodopsina, dictando el subtipo ommatidial.
- La sobreexpresión de la espina dorsal es suficiente para inducir el destino de las células R7 "amarillas", anulando el destino "pálido" predeterminado.
Conclusiones:
- El factor de transcripción Spineless es a la vez necesario y suficiente para establecer el mosaico ommatidial estocástico en Drosophila.
- Un solo factor de transcripción, Spineless, controla todo el mosaico retiniano requerido para la visión en color de Drosophila.
- Este hallazgo proporciona una visión clave de la regulación genética de la formación del mosaico sensorial.
Videos de Conceptos Relacionados
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.
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.
01:20The Retinoblastoma Gene
Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
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,...
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...
01:24Color 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.