The findings, they write, may also have implications for the regulating of olfactory receptors, which are responsible for the detection of smells, because both types of receptors belong to the same protein family.
Biologists have previously found that most sensory systems follow the “one receptor molecule per receptor cell” rule. For example, photoreceptors in the fly eye and human cones—our color-sensitive photoreceptors—each express only one rhodopsin, a pigment that is sensitive to only one color. Rhodopsins are G-coupled protein receptors, a class of ancient signaling molecules that mediate not just vision, but also the sense of smell and other physiological processes.
In the PloS Biology study, the NYU researchers examined the eye of the fruit fly Drosophila. Fruit flies can be analyzed and manipulated in exquisite details by biologists and serve as a powerful model system to understand biological processes such as vision. In each of the estimated 800 individual facets that make up the fly eye, there are eight photoreceptors (R1–R8). Six of these mediate broad-spectrum detection of motion (R1–R6) and two mediate color vision (R7 and R8) and are similar to the human cone photoreceptors.
The NYU researchers, headed by Biology Professor Claude Desplan, sought to understand the mechanisms that regulate mutual exclusion of rhodopsin photoreceptor genes in the fly retina, which is poorly understood. Their results revealed a new class of photoreceptors that violates the one rhodopsin–one photoreceptor rule. This new class, located in the dorsal third of the eye, co-expresses two ultraviolet (UV)-sensitive rhodopsins (rh3 and rh4) in R7, while maintaining discrimination between green and blue rhodopsins in R8.
The NYU researchers found that this co-expression depends on a group of genes—the so-called Iroquois Complex genes—that are known to specify the dorsal side of the eye. These genes are necessary and sufficient to allow the two UV-sensitive rhodopsins to be expressed in the same R7 cell. The purpose of this co-expression of UV-sensitive pigments in a specialized part of the dorsal retina is likely to allow the flies to better orient to the sun for navigation: Flies, like bees, where this has been well documented, can discriminate between the solar side of the landscape, which has fewer radiations in the UV, and the opposite side (anti-solar), which is very UV-rich.
James Devitt | EurekAlert!
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine