Odour transduction in olfactory receptor neurons
Jean-Pierre Rospars1, Yuqiao Gu, Alexandre Grémiaux
1INRA, UMR 1272 Physiologie de l'Insecte: Signalisation et Communication, Versailles, France. jean-pierre.rospars@versailles.inra.fr
The Chinese Journal of Physiology
|July 29, 2011
Summary
This review compares olfactory signaling mechanisms in vertebrates and insects, focusing on odorant receptor binding and signal transduction for various chemical signals. Future research should explore computational modeling of these complex olfactory systems.
Area of Science:
- Neuroscience
- Molecular Biology
- Biochemistry
Background:
- Olfactory receptors (ORs) detect diverse odorants, initiating signal transduction pathways.
- Signal transduction converts odorant binding into cellular responses like membrane depolarization.
- Interspecific (allelochemicals) and intraspecific (pheromones) signals involve distinct molecular mechanisms.
Purpose of the Study:
- To review and compare molecular mechanisms of olfactory signal transduction.
- To examine differences and similarities between vertebrate and insect olfactory systems.
- To explore the development of quantitative models for olfactory signaling networks.
Main Methods:
- Literature review of molecular mechanisms in olfaction.
- Comparative analysis of olfactory signal transduction in vertebrates and insects.
- Discussion of computational approaches and modeling attempts.
Main Results:
- Detailed comparison of odorant-OR binding and downstream signaling in vertebrates and insects.
- Identification of conserved and divergent molecular players in olfactory transduction.
- Overview of current challenges and limitations in quantitative olfactory modeling.
Conclusions:
- Olfactory signal transduction shares fundamental principles across species but exhibits significant variations.
- Quantitative modeling of olfactory networks is complex and requires further development.
- Computational analysis of olfaction represents a promising frontier for future research.
Related Concept Videos
01:20Physiology of Smell and Olfactory Pathway
Humans detect odors with the help of specialized cells located in the upper part of the nasal cavity, called olfactory receptor neurons (ORNs). ORNs possess hair-like structures called cilia, which are receptive to sensations from the inhaled air. When an odorant molecule binds to a specific receptor on the cell of the cilia, it leads to a series of events that ultimately cause the ORN to send electrical signals to the olfactory bulb in the brain through the olfactory nerves.
The olfactory...
The olfactory...
01:03Olfactory Receptors: Location and Structure
The process of olfaction, also known as the sense of smell, is a sophisticated chemical response system. The specialized sensory neurons that facilitate this process, known as olfactory receptor neurons, are situated in an upper segment of the nasal cavity, known as the olfactory epithelium. Olfactory sensory neurons are bipolar, with their dendrites extending from the epithelium's apex into the mucus that lines the nasal cavity. Airborne molecules, when inhaled, traverse the olfactory...
01:25Olfaction
The sense of smell is achieved through the activities of the olfactory system. It starts when an airborne odorant enters the nasal cavity and reaches olfactory epithelium (OE). The OE is protected by a thin layer of mucus, which also serves the purpose of dissolving more complex compounds into simpler chemical odorants. The size of the OE and the density of sensory neurons varies among species; in humans, the OE is only about 9-10 cm2.
The olfactory receptors are embedded in the cilia of the...
The olfactory receptors are embedded in the cilia of the...
01:21G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
01:27Tactile and Chemical Senses
Tactile senses encompass touch, temperature, and pain, each mediated by specific receptors. Touch receptors detect mechanical energy or pressure against the skin. Sensory fibers from these receptors enter the spinal cord and relay information to the brain stem. Here, most fibers cross over to the opposite side of the brain. The touch information then moves to the thalamus, which projects a map of the body's surface onto the somatosensory areas of the parietal lobes in the cerebral cortex. This...
01:26Introduction to Special Senses
Sensory receptors play an integral part in comprehending our external and internal environments. They receive diverse stimuli, converting them into the nervous system's electrochemical signals. This conversion occurs as the stimulus alters the sensory neuron's cell membrane potential, instigating the generation of an action potential. This action potential is subsequently transmitted to the central nervous system (CNS), which integrates with other sensory data or higher cognitive functions.