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Tech & Science
In an unprecedented scientific achievement that may redefine our understanding of the senses, a team of scientists has succeeded in mapping a comprehensive and precise map of olfactory receptors in the mouse nose. The study, published in the journal <strong>Cell</strong>, revealed that the sense of smell is not random as believed for decades, but follows a strict architectural system, opening new horizons for treating olfactory disorders in humans.
In an unprecedented scientific achievement that may redefine our understanding of the senses, a team of scientists has succeeded in mapping a comprehensive and precise map of olfactory receptors in the mouse nose. The study, published in the journal Cell, revealed that the sense of smell is not random as believed for decades, but follows a strict architectural system, opening new horizons for treating olfactory disorders in humans.
The study proved that olfactory receptors in the nasal lining are organized within narrow, precisely defined ranges, instead of random distribution. Dr. Sandeep Datta, from Harvard Medical School, described this system as a "sensory map" consisting of about a thousand separate ribbons of odor receptors, which helps the brain decode and interpret smells with high efficiency.
The research team relied on "single-cell sequencing" and "spatial transcriptomics" techniques to examine about 5.5 million neurons in more than 300 mice. This technical integration allowed for the identification of active genes within each cell, and the precise geographical location of each of the 1172 different receptors encoded in the mouse DNA, each specializing in a specific odor.
One of the most prominent findings of the study is the discovery that neurons carrying the same type of receptor within the nose send their signals to the same point within the olfactory bulb in the brain. This direct correspondence between the receptor's location in the nose and its center in the brain reflects an amazing level of complexity, especially since mice possess about 20 million olfactory neurons, a huge number compared to other sensory receptors.
Scientists identified a molecule known as Retinoic acid (RA) as a key factor in this organization; it acts as a guide that determines which receptor each neuron should express based on its location. Experiments showed that manipulating the levels of this acid leads to changes in receptor locations, confirming its pivotal role in shaping the sensory map of the nose.
Although the study was conducted on mice, scientists confirm that the human olfactory system closely resembles that of rodents. Researchers hope that understanding this regulatory mechanism will contribute to developing medical solutions for the problem of loss of the sense of smell, and its serious psychological and health consequences such as depression, by attempting to restore this precise system when it is damaged.
