The mammalian nose, a marvel of evolution, contains millions of nerve cells, each equipped with a unique receptor for detecting specific odors, allowing humans to identify a trillion distinct scents. Columbia’s Zuckerman Institute researchers found that this intricate system influences various aspects of life, such as food choices, recognizing individuals, and triggering memories.
Unraveling the mystery of how sensory cells in the nose select their receptors has long puzzled researchers, according to Dr. Stavros Lomvardas. Lomvardas sheds light on the intricate story of olfaction, unveiling a clearer and more dramatic understanding of our sense of smell in a recent study.
In the intricate world of olfaction, specific neurons in our noses exhibit exclusive sensitivity to distinct odorants like ethyl vanillin or limonene. Described as a “Squid Games-style” competition in the nucleus of each neuron, a multitude of olfactory receptor genes compete until a single winner is determined, shaping the cell’s sensitivity.
Lead author and MD-PhD candidate at the Zuckerman Institute within the Lomvardas lab Ariel Pourmorady explained that the competition involves around 1000 contenders. This intricate procedure encompasses diverse gene-regulating molecules that stimulate or hinder olfactory receptor production. These molecules collaborate to activate or deactivate specific genes.
Dr. Lomvardas’s team identified a genomic region named “Greek Islands” that acts as molecular hubs, shaping the genome and influencing the preference for certain receptor genes. In addition to its role in protein translation, RNA appears pivotal in altering genome structure, amplifying the expression of specific olfactory receptor genes while inhibiting others.
The genome’s spatial organization in the nucleus plays a crucial role in gene expression, particularly for olfactory receptors. Pourmorady emphasizes the significance of structural changes in this process for maturing olfactory cells, highlighting the importance of understanding these mechanisms.
Advancements in molecular and genomic observations within a cell’s nucleus are pushing the boundaries of science fiction, according to Dr. Lomvardas. He emphasizes the need to delve deeper into the olfaction puzzle by continuing research into the intricate details of cellular processes.