Orco Protein Found Essential for Ants’ Sense of Smell and Neuron Survival

Photo byPhoto by Guillaume de Germain on Unsplash

A study by researchers from New York University and the University of Florida has shed light on the crucial role of the Orco protein in ants' olfactory systems. This protein is essential not only for the function but also for the survival of olfactory neurons in ants.

Ants use their highly developed sense of smell for communication, relying on around 400 odorant receptors. The study, published in Science Advances, found that mutating the orco gene in Harpegnathos saltator ants significantly reduced olfactory neurons. This suggests that Orco is vital for developing and maintaining these neurons.

Researchers used advanced techniques, including single-nucleus gene expression profiling and fluorescence microscopy, to analyze the olfactory cells. They observed that in mutant ants lacking Orco, the initial development of olfactory neurons appeared normal. However, these cells began to die off due to stress caused by an inability to transport odorant receptors to the cell membrane properly. This resulted in the clogging of cellular organelles and subsequent cell death.

Interestingly, some odorant receptors persisted in the absence of Orco, and these were found in non-olfactory cells like mechanosensory neurons and glia. This might indicate a potential new function for these receptors in cells not traditionally associated with smell.

The study highlights that understanding the role of Orco in ants can provide insights into the broader mechanisms of sensory development and social communication. It also opens the door to exploring potential new functions of odorant receptors beyond their traditional roles in smell.