Study finds new cellular component important for sense of smell

Researchers at Umea University in Sweden have discovered an organelle, a previously unexplained cellular component, in the neurons that our nostrils use to perceive scent. The finding could encourage more research on the COVID-19 symptom of impaired scent perception.

“A prerequisite for finding a treatment for impaired sense of smell is to first understand how the sense of smell works, said Staffan Bohm. “Professor at Umea University’s department of molecular biology. The so-called organelle that the researchers have discovered has never been observed inside of a nerve cell before. The newly identified organelle is known by the term multivesicular transducosome, according to the researchers.

The unique microscope facilities at Umea University played a significant role in the finding.
The so-called organelle that the researchers have found inside nerve cells is something that has never before been seen. The researchers have named the recently found organelle the multivesicular transducosome. The discovery was made feasible by the unique microscope equipment at Umea University.

Organelles are discrete “workstations” within cells that are comparable to the various bodily organs in that they each serve a unique purpose within the cell. The majority of organelles are shared by several cell types, however certain organelles have particular functions that are found only in particular cell types.

Long projections, known as cilia, emerge from olfactory nerve cells into the nasal cavity, where they carry the proteins that bind odorous molecules and trigger nerve signals to the brain. Transduction is the process of turning smells into nerve impulses, and the newly found organelle solely includes transduction proteins.

The transductosome’s job is to store and maintain the segregation of transduction proteins until they are required. Olfactory stimulation causes the organelle’s outer membrane to burst, releasing the transduction proteins so they can go to the cilia of the neuron and causing scent to be sensed. The researchers also found that a protein known as retinitis pigmentosa 2 (RP2), which is normally known to control transduction in the eye’s photoreceptor cells, is carried by the transductosome.

Retinitis pigmentosa is a type of eye illness that affects the light-sensitive cells of the eye and can be brought on by mutations in the RP2 gene.

“The role of the transductosome in vision and its presence in brain neurons that are triggered by neurotransmitters rather than light and scent are questions that require additional study. If that’s the case, the finding might be even more important “Staffan Bohm added.

Using a novel method called correlative microscopy, researcher Devendra Kumar Maurya found the transducosome. The method combines confocal and electron microscopy to simultaneously view the internal architecture of a cell and the locations of several proteins.

Devendra’s method creation, which allowed the approach to be utilised to analyse intact neurons in tissue slices, was essential to the finding.