Even after decades of gaze, biologists are still finding surprises.
Researchers at the University of Virginia and the National Institutes of Health have discovered a new organelle called semi-viscosoids. This tiny membrane-bound structure is a cell recovery center and may be key to the treatment of a variety of genetic diseases. The study has been published in Natural Communication.
“It’s like discovering a new recycling center in a cell,” said Seham Ebrahim, a biophysicist at the University of Virginia, in a statement. “We believe the lower half of the stick helps manage the way cells pack and process materials, and when this process is problematic, it can help affect many systems in the body.”
Scientists have not determined the structure before, because it only appears when needed. But thanks to cryo-electron tomography, an imaging technique that can flash cells and capture them in 3D and almost atomic resolutions—the researchers were able to observe transient structures.
The researchers say the semiadhes may help form cell vesicles, small vesicles that shuttle and bind material throughout the cell. Studies have shown that they may also contribute to the formation of other organelles composed of multiple vesicles. However, some evidence suggests that semi-adhesives are not involved in endocytosis, a traditional way for cells to phagocytize external substances.
“You can think of vesicles like a small delivery truck in a cell,” Ebrahim said in a statement. “The lower half of the bond is like a loading dock where they connect and transfer goods. This is a step in the process we don’t know.”
Despite its transient nature, semi-adhesives are not uncommon. They seem common in certain parts of the cell, especially near the cell membrane.
Still, scientists are not sure how or why the semi-adhesive bodies form and then disappear. They want to find this – to understand what happens when a semi-fixed body doesn’t function properly. The question of how cells handle cargo is the root cause of many genetic diseases.
“This is just the beginning,” Ebrahim said in a statement. “Now that we know semi-adhesomes exist, we can start asking them how they behave in healthy cells and what happens when problems occur. This could lead us to develop new strategies for treating complex genetic diseases.”
