Scientists in the European Molecular Biology Laboratory have discovered a remarkable adaptation to starvation in yeast cells. When a yeast cell yearns for nutrients, its ribosomes begin to coat the cell’s mitochondria. It turns out these ribosomes aren’t producing anything, but rather they are in hibernation. Producing proteins requires a lot of energy, so the conservation of energy through hibernation allows the cell to survive.
Scientists were curious about why the ribosomes specifically cling to the mitochondria. One explanation is that the mitochondria could provide protection to the ribosomes. There are forms of mitochondria that can protect parts of the cell, so this is a possible outlook. Another potential explanation for the ribosomes activity is starving cells need a way to quickly start producing energy once nutrients are available again. Since mitochondria are the energy producers of the cell, having ribosomes nearby to produce necessary proteins might speed this process.
The most surprising part of this study was that the ribosomes attached to the mitochondrial outer membrane in a way that is completely different from what is known. Normally, ribosomes interact with the mitochondria via the large subunit, but in the yeast, the ribosomes were interacting with the small subunit. The research team plans to follow up this study by learning more about why this difference occurs.
This study is critical in understanding the spread of cancer cells. Cancer cells grow so rapidly that their demand for nutrients and oxygen outpaces the supply. This means most cancer cells are constantly starving themselves. Yet, they survive and multiply. If we can understand the foundations of this adaptation, maybe we can find a way to take advantage of the starving cancer cells and make them more susceptible to treatment.
This connects to AP Bio because the curriculum covers the functions of the mitochondria and ribosomes but this research shows an abnormal aspect of them. Normally, the mitochondria is the site of cell respiration, converting glucose into ATP. The enzymes that perform reactions in the matrix are embedded in the mitochondrial membrane. The ribosomes can be bound to the mitochondria while manufacturing proteins that are inserted into membranes in the cell. I just fasted for Yom Kippur, so I wonder if any of the ribosomes in my cells hibernated due to the lack of nutrients my body received. What do you think of this new discovery and its potential application?
aaribosome
Hey Mattochondrubinia, I like how this article made me think. You presented all the information well and included your own insights, but you didn’t give the reader a definite direction of where this research could take society. That open format prompted personal thought and was superb in keeping my attention. As for where I think this could go, knowledge about where the majority of ribosomes are kept in cancerous cells could allow treatments to become more targeted and therefore more effective in removing cancerous cells without negative externalities effecting healthy cells. The article you wrote about has a focus on this discovery and the implication of cancer cells with hibernating ribosomes, while this article (https://www.nature.com/articles/s41467-024-52911-4) talks about how ribosomes hibernate under nutrient deprived conditions in general. After reading both articles, I am left wondering if there are similar effects in terms of ribosome location when the cell is under the stress of extreme ATP production. If ribosomes flee to the mitochondria in those situations as well, it could lead to an explanation of why they do it when there are scarce resources: to increase the speed of ATP production when the nutrients are available, like you suggested in your blog post. However, we unfortunately must leave the discovering up to the professionals for now, and I am excited to see where this discovery takes us with so many unknowns. Thanks for blogging, Mattochondrubinia.