Breakthrough Discovery in Mitochondrial Recycling Could Impact Health Treatments

Mitochondria, the so-called "powerhouse of the cell," depend on a newly discovered recycling mechanism identified by scientists at The Hospital for Sick Children (SickKids). 

Mitochondria are tiny structures inside of cells that carry out a wide range of critical functions, including generating energy to help keep cells healthy. Every mitochondrion has two layers of membranes: the outer membrane and the inner membrane. On the inner membrane, folds called cristae contain proteins and molecules needed for energy production. When cristae are damaged, there can be a negative impact on an entire cell. 

"Our research shows, for the first time, that mitochondria are able to recycle a localized injury, removing damaged cristae, and then function normally afterward," says Dr. Nicola Jones, Staff Physician and Senior Scientist in the Cell Biology program at SickKids and lead of the study published in Nature

In addition to being essential to keeping mitochondria healthy, the research team believe this mechanism could present a future target for the diagnosis and treatment of conditions characterized by mitochondrial dysfunction, including infection, fatty liver disease, aging, neurodegenerative conditions and cancer. 

The Mechanisms of Mitochondrial Recycling 

In cells, structures called lysosomes act as recycling centers that can digest different kinds of molecular material. With state-of-the art microscopes at the SickKids Imaging Facility, Dr. Akriti Prashar, a postdoctoral fellow in Jones' lab and first author on the paper, identified that a mitochondria's damaged crista can squeeze through its outer membrane to have a lysosome directly engulf it and break it down successfully. 

The researchers named the novel process VDIM formation, which stands for vesicles derived from the inner mitochondrial membrane. By removing damaged cristae through VDIMs, cells can prevent harm from spreading to the rest of the mitochondria and the whole cell. 

We believe that VDIMs could be a way of protecting cells from health conditions that affect mitochondria, such as cancer and neurodegeneration."

Dr. Akriti Prashar

A New Process: VDIM Formation 

The research team, including scientists at the Francis Crick Institute and Johns Hopkins University, found that forming a VDIM involved several steps and molecules. First, a damaged crista releases a signal that activates a channel on the nearby lysosome to allow calcium to flow out of the lysosome. Calcium then activates another channel on the outer membrane of the mitochondria to form a pore and allow damaged cristae to squeeze out of the mitochondria into the lysosome, which digests the damaged material – something that has never been seen before. By recycling just the damaged crista, mitochondria can continue its regular function. 

"Understanding this process gives us insight into how mitochondria stay healthy, which is important to everyone's overall health and longevity," says Prashar. 

Future research will explore how altering VDIM formation could improve symptoms or even prevent health conditions caused by underperforming or damaged mitochondria. 

This research was funded by Canadian Institutes of Health Research (CIHR) and a SickKids Restracomp fellowship. 

Source:
Journal reference:

Prashar, A., et al. (2024). Lysosomes drive the piecemeal removal of mitochondrial inner membrane. Nature. doi.org/10.1038/s41586-024-07835-w.

Comments

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of AZoLifeSciences.
Post a new comment
Post

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.

You might also like...
New Antioxidants Show Promise for Broader Cellular Protection