Mitochondria, which exist within human cells but have their own DNA, need many different proteins to function — but the process of how they get these has never been imaged in detail.
Now a study led by Dr Vicki Gold, of the University of Exeter, has shown that some ribosomes — the tiny factories of cells which produce proteins — are attached to mitochondria. This can explain how proteins are pushed into mitochondria whilst they are being made.
The findings open new avenues for studying protein targeting and mitochondrial dysfunction, which has been implicated in diseases including cancer and neurodegenerative disorders such as Parkinson’s.
“Proteins are responsible for nearly all cellular processes. The cell has to make a huge variety of proteins and target them to the precise location where they are needed to function,” said Dr Gold, of Exeter’s Living Systems Institute. Paper. (public access) – Vicki AM Gold, Piotr Chroscicki, Piotr Bragoszewski, Agnieszka Chacinska. Visualization of cytosolic ribosomes on the surface of mitochondria by electron cryo tomography. EMBO reports, 2017; e201744261 DOI: 10.15252/embr.201744261 More.
It all just happened of course, the way every problem in the world accidentally solves itself.
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