Summary
Fusion, fission and mitophagy keep the mitochondrial population healthy.
In depth
Fusion (mitofusins, OPA1) mixes contents; fission (Drp1) isolates damaged parts; PINK1 and Parkin tag damaged mitochondria for mitophagy. Defects are implicated in Parkinson's and neuropathies.
Mitochondria form networks; fission segregates damaged regions. Mitophagy removes defective ones. Dynamics respond to energy demand.
Key idea: mitochondria are dynamic organelles, not static bean shapes.
Mitochondria are not static beans but form dynamic networks that constantly fuse, divide and move. Fusion, mediated by mitofusins (MFN1 and 2) and OPA1, lets mitochondria share contents and complement damaged DNA; fission, driven by Drp1, divides them for transport, inheritance and removal of damaged parts.
Quality control includes mitophagy, in which PINK1 accumulates on damaged mitochondria that have lost membrane potential, recruits Parkin and flags them for autophagy. Defects in these pathways are linked to Parkinson disease, optic atrophy (OPA1) and Charcot-Marie-Tooth disease. Mitochondria also contact the ER and other organelles.
Example: neurons need mitochondria transported along long axons.
Frequently asked questions
What is Mitochondrial Dynamics?
Fusion, fission and mitophagy keep the mitochondrial population healthy.
Which area of biology covers Mitochondrial Dynamics, and how advanced is it?
Mitochondrial Dynamics is one of the 53 topics in Metabolism & Bioenergetics. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Proton Motive Force, Metabolism, Brown Fat Thermogenesis.
Why does Mitochondrial Dynamics matter?
Dynamics adapt energy supply to need.
Can you give an example of Mitochondrial Dynamics?
Exercise stimulates mitochondrial biogenesis through PGC-1α.
What should I learn before Mitochondrial Dynamics?
Work through the Beginner topics in Metabolism & Bioenergetics first, such as Metabolism, Anabolism and Catabolism, ATP, then return to Mitochondrial Dynamics. Advanced topics assume the Intermediate vocabulary.
What topics are related to Mitochondrial Dynamics?
The closest topics to Mitochondrial Dynamics are Proton Motive Force, Metabolism, Brown Fat Thermogenesis, AMPK and mTOR Signalling. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Mitochondrial Dynamics?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Mitochondrial Dynamics. To practise the whole of Metabolism & Bioenergetics, use the Metabolism & Bioenergetics quiz.
How is Mitochondrial Dynamics different from Proton Motive Force?
Mitochondrial Dynamics: Fusion, fission and mitophagy keep the mitochondrial population healthy. Proton Motive Force: The combined chemical and electrical gradient of protons that powers ATP synthase and transport. Read both side by side and note what each one explains.
How should I study Mitochondrial Dynamics step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Proton Motive Force and explain the difference aloud. Finally, take the Metabolism & Bioenergetics quiz and come back to this page for any question you miss.