100 Turns a Second: The Spinning Motor Inside Your Mitochondria

Between one and a half and two billion years ago, a bacterium ended up inside another cell. Instead of being digested, it stayed, and its descendants are powering you right now. The origin story of mitochondria: the real human ATP synthase spinning in its membrane, the 37-gene DNA ring they still carry, Lynn Margulis's idea that was turned down by about fifteen journals, the clues that proved her right, the Asgard-like microbe that was probably the host, and why your mitochondrial DNA comes from your mother. 3D models are simplified illustrations and may not be exact. Models: "Human Cell" by Shihab, "Mitochondria" by CAPTAAINRO and "Bacterium" by andrewfrueh (Sketchfab, CC BY 4.0, recoloured); ATP synthase built from Protein Data Bank entry 8H9S and ATP from PubChem 5957; the DNA ring and the Asgard-like archaeon are our own builds. Chapters 0:00 Something that used to be a bacterium 0:13 Mitochondria: a thousand in one liver cell 0:25 What they do with your oxygen 0:37 ATP synthase, the spinning motor 0:53 Your body weight in ATP, every day 1:07 Their own DNA: 16,569 letters, 37 genes 1:24 Lynn Margulis, 1967 1:42 Four clues 1:58 The genes settle it 2:13 1.5 to 2 billion years ago 2:29 The host: an Asgard archaeon 2:46 Two partners become one cell 3:00 Only 13 proteins still made at home 3:14 From your mother 3:31 What we still don't know Sources Sagan (Margulis) 1967, Journal of Theoretical Biology: https://doi.org/10.1016/0022-5193(67)90079-3 Anderson et al. 1981, Nature (the human mitochondrial genome): https://doi.org/10.1038/290457a0 Rath et al. 2021, Nucleic Acids Research (MitoCarta3.0): https://doi.org/10.1093/nar/gkaa1011 Lai et al. 2023, Molecular Cell (human ATP synthase, PDB 8H9S): https://doi.org/10.1016/j.molcel.2023.04.029 Imachi et al. 2020, Nature (the Asgard archaeon grown in the lab): https://doi.org/10.1038/s41586-019-1916-6 Rojansky, Cha & Chan 2016, eLife (paternal mitochondria eliminated): https://doi.org/10.7554/eLife.17896 Credits "Human Cell" by Shihab (Sketchfab, CC BY 4.0), recoloured "Mitochondria" by CAPTAAINRO (Sketchfab, CC BY 4.0), recoloured "Bacterium" by andrewfrueh (Sketchfab, CC BY 4.0), recoloured ATP synthase: Protein Data Bank 8H9S (Lai et al. 2023); ATP: PubChem CID 5957 DNA ring and Asgard-like archaeon: Cellula Magna's own 3D builds Subscribe to Cellula Magna, and stay curious. #mitochondria #biology #evolution