Lon protease

[2020-06-13]

Talk by Kelvin J.A. Davies on Lon protease from 2013(?)


12:56 Degradation of oxidized proteins by proteasome is mostly ATP independent; degradation by Lon is ATP dependent 
20:08 the most decreased mRNA in skeletal muscle in mice in aging is Lon
20:36 the main one that comes up is aconitase, but there are many, many others 
20:17 Lon inducibility is diminished in senescent cells & they have more carbonylated proteins 
22:20 slide - Aging Decreases Lon Induction and Stress Protection
26:28 Lon attaches to mtDNA and allows for biogenesis; under stress it detaches and degrades oxidized proteins and at that point proliferation stops 
28:59 Lon is inducible by H2O2, heat stress, starvation, cold stress, mechanical shear stress, peroxynitrite


Also, loss of frataxin upregulates Lon and ClpP proteases and results in too much degradation of Fe-S proteins [1].


1 - Guillon, Blanche, Anne-Laure Bulteau, Marie Wattenhofer-Donzé, Stéphane Schmucker, Bertrand Friguet, Hélène Puccio, Jean-Claude Drapier, and Cécile Bouton. “Frataxin Deficiency Causes Upregulation of Mitochondrial Lon and ClpP Proteases and Severe Loss of Mitochondrial Fe-S Proteins.” The FEBS Journal 276, no. 4 (February 2009): 1036–47. https://doi.org/10.1111/j.1742-4658.2008.06847.x.

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