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Updated: Jun 5, 2026
Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils
Published on: September 28, 2019
[Protein synthesis and characterization in isolated mitochondria from rat brain]
Ming-Chun Cai1, Jun-Ze Liu, Li-Ping Wu
1Department of Pathophysiology,Third Military Medical University, Chongqing 400038, China.
Aim:
To establish a system of mitochondrial translation in vitro of rat brain and identify it's production of protein by molecular weight.
Methods:
Mitochondria isolated from hemisphere of rat brain by differential centrifugations. The optimization of mitochondrial translation in vitro by 3H-Lencine incorporation was explored. 35S-methionine labeled products of mitochondrial protein synthesis were identified by SDS-PAGE and fluorography.
Results:
Isolated mitochondria had a highly activity oxidative phosphorylation and respiratory control ratio (RCR) was between 3.5 and 5.5. The activity of 3H-Lencine incorporation in isolated mitochondria in vitro increased with time of incubation in 60 min and maintained a steady level. The maximal activity of 3H-Lencine incorporation per milligram mitochondria protein occured at 1 mg mitochondria/ml of incubation mix.The major auto radiographic bands could be observed at 86, 68, 56, 43, 33, 29, 25 and 18(kD) molecular weight separated on SDS-PAGE.
Conclusion:
The translation system of rat brain mitochondria in vitro is faithful and high activity, can be used to study mtDNA expression and regulation in mammalian brain at the level of translation.
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