Gravitational and mechanical forces shape mitochondrial translation 2026 Wakigawa et al

[Andy]

Abstract​

Life on Earth has evolved in a form suitable for the gravitational force. Although the pivotal role of gravity in gene expression has been suggested, the molecular details remain unclear. Here, we show that mitochondria utilize gravity to activate protein synthesis within the organelle. Genome-wide ribosome profiling reveals reduced mitochondrial translation in mammalian cells and Caenorhabditis elegans under microgravity.

We found that attenuation of cell adhesion through laminin–integrin interactions caused the phenotype. Mitochondrial translation is activated by a signal relayed by FAK, RAC1, PAK1, BAD, and Bcl-2 family proteins in the cytosol, and the mitochondrial fatty acid synthesis (mtFAS) pathway in the matrix. Consumption of mitochondrial malonyl-CoA by mtFAS reduces the malonylation of the translational machinery and accelerates the rates of translational initiation and elongation. Physiologically, this system operates in mechano-response of skeletal muscles. Our work provides mechanistic insights into how cells convert gravitational and mechanical forces into translation in mitochondria.

Open access

 

[Creekside]

The details of the study are beyond my ME brain capacity, but there seem to be a lot of assumptions in the study; interpretations rather than direct observations. Given how small the gravitational force would be on molecules in mitochondria, I think it's more likely that any changes observed are due to the forces from the fluids around the mitochondria. The apparatus might even be inducing localized electrical charges that would overwhelm gravitational force. Any study that's measuring extremely small forces faces that problem.

 

[Jonathan Edwards]

I agree. Years ago I expressed caution to those studying hydrostatic pressure effects on chondrocytes in vitro - popular at the time. A good while later someone thanked me for having saved them waste another five years.