Amino Acid Starvation Has Opposite Effects on Mitochondrial and Cytosolic Protein Synthesis
Mark A. Johnson
Sara Vidoni
Romina Durigon
Sarah F. Pearce
Joanna Rorbach
Jiuya He
Gloria Brea-Calvo
Michal Minczuk
Aurelio Reyes
Ian J. Holt
Antonella Spinazzola
10.1371/journal.pone.0093597
https://plos.figshare.com/articles/dataset/_Amino_Acid_Starvation_Has_Opposite_Effects_on_Mitochondrial_and_Cytosolic_Protein_Synthesis_/993471
<div><p>Amino acids are essential for cell growth and proliferation for they can serve as precursors of protein synthesis, be remodelled for nucleotide and fat biosynthesis, or be burnt as fuel. Mitochondria are energy producing organelles that additionally play a central role in amino acid homeostasis. One might expect mitochondrial metabolism to be geared towards the production and preservation of amino acids when cells are deprived of an exogenous supply. On the contrary, we find that human cells respond to amino acid starvation by <i>upregulating</i> the amino acid-consuming processes of respiration, protein synthesis, and amino acid catabolism in the mitochondria. The increased utilization of these nutrients in the organelle is not driven primarily by energy demand, as it occurs when glucose is plentiful. Instead it is proposed that the changes in the mitochondrial metabolism complement the repression of cytosolic protein synthesis to restrict cell growth and proliferation when amino acids are limiting. Therefore, stimulating mitochondrial function might offer a means of inhibiting nutrient-demanding anabolism that drives cellular proliferation.</p></div>
2014-04-09 03:36:24
Biochemistry
Bioenergetics
Energy-producing organelles
enzymology
enzymes
metabolism
Carbohydrate metabolism
proteins
amino acids
protein synthesis
Nucleic acids
cell biology
Cellular structures and organelles
Molecular cell biology
Metabolic disorders
chemistry
Chemical compounds
acids
organic acids
organic chemistry
starvation
mitochondrial
cytosolic