Protein–protein interaction
Regulation
Regulation
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* Protein concentration, which in turn are affected by expression levels and degradation rates;
* Protein affinity for proteins or other binding ligands;
* Ligands concentrations ([substrates](/wiki/Substrate_%28biochemistry%29 "Substrate (biochemistry)"), [ions](/wiki/Ions "Ions"), etc.);
* Presence of other [proteins](/wiki/Proteins "Proteins"), [nucleic acids](/wiki/Nucleic_acids "Nucleic acids"), and [ions](/wiki/Ions "Ions");
* [Electric fields](/wiki/Electric_field "Electric field") around proteins.
* Occurrence of covalent modifications;

What factors affect protein concentration?