Before revision: In the biological context of organisms' production of gene products, downregulation is the process by which a cell decreases the quantity of a cellular component , such as RNA or protein , in response to an external stimulus.
After revision: In the biological context of organisms' production of gene products, downregulation is the process by which a cell decreases the production and quantities of its cellular components , such as RNA and proteinsbiochemistry, inregulation of gene expression and , in response to an external stimulus.