What is gene down-regulation?
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.
How do you explain down-regulation?
Downregulation: An decrease in the number of receptors on the surface of target cells, making the cells less sensitive to a hormone or another agent. For example, insulin receptors may be downregulated in type 2 diabetes.
What is an example of downregulation?
An example of downregulation is the cellular decrease in the number of receptors to a molecule, such as a hormone or neurotransmitter, which reduces the cell’s sensitivity to the molecule. This phenomenon is an example of a locally acting negative feedback mechanism.
What is up and down-regulation of receptors?
In up-regulation, the number of receptors increases in response to rising hormone levels, making the cell more sensitive to the hormone and allowing for more cellular activity. When the number of receptors decreases in response to rising hormone levels, called down-regulation, cellular activity is reduced.
What causes down regulation of gene expression?
Modification of DNA In eukaryotes, the accessibility of large regions of DNA can depend on its chromatin structure, which can be altered as a result of histone modifications directed by DNA methylation, ncRNA, or DNA-binding protein. Hence these modifications may up or down regulate the expression of a gene.
What is down regulation receptor?
Receptor downregulation is characterized by a decrease in total receptor number in the cell due to endocytosis and subsequent degradation of the receptors caused by long-term exposure to agonists (see Fig.
What causes down regulation?
Downregulation (i.e., decrease in number) is the inverse of upregulation. It occurs due to repeated or long-term administration of an agonist. Along with downregulation, desensitization of the receptor to the drug may also occur.
What is down regulation quizlet?
Down-regulation. prolonged exposure to high hormone concentrations can decrease the # of receptors of that hormone; desensitizes the target cells, so they response less vigoursly to hormonal stimulation, preventing them from overreacting to persistently high hormone levels.
Why does down regulation occur?
What is the difference between down-regulation and up-regulation quizlet?
So a decrease in the number of receptors to a message sited on the cell membrane reduces the cell’s sensitivity to the message. That’s called down-regulation. Similarly if the cell receives a weak signal, it can up-regulate by pumping out more receptors such as to increase the sensitivity to the weak message.