Question

Compare and contrast how activators, coactivators, repressors, TFIID, and mediator play a role in gene regulation. Could you clarify this process.

Answer 1

Gene regulation is the process  used by a cell to increase or decrease the production of specific gene products (protein or RNA) or controlling which genes in a cell's DNA are expressed. Different cells in a multicellular organism may express very different sets of genes, even though they contain the same DNA.There are 3 steps involved in gene regulation.They are Transcription, translation and post translation.

There are various factors that helps gene regulation transcription.They are activators ,Coactivators,Repressors,TFIID and Mediators.

Comparison.

Activator	Coactivator	Repressor	TFIID	Mediator
It has single DNA binding protein.It stimulates the transcription of gene regulation.Enhances RNA polymerase binding.Helps to mitigate the damge to cells.	It is protein that binds to activator.This also helps to increase the speed of transcription.Helps to restore cell damage.	These are DNA or RNA binding protein.It is a negatively acting regulatory protein.It can inhibit the transcription.	It is a complex of protein that first binds to DNA during the formation of the pre initiation transcription complex of RNA polymerase.	It is multi protein complex that transmits signals from transcription factors to the polymerase.Controls the expression of certain genes.

Contrast

Activator	Coactivator	Repressor	TFIID	Mediator
Found in all living organisms>Single DNA binding protein	Found in Eukaryotes.Complex protein structure	In contrast to activators and coactivators they inhibit transcription.	This protein works before transcription. It binds to core promoter of the gene before transcription	Found in Eukaryotes and its sequences and subparts found in humans.Controls during pre initiation of transcription