Question

Which of the following is NOT an example of how regulatory transcription factors can be modulated?

		The vitamin D receptor regulates gene expression when bound to vitamin D.
		The glucocorticoid receptor binds to the GRE as a dimer.
		All of the answers are correct.
		ARX homeobox transcription factor in humans regulates gene expression after it is phosphorylated.
		The Bicoid transcription factor is only expressed during embryogenesis in Drosophila.

Answer 1

Answer :

The flow of genetic information takes the path, DNA-->RNA-->protein.

The process of making RNA from DNA is called transcription, and is the stage for most regulations in genegene expression.

Transcription factors must be regulated so that they do not bind and activate expression of proteins unnecessarily. To do this, various mechanisms are employed to conserve energy.

Transcription factors (TF) can be regulated by (1) controlling the expression of TF or by (2) modifications required to activate a TF after it has been expressed.

Out of the given examples, vitamin D receptor, glucocorticoid receptor, ARX homeobox are transcription factors which are being modulated (modified) for their activation.

On the other hand, transcription of bicoid transcription factor is itself controlled and after it doesn't involve modulation.

Hence, the correct choice for NOT an example of how regulatory transcription factors can be modulated should be:

The Bicoid transcription factor is only expressed during embryogenesis in Drosophila.