Question

Is the binding of a transcription factor to its DNA recognition sequence necessary and sufficient for an initiation of transcription at a regulated gene?

a) Transcription factors are proteins that are necessary for the initiation of transcription. They are sufficient for the initiation of transcription.
b) Transcription factors are proteins that are not necessary for the initiation of transcription.
c) Transcription factors are proteins that are necessary for the initiation of transcription. However, they are not sufficient for the initiation of transcription.

Answer 1

Transcription factors are necessary but not sufficient for the initiation of transcription at a regulated gene. They bind to specific DNA recognition sequences and work in conjunction with other regulatory elements to initiate transcription.

Step-by-step explanation:

Transcription factors are proteins that are necessary for the initiation of transcription at a regulated gene. However, they are not sufficient for the initiation of transcription on their own. Transcription factors bind to specific DNA recognition sequences called cis-acting elements, which are located just upstream of the gene's promoter region. These cis-acting elements interact with other regulatory elements, such as enhancers, to facilitate the initiation of transcription.