A transcription factor is
A) a subunit of RNA polymerase II that does not have a prokaryotic analogue.
B) the part of the promoter sequence closest to the start of transcription.
C) a protein other than RNA polymerase that is involved in transcription.
D) a sequence that determines whether an upstream element will be an enhancer or silencer.

Question

Quizplus · Accepted Answer

Transcription factors are proteins that bind to specific DNA sequences to control the flow (or transcription) of genetic information from DNA to mRNA. They are distinct from RNA polymerase, which is the enzyme directly responsible for the synthesis of RNA from a DNA template. Transcription factors can act as activators or repressors of transcription, thereby playing critical roles in regulating gene expression. Choices A, B, and D describe other components or aspects of gene regulation but do not accurately define transcription factors.

A Transcription Factor Is