An in vitro transcription system that contains a bacterial gene initiates transcription but from random points on the DNA.Which of the following proteins MOST likely is missing from the reaction?
A)Sigma factor
B)Rho factor
C)RNA polymerase II
D)TATA-binding protein (TBP)
E)TFIID

Question

Quizplus · Accepted Answer

Sigma factors are subunits of bacterial RNA polymerase that bind to specific DNA sequences, known as promoters, and facilitate the initiation of transcription from a defined start site. Without sigma factor, RNA polymerase cannot properly initiate transcription at the correct location on the DNA, leading to transcription starting from random points. Rho factor is involved in transcription termination in bacteria, while RNA polymerase II, TBP and TFIID are components of the eukaryotic transcription machinery and do not play a role in prokaryotic transcription.

An in Vitro Transcription System That Contains a Bacterial Gene