A. In vitro transcription reactions were performed using a DNA template containi
ID: 41192 • Letter: A
Question
A. In vitro transcription reactions were performed using a DNA template containing a Rho independent
terminator and wild type (RpoB+) or rpoB8 mutant RNA pol. The length of the RNA transcript will be
approximately 6100 nt when RNA polymerase encounters the terminator.
- How long does it take until the wild type and rpoB8 polymerases to reach the terminator?
- What is the elongation rate of the wild type and rpboB8 polymerases? Show your calculation in nt/sec.
- Explain which polymerase terminates more efficiently.
Explanation / Answer
it takes 35 mins for the wild type to reach the terminator and 40 mins for mutant to reach terminator.
-
the wild type polymerase terminates more efficiently as compared to the mutant, because the exit channel of the mRNA from the RNA polymerase is blocked by the rpoB8 mutation.