Question

RNA polymerase has two binding sites for ribonucleotide triphosphates. The initiation site has a greater affinity for NTPs than the elongation site. What possible significance does this hold?

A) Faster initiation process
B) Increased transcription rate
C) Specificity in the elongation process
D) Reduced error rate in elongation

Answer 1

The higher affinity of the initiation site of RNA polymerase for NTPs contributes to c) specificity and potentially reduced error rate in elongation by ensuring correct positioning and efficient start of RNA synthesis.

Step-by-step explanation:

The question relates to the mechanism of transcription, particularly the significance of RNA polymerase having two binding sites for ribonucleotide triphosphates (NTPs): the initiation site and the elongation site.

RNA polymerases use NTPs to synthesize RNA and do not require a primer. The initiation site, with a higher affinity for NTPs, ensures the efficient and accurate start of RNA synthesis.

This can significantly affect thec) specificity in the elongation process because a strong initiation ensures that the RNA polymerase is correctly positioned on the DNA template for the accurate and efficient addition of ribonucleotides during the subsequent elongation phase.

Thus, the high affinity of the initiation site may contribute to a reduced error rate in elongation, although it may not directly influence the transcription rate or the speed of the initiation process itself.