Suppose that a portion of double-stranded DNA in the middle of a large gene is being transcribed by an RNA polymerase. As the polymerase moves through the sequence of six bases shown in the diagram below, what is the corresponding sequence of bases in the RNA that is produced?

Question

A portion of a double-stranded DNA. CCGAGT are located on the coding strand, from the 3 prime end to the 5 prime end. GGCTCA are located on the template strand from the 5 prime end to the 3 prime end.

Enter the sequence of bases as capital letters with no spaces and no punctuation. Begin with the first base added to the growing RNA strand, and end with the last base added.
View Available Hint(s)for Part A

Answer 1

To determine the RNA sequence that corresponds to the given DNA coding strand (CCGAGT) and template strand (GGCTCA), we need to follow the rules of transcription. RNA is synthesized by using the DNA template strand, replacing thymine (T) with uracil (U).

1. The DNA coding strand (the one that is identical to the RNA) is 5' CCGAGT 3'.
2. The template strand is complementary, so its sequence is 3' GGCTCA 5'.
3. RNA polymerase reads the template strand from 3' to 5' and synthesizes the RNA strand from 5' to 3'.

Based on the template strand (3' GGCTCA 5'), the RNA sequence synthesized will be complementary to that strand:

• G (from template) pairs with C (in RNA)
• G pairs with C
• C pairs with G
• T pairs with A (replace T with U in RNA)
• C pairs with G
• A pairs with U

Thus, the resulting RNA sequence synthesized will be:

CCGUGA

Therefore, the RNA sequence produced is CCGUGA.