Chapter 22, Problem 22.82EP

(a)

Interpretation Introduction

Interpretation: The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ TAAT $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction has to be predicted.

Concept introduction: DNA strand contains a complementary base pairing between A-T and C-G.  The complementary strands are antiparallel to each other.  RNA molecule contains the similar base pairing but the base thymine is replaced by uracil.

Answer to Problem 22.82EP

The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ TAAT $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction is $5\text{'}$ AUUA $3\text{'}$.

Explanation of Solution

The given DNA template strand is $5\text{'}$ TAAT $3\text{'}$.  Its corresponding informational DNA strand is $3\text{'}$ ATTA $5\text{'}$.  Reading the informational DNA strand in $5\text{'}$-to-$3\text{'}$ direction, it is $5\text{'}$ ATTA $3\text{'}$.  In RNA molecule, thymine is replaced by uracil.  Therefore, the base coding for initially synthesized RNA is $5\text{'}$ AUUA $3\text{'}$.

(b)

Interpretation Introduction

Interpretation: The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ CGCG $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction has to be predicted.

Concept introduction: DNA strand contains a complementary base pairing between A-T and C-G.  The complementary strands are antiparallel to each other.  RNA molecule contains the similar base pairing but the base thymine is replaced by uracil.

Answer to Problem 22.82EP

The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ CGCG $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction is $5\text{'}$ CGCG $3\text{'}$.

Explanation of Solution

The given DNA template strand is $5\text{'}$ CGCG $3\text{'}$.  Its corresponding informational DNA strand is $3\text{'}$ GCGC $5\text{'}$.  Reading the informational DNA strand in $5\text{'}$-to-$3\text{'}$ direction, it is $5\text{'}$ CGCG $3\text{'}$.  Therefore, the base coding for initially synthesized RNA is $5\text{'}$ CGCG $3\text{'}$.

(c)

Interpretation Introduction

Interpretation: The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ TCAG $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction has to be predicted.

Concept introduction: DNA strand contains a complementary base pairing between A-T and C-G.  The complementary strands are antiparallel to each other.  RNA molecule contains the similar base pairing but the base thymine is replaced by uracil.

Answer to Problem 22.82EP

The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ TCAG $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction is $5\text{'}$ CUGA $3\text{'}$.

Explanation of Solution

The given DNA template strand is $5\text{'}$ TCAG $3\text{'}$.  Its corresponding informational DNA strand is $3\text{'}$ AGTC $5\text{'}$.  Reading the informational DNA strand in $5\text{'}$-to-$3\text{'}$ direction, it is $5\text{'}$ CTGA $3\text{'}$.  In RNA molecule, thymine is replaced by uracil.  Therefore, the base coding for initially synthesized RNA is $5\text{'}$ CUGA $3\text{'}$.

(d)

Interpretation Introduction

Interpretation: The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ TTTT $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction has to be predicted.

Concept introduction: DNA strand contains a complementary base pairing between A-T and C-G.  The complementary strands are antiparallel to each other.  RNA molecule contains the similar base pairing but the base thymine is replaced by uracil.

Answer to Problem 22.82EP

The base sequence for initially synthesized RNA for the DNA template strand $5\text{'}$ TTTT $3\text{'}$ in $5\text{'}$-to-$3\text{'}$ direction is $5\text{'}$ AAAA $3\text{'}$.

Explanation of Solution

The given DNA template strand is $5\text{'}$ TTTT $3\text{'}$.  Its corresponding informational DNA strand is $3\text{'}$ AAAA $5\text{'}$.  Reading the informational DNA strand in $5\text{'}$-to-$3\text{'}$ direction, it is $5\text{'}$ AAAA $3\text{'}$.  Therefore, the base coding for initially synthesized RNA is $5\text{'}$ AAAA $3\text{'}$.