Does it matter which strand is the 'code strand'? The following two sequences look identical, except one runs 3'-5' and the other 5'-3'. For each DNA sequence given below, write the mRNA sequence that would be coded from it. Make sure you indicate the direction of each mRNA strand (i.e. 3' and 5' ends).

Question

a. DNA 3'-TACCTACTTTGCCCGATCCAT-5'
mRNA

b. DNA 5'-TACCTACTTTGCCCGATCCAT-3'
mRNA

Answer 1

A - 5-3
UACCUACUUUGCGCGTAUCCAT
B - 3-5
UACCUACUUUGCCCGAUCCAU