From DNA to mRNA: Transcription
Transcription is the first step of gene expression, where a specific segment of DNA is copied into RNA (specifically, messenger RNA or mRNA) by the enzyme RNA polymerase. During this process, the DNA base Thymine (T) is inherently replaced by Uracil (U) in the RNA product.
Coding strand vs. Template strand
In a double-stranded DNA molecule, only one strand is actually used by the RNA polymerase as a physical template to build the mRNA. This is called the Template Strand (or Antisense strand). The newly generated mRNA is exactly complementary to this strand.
Because of DNA's double-helix complementary pairing, the other strand—the Coding Strand (or Sense strand)—ends up having almost the exact same sequence as the final mRNA, with the only difference being that all the T's are swapped with U's.
How to use this converter
This simple tool will instantaneously compute the resulting mRNA sequence for you:
- Select your strand type: Choose whether you are pasting the sequence of the coding block, or the template block.
- Paste the sequence: Note that invalid characters (anything other than A, T, C, or G) will throw an error. The tool will ignore blank spaces.
- For coding strands, the sequence is mapped T → U.
- For template strands, typical Watson-Crick pairings are made (but A maps to U). We assume template input is read natively 3'→5', generating standard 5'→3' mRNA.