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N-terminal epitope tag - keep or remove ORF start codon - (Jan/13/2014 )

When adding an epitope tag to the N-terminus, should I keep the ORF's start codon or remove it? Obviously the true start codon will be before the epitope tag. I didn't know if removing it would cause issues or if it really doesn't matter either way. 

 

Thanks!

-Epigeneticist-

In theory you should remove it, so as to prevent ribosome skipping, but this is only the case for very short tags.  In practice I generally keep the initial ATG in my sequences, and haven't observed any problems.

-bob1-