Before revision: Since sgRNAs are usually expressed by RNA polymerase III, which limits the length of the RNA domain that can be inserted, CRISPR-Display incorporates RNA polymerase II to permit expression of longer transcripts (~ 80-250 nucleotides) to overcome this limitation.
After revision: Since sgRNAs are usually expressed by RNA polymerase III, which limits the length of the RNA domain that can be inserted, CRISPR-Display incorporates RNA polymerase II to permit expression of longer transcripts (~ 80–250 nucleotides) to overcome this limitation.