ARCA

A critical step in mRNA processing is the addition of a 5’ cap structure, a 5'-5' triphosphate linkage between the 5' initiating terminal of the RNA and a guanosine nucleotide. The cap is then methylated enzymatically at the N-7 position of the guanosine to form a mature mCAP.

And now, Anti Reverse Cap Analog (ARCA) is introduced. ARCA with the ability only inserting in the proper orientation, results in forming mRNAs that can be translated twice efficiently as those initiated with mCAP.

When preparing synthetic mRNA, the cap is often added prior to use in order to stabilize the mRNA and significantly enhance translation. Using a 4:1 mixture of a cap analog to GTP in transcription reactions will cap 80% of the resulting mRNAs.

References:
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