RNA Cap Analog Selection Chart

The 5′ terminal m7G cap present on eukaryotic mRNA is required for efficient translation. In addition, the cap structure allows for a regulated degradation of mRNA via multiple decapping-exonuclease degradation pathways (1) In vitro transcripts with 5′ terminal cap structures can be translated efficiently as eukaryotic mRNA in a eukaryotic cell-free protein synthesizing system. The 5′ cap structure can be added post-transcriptionally by using vaccinia capping enzyme (NEB #M2080) or co-transcriptionally using cap analogs. The use of cap analogs allows one to add non-conical cap structures to the in vitro transcription, with a trade of lower transcript yield (due to the lower GTP concentration used in transcription) and incomplete capping (due to the competition of GTP with the cap analog for the initiation nucleotide).

1. Garneau NL, et al (2007). Nature Reviews Molecular Cell Biology. 8, 113–126

PRODUCT APPLICATIONS
Anti-Reverse Cap Analog (ARCA)
3′-O-Me-m7G(5′) ppp(5′)G
Produces 100% translatable capped transcripts
Co-transcriptional capping with T7 (NEB #M0251), SP6 (NEB #M0207) and T3 RNA polymerases
Synthesis of m7G capped RNA for in vitro splicing assays
Synthesis of m7G capped RNA for transfection or microinjection
Standard Cap Analog
m7G(5′)ppp(5′)G
Co-transcriptional capping with T7, SP6 and T3 RNA polymerases
Synthesis of m7G capped RNA for in vitro splicing assays
Synthesis of m7G capped RNA for transfection or microinjection
Unmethylated Cap Analog
G (5′)ppp(5′)G
Co-transcriptional capping with T7, SP6 and T3 RNA polymerases
Synthesis of unmethylated G capped RNA
Methylated Cap Analog for A+1 sites
m7G(5′)ppp(5′)A
Co-transcriptional capping with T7 RNA polymerase from the phi2.5 promoter that contains an A at the transcription initiation site
Synthesis of m7G capped RNA for in vitro splicing assays
Synthesis of m7G capped RNA for transfection or microinjection
Unmethylated Cap Analog for A+1 sites
G(5′)ppp(5′)A
Co-transcriptional capping with T7 RNA polymerase from the phi2.5 promoter that contains an A at the transcription initiation site
Synthesis of unmethylated G capped RNA
Synthesis of A capped RNA