Product Overview

Amino-hexynyl-pApG is a chemically synthesized capping initiator designed for site-specific 5′-end modification of mRNA during in vitro transcription (IVT). Upon incorporation at the 5′-end, this dinucleotide analog introduces a primary amine functional group, enabling bio-orthogonal labeling of capped mRNA through NHS ester-based conjugation.

While it does not serve as a traditional cap structure that promotes ribosome recruitment, Amino-hexynyl-pApG enhances mRNA stability and maintains a level of translation efficiency that is superior to uncapped RNA. It also functions as a versatile reporter, supporting a wide range of chemical modifications at the 5′-terminus.

Addressing a key limitation in mRNA labeling

Conventional mRNA modification strategies are predominantly focused on the 3′-end, where enzymatic addition of functional groups enables bioconjugation. However, targeted 5′-end modifications have remained limited due to the complexity of preserving cap structure and functionality.

Amino-hexynyl-pApG offers a direct and efficient solution for 5′-end functionalization of enzymatically capped mRNA without disrupting the transcript’s integrity, allowing for new experimental and therapeutic capabilities.

Benefits & Applications

• Introduces a primary amine at the mRNA 5′-end
• Enables site-specific labeling via NHS ester conjugation
• Compatible with enzymatically capped mRNA
• Useful in fluorescent tagging, surface immobilization, and targeted delivery
• Expands options for dual-end labeling (5′ and 3′)
• Supports development of RNA therapeutics, including cell-specific targeting

Use Cases

• Fluorescent and affinity labeling of synthetic mRNA for imaging and tracking
• Conjugation of peptides, ligands, nanoparticles, or biotin via NHS esters
• Engineering targeted mRNA constructs for delivery or replacement therapies
• Investigating mRNA structure–function relationships or RNA–protein interactions

Summary

Amino-hexynyl-pApG provides researchers with a powerful and flexible tool for site-selective modification of the mRNA 5′-end. By enabling primary amine-mediated conjugation through NHS ester chemistry, it unlocks new potential in mRNA labeling, imaging, and therapeutic development — complementing traditional 3′-modification strategies and advancing the field of synthetic RNA engineering.