In molecular biology, the 5′-cap structure of mRNA plays a central role in the stability of mRNA and in the initiation of translation traditional methods for synthesizing cap analogs are often labor-intensive, producing low yields and time-consuming. However, recent advances have introduced a new approach using click chemistry, specifically copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC), to produce phosphate-modified cap analogs.

This innovative method enables the efficient synthesis of 5′-cap mimics by combining two nucleotide units, resulting in a linear dinucleotide cap analog, with a free clickable moiety. Like our alkyne-C8-5′- phosphoadenylyl- (3′ −> 5′)- guanosine (pApG or 5′-p(rA)p(rG)). This enables you to produce easy different cap structures by clicking to conventional cap structures with corresponding azide modified nucleotide.

In addition, click labeling of mRNA at 5’-end with e.g. targeting agents, protective entities to prevent degradation, or fluorescent dyes. These cap analog not only increase mRNA stability but also improve translation efficiency, making them highly valuable for research and therapeutic applications, including RNA-based vaccines and gene replacement therapies.

Several cap analogs have been identified, when incorporated into mRNA, exhibit comparable translational efficiency after clicking to conventional cap structures. This breakthrough opens new possibilities for the development of chemically modified mRNAs that can be used in various biomedical applications, offering a promising future for mRNA-based treatments.

LITERATURE

A novel route for preparing 5′ cap mimics and capped RNAs: phosphate-modified cap analogues obtained via click chemistry, S. Walczak et al., 2017, Chemical Science, Vol. 8, p. 260-267

https://doi.org/10.1039/C6SC02437H