Fig. 5.

Commercialization and commonly used Cap. The 5′ cap of mRNA is critical to improve mRNA stability and promote translation efficiency. Modification of the 5′-5′ phosphate bridge can increase the resistance to DcpS and Dcp1/Dcp2, but the translation efficiency may not necessarily increase (such as the introduction of methylene groups on the phosphate bridge). The modification of ribose nucleosides also plays essential functions in mRNA translation by recruiting translation initiation factors, such as the methylation modification on the N7 position of the guanosine cap and the ribose-2′O position of the first nucleotide (Cap 1), increasing the affinity for eIF4E and thereby improving translation efficiency^116,539