Component of the protein complex eIF4F, which is involved in the recognition of the mRNA cap, ATP-dependent unwinding of 5'-terminal secondary structure and recruitment of mRNA to the ribosome (By similarity). Recognizes and binds the 7-methylguanosine-containing mRNA cap during an early step in the initiation of protein synthesis and facilitates ribosome binding by inducing the unwinding of the mRNAs secondary structures (By similarity). Key component of recessive resistance to potyviruses (PubMed:27655175, PubMed:22242134, PubMed:26850324). (Microbial infection) Susceptibility host factor required for viral infection (e.g. potato virus Y (PVY) and tobacco etch virus (TEV)) by recruiting viral RNAs to the host ribosomal complex via an interaction with viral genome-linked protein (VPg). EIF4F is a multi-subunit complex, the composition of which varies with external and internal environmental conditions (By similarity). It is composed of at least EIF4A, EIF4E and EIF4G. EIF4E is also known to interact with other partners (By similarity). In higher plants two isoforms of EIF4F have been identified, named isoform EIF4F and isoform EIF(iso)4F (By similarity). Isoform EIF4F has subunits p220 and p26, whereas isoform EIF(iso)4F has subunits p82 and p28 (By similarity). (Microbial infection) Interacts with potyvirus viral genome-linked protein (VPg) in the nucleus; mostly potato virus Y (PVY-LYE84) and tobacco etch virus (TEV-HAT) VPg, but not with PVY-LYE90 and pepper mottle virus (PepMoV) VPg; these interactions are possible in susceptible hosts but impaired in resistant plants. According to the redox status, the Cys-119-Cys-157 disulfide bridge may have a role in regulating protein function by affecting its ability to bind capped mRNA. Slightly impaired growth and fertility (PubMed:22242134). Plants lacking both eIF4E1 and eIF4E2 display pleiotropic effect on plant development but are resistant specifically to several potyviruses including potato virus Y (PVY, strains N605, LYE72, LYE90 and LYE84), tobacco etch virus (TEV, strains HAT, CAA10 and S103), pepper mottle virus (PepMoV), Ecuadorian rocotto virus (ERV), pepper severe mosaic virus (PepSMV), pepper yellow mosaic virus (PepYMV), and potato virus V (PVV) (PubMed:27655175, PubMed:22242134, PubMed:26850324). Plants lacking eIFiso4E, eIF4E1 and eIF4E2 exhibit a semi-dwarf phenotype (PubMed:22242134). Belongs to the eukaryotic initiation factor 4E family.