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 (PubMed:20593023, PubMed:26850324). 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 (PubMed:26850324). Key component of recessive resistance to potyviruses (PubMed:15971038, PubMed:20593023, PubMed:27655175, PubMed:22242134, PubMed:26850324, PubMed:32849681). (Microbial infection) Susceptibility host factor required for viral infection (e.g. potato virus Y (PVY), pepper mottle virus (PepMoV) 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); mostly with tobacco etch virus (TEV-HAT) VPg and, to a lower extent, with potato virus Y (PVY-LYE84 and PVY-LYE90) and pepper mottle virus (PepMoV) VPg. According to the redox status, the Cys-129-Cys-167 disulfide bridge may have a role in regulating protein function by affecting its ability to bind capped mRNA. Variant present in the allele pot1(2), haplotypes 1 and 4, is associated with an increased resistance to potato virus Y (PVY) isolate N605. Variant present in the allele pot-1 is associated with a functionnal mRNA capping activity and normal susceptibility to potyviruses (e.g. pepper mottle virus (PepMoV), potato virus Y (PVY) and tobacco etch virus (TEV)). Impaired mRNA capping activity (PubMed:26850324). Slightly impaired growth and fertility (PubMed:22242134). Increased resistance to pepper mottle virus (PepMoV) and potato virus Y (PVY) strain LYE90 but not to PVY strains N605, LYE72, SON41 and LYE84 and to tobacco etch virus (TEV) strains HAT, CAA10 and S103 (PubMed:26850324). 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). Displayed sequence is cv. Mospomorist and cv. M82, and confers susceptibility to potyviruses (e.g. potato virus Y (PVY) and tobacco etch virus (TEV)). Belongs to the eukaryotic initiation factor 4E family.