Inhibitory effect of esterified lactoferin and lactoferin against tobacco mosaic virus (TMV) in tobacco seedlings

The inhibitory effects of esterified lactoferrin (ELF) and lactoferrin (LF) against tobacco mosaic virus (TMV) in tobacco seedlings and the underlying mechanism were investigated. ELF and LF significantly inhibited viral infection and TMV multiplication in tobacco plants. ELF showed a higher inhibition effect against TMV than LF treatment in a dose and time-dependent way. Moreover, ELF induced a higher increase in the levels of transcription of pathogenesis-related (PR) protein genes [acidic PRs (PR-1a, PR-2, PR-3, PR-5) and basic PR-1] and defense-related enzymes [phenylalanine ammonia lyase (PAL, EC 4.3.1.5), and 5-epi-aristolochene synthase (EAS, EC 2.5.1.35)] both locally and systemically, in correlation with the induction of resistance against tobacco mosaic virus. Furthermore, ELF also induced accumulation of salicylic acid, SA 2-O-β-d-glucoside and H2O2. These results suggested that ELF and LF could control TMV incidence and the mechanism might attribute to activate the expression of a number of defense genes.

Both esterified lactoferrin (ELF) and lactoferrin (LF) strongly inhibited the infection of tobacco mosaic virus (TMV) in tobacco seedlings.Figure optionsDownload as PowerPoint slideHighlights
► Esterified lactoferin and lactoferin provide an effective control of TMV.
► The mechanism might be attributed to affect the early phase of infection and prevent the entry of virus into the host cell.
► The inhibitory effects also may be associated with the expression of a number of defense genes.