Increased pathogen resistance and yield in transgenic plants expressing combinations of the modified antimicrobial peptides based on indolicidin and magainin

Abstract

Reverse peptide of indolicidin (Rev4), a 13-residue peptide based on the sequence of indolicidin, has been shown to possess both strong antimicrobial and protease inhibitory activities in vitro. To evaluate its efficacy in vivo, we produced and evaluated transgenic tobacco (Nicotiana tabacum L.) and Arabidopsis thaliana [(L.) Heynh.] plants expressing Rev4 with different signal peptide sequences for pathogen resistance. All transgenic plants showed normal growth and development, an indication of no or low cytotoxicity of the peptide. Furthermore, the transgenic plants exhibited elevated resistance to three bacterial and two oomycete pathogens. Interestingly, tobacco plants expressing Rev4 displayed enhanced yield compared to the control as indicated by an increased biomass production by as much as 34% in two field trials. When Rev4 was coexpressed with another antimicrobial peptide, Myp30, the disease resistance levels in the transgenic Arabidopsis were enhanced. These findings suggest the potential of using these peptides to protect plants from microbial pathogens and to enhance yield.

Inhibition of Fungal and Bacterial Plant Pathogens In Vitro and In Planta with Ultrashort Cationic Lipopeptides

“…One of the most ancient and widespread defense strategies involves the production of cysteine-rich antimicrobial peptides (AMPs) composed of 45 to 54 amino acids (13,14,20,37,57). AMPs have been shown to be produced by a wide range of organisms and serve as their natural defense against infection (60,61). Moreover, plant AMPs show structural and functional homology to their counterparts in animals, insects, and mammalian AMPs (8), whose involvement in host defense is well established (23,46,61).…”

Antifungal Activity of (KW)n or (RW)n Peptide against Fusarium solani and Fusarium oxysporum

“…At present, the high cost of synthetic peptides constitutes an obvious limitation to agricultural and food applications. As a result, there have been many efforts to express short AMPs in transgenic plants [38,39], for example indolicidin [40,41]. Short hexapeptides are used to control postharvest diseases in fruits and vegetables caused by fungal phytopathogens [21,23,42].…”

Antimicrobial peptides

“…114 Consistently, concomitant expression of AMPs in plants usually leads to higher levels of induced resistance than their individual expression. 115,116 This finding is reminiscing of the effect known from combining disease resistance genes (gene pyramiding) in traditional breeding, which often results in long-lasting, durable plant protection against pathogens.…”