Expression of a fungal lectin in Arabidopsis enhances plant growth and resistance towards microbial pathogens and plant-parasitic nematode

Abstract

Coprinopsis cinerea lectin 2 (CCL2) is a fucoside-binding lectin from the basidiomycete C. cinerea that is toxic to the bacterivorous nematode Caenorhabditis elegans as well as animal-parasitic and fungivorous nematodes. We expressed CCL2 in Arabidopsis to assess its protective potential towards plant-parasitic nematodes. Our results demonstrate that expression of CCL2 enhances host resistance against the cyst nematode Heterodera schachtii. Surprisingly, CCL2-expressing plants were also more resistant to fungal pathogens including Botrytis cinerea, and the phytopathogenic bacterium Pseudomonas syringae. In addition, CCL2 expression positively affected plant growth indicating that CCL2 has the potential to improve two important agricultural parameters namely biomass production and general disease resistance. The mechanism of the CCL2-mediated enhancement of plant disease resistance depended on fucoside-binding by CCL2 as transgenic plants expressing a mutant version of CCL2 (Y92A), compromised in fucoside-binding, exhibited wild type disease susceptibility. The protective effect of CCL2 did not seem to be direct as the lectin showed no growth-inhibition towards B. cinerea in in vitro assays. We detected, however, a significantly enhanced transcriptional induction of plant defense genes in CCL2- but not CCL2-Y92A-expressing lines in response to infection with B. cinerea compared to wild type plants. This study demonstrates a potential of fungal defense lectins in plant protection beyond their use as toxins.

Sweet Modifications Modulate Plant Development

“…Such interplay between sugar signaling events (translating the cellular energy levels) and glycosylation might be important to balance the rate of glycosylation with the current sugar status. Another interesting study showed that expression of the Coprinopsis cinerea lectin 2 (CCL2), a fucoside-binding lectin from Botrytis cinerea in Arabidopsis, enhanced growth and disease resistance against a variety of pathogens [465]. When the carbohydrate binding ability of CCL2 was disturbed, disease tolerance is abolished, suggesting that carbohydrate interaction is required for induced tolerance.…”