Characterization of the hypersensitive response‐like cell death phenomenon induced by targeting antiviral lectin griffithsin to the secretory pathway

Abstract

SummaryGriffithsin (GRFT) is an antiviral lectin, originally derived from a red alga, which is currently being investigated as a topical microbicide to prevent transmission of human immunodeficiency virus (HIV). Targeting GRFT to the apoplast for production in Nicotiana benthamiana resulted in necrotic symptoms associated with a hypersensitive response (HR)‐like cell death, accompanied by H2O2 generation and increased PR1 expression. Mannose‐binding lectins surfactant protein D (SP‐D), cyanovirin‐N (CV‐N) and human mannose‐binding lectin (hMBL) also induce salicylic acid (SA)‐dependent HR‐like cell death in N. benthamiana, and this effect is mediated by the lectin's glycan binding activity. We found that secreted GRFT interacts with an endogenous glycoprotein, α‐xylosidase (XYL1), which is involved in cell wall organization. The necrotic effect could be mitigated by overexpression of Arabidopsis XYL1, and by co‐expression of SA‐degrading enzyme NahG, providing strategies for enhancing expression of oligomannose‐binding lectins in plants.

Crosstalk between cytokinin and ethylene signaling pathways regulates leaf abscission in cotton in response to chemical defoliants

“…Polygalacturonase is thought to be important for pectin degradation during cell separation, and is expressed in the abscission zone ( Rhee and Somerville, 1998 ; Ogawa et al ., 2009 ). Xylosidase is involved in cell wall organization ( Kim et al ., 2018 ) and β-glucosidase also mediates hydrolysis of Glc-conjugated ABA (ABA-GE) to increase the level of ABA in Arabidopsis ( Xu et al ., 2012 ). Some oxidative stress-related peroxidase genes were preferentially expressed following TE treatment ( Supplementary Fig.…”

Comprehensive Analysis of Soybean Mosaic Virus P3 Protein Interactors and Hypersensitive Response-Like Lesion-Inducing Protein Function

“…The HRL gene has been reported to be an essential gene in pathogen infection progress, as the mutant plants showed necrotic lesions and embryonic lethal phenotype [46,47,48]. The produce of griffithsin (GRFT) in Nicotiana benthamiana leads to necrotic symptoms and HRLI cell death, with high expression of H 2 O 2 and PR1 [49]. During Oat dwarf virus (ODV) infection, the NbFDN1 is an important component induced by H 2 O 2 expression, resulting in HRLI cell death [50].…”

Phytohormonal cross-talk modulate Bipolaris sorokiniana (Scc.)interaction with Zea mays

“…Upon the plant microbe interaction, several hypersensitive reactions, including hormonal biosyntheses and the subsequent signal transduction mechanism are triggered (Kim et al, 2018). Such signal transduction in host later develops the expression of genes which decide the fate of microbe interaction with host (Ramirez-Prado et al, 2018).…”