Heterologous Expression of the Cotton NBS-LRR Gene GbaNA1 Enhances Verticillium Wilt Resistance in Arabidopsis

Abstract

Verticillium wilt caused by Verticillium dahliae results in severe losses in cotton, and is economically the most destructive disease of this crop. Improving genetic resistance is the cleanest and least expensive option to manage Verticillium wilt. Previously, we identified the island cotton NBS-LRR-encoding gene GbaNA1 that confers resistance to the highly virulent V. dahliae isolate Vd991. In this study, we expressed cotton GbaNA1 in the heterologous system of Arabidopsis thaliana and investigated the defense response mediated by GbaNA1 following inoculations with V. dahliae. Heterologous expression of GbaNA1 conferred Verticillium wilt resistance in A. thaliana. Moreover, overexpression of GbaNA1 enabled recovery of the resistance phenotype of A. thaliana mutants that had lost the function of GbaNA1 ortholog gene. Investigations of the defense response in A. thaliana showed that the reactive oxygen species (ROS) production and the expression of genes associated with the ethylene signaling pathway were enhanced significantly following overexpression of GbaNA1. Intriguingly, overexpression of the GbaNA1 ortholog from Gossypium hirsutum (GhNA1) in A. thaliana did not induce the defense response of ROS production due to the premature termination of GhNA1, which lacks the encoded NB-ARC and LRR motifs. GbaNA1 therefore confers Verticillium wilt resistance in A. thaliana by the activation of ROS production and ethylene signaling. These results demonstrate the functional conservation of the NBS-LRR-encoding GbaNA1 in a heterologous system, and the mechanism of this resistance, both of which may prove valuable in incorporating GbaNA1-mediated resistance into other plant species.

Identifying Verticillium dahliae Resistance in Strawberry Through Disease Screening of Multiple Populations and Image Based Phenotyping

“…Seven TIR-NBS-LRR resistance genes were observed to be up-regulated in Arabidopsis thaliana 24 h after Verticillium co-culturing (Scholz et al, 2018) again indicating NBS-LRRs may play a role in Verticillium resistance. The NBS resistance gene GbaNA1 was found to control disease resistance to Verticillium in cotton and also confer resistance when transformed into A. thaliana (Li et al, 2018a, b). A positive correlation between the number of Verticillium and Fusarium wilt resistance QTL and NBS genes was observed on subgenome A of Cotton (Zhang et al, 2015).…”

The Gossypium hirsutum TIR‐NBS‐LRR gene GhDSC1 mediates resistance against Verticillium wilt

“…ROS accumulation as a Verticillium wilt resistance response also has been reported in association with several other candidate genes, including GbaNA1 (Li et al ., ), Gh‐LYK1 and Gh‐LYK2 (Gu et al ., ) and GbRVd (Yang et al ., ), suggesting that ROS accumulation plays a critical role in cotton resistance to V. dahliae . Furthermore, hormone‐mediated signalling is one of the most important aspects of this defence mechanism, (Fujita et al ., ), and SA, JA and ETH are three main hormones contributing to defence against V. dahliae (Duan et al ., ; Gao et al ., ; Guo et al ., ; He et al ., ; Li et al ., , ; Mo et al ., ; Parkhi et al ., ; Sun et al ., ; Wang et al ., ; Xu et al ., ; Yang et al ., ; Zhang et al ., ; Zuo et al ., ). Several functional studies have explored the roles of novel genes implicated in cotton defence, and some of these modulate JA signalling, such as GbSBT1 (Duan et al ., ), GbSSN (Sun et al ., ), GhNINJA (Wang et al ., ), GhJAZ2 and GhbHLH171 (He et al ., ) and GbSSI1 (Gao et al ., ).…”

The NBS-LRR Gene Class is a Small Family in <em>Cucurbita pepo</em>

“…The blastx against the nr protein database provided significant blast hit (97-100% query cover and 94-100% identity) with C. pepo proteins similar to At4g27220, At5g66900 and At4g33300 genes. The NBS-LRR gene At4g27220 is the orthologue of the cotton gene GbaNA1 that confers resistance to Verticillium wilt caused by Verticillium dahliae [38].…”