AUTHOR=Li Nan-Yang , Zhou Lei , Zhang Dan-Dan , Klosterman Steven J. , Li Ting-Gang , Gui Yue-Jing , Kong Zhi-Qiang , Ma Xue-Feng , Short Dylan P. G. , Zhang Wen-Qi , Li Jun-Jiao , Subbarao Krishna V. , Chen Jie-Yin , Dai Xiao-Feng 

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

JOURNAL=Frontiers in Plant Science

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2018.00119

DOI=10.3389/fpls.2018.00119

ISSN=1664-462X

ABSTRACT=<p>Verticillium wilt caused by <italic>Verticillium dahliae</italic> 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 <italic>GbaNA1</italic> that confers resistance to the highly virulent <italic>V. dahliae</italic> isolate Vd991. In this study, we expressed cotton <italic>GbaNA1</italic> in the heterologous system of <italic>Arabidopsis thaliana</italic> and investigated the defense response mediated by GbaNA1 following inoculations with <italic>V. dahliae</italic>. Heterologous expression of <italic>GbaNA1</italic> conferred Verticillium wilt resistance in <italic>A. thaliana</italic>. Moreover, overexpression of <italic>GbaNA1</italic> enabled recovery of the resistance phenotype of <italic>A. thaliana</italic> mutants that had lost the function of <italic>GbaNA1</italic> ortholog gene. Investigations of the defense response in <italic>A. thaliana</italic> 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 <italic>GbaNA1</italic>. Intriguingly, overexpression of the <italic>GbaNA1</italic> ortholog from <italic>Gossypium hirsutum</italic> (<italic>GhNA1</italic>) in <italic>A. thaliana</italic> did not induce the defense response of ROS production due to the premature termination of <italic>GhNA1</italic>, which lacks the encoded NB-ARC and LRR motifs. <italic>GbaNA1</italic> therefore confers Verticillium wilt resistance in <italic>A. thaliana</italic> by the activation of ROS production and ethylene signaling. These results demonstrate the functional conservation of the NBS-LRR-encoding <italic>GbaNA1</italic> in a heterologous system, and the mechanism of this resistance, both of which may prove valuable in incorporating <italic>GbaNA1</italic>-mediated resistance into other plant species.</p>