Cu/Zn superoxide dismutase (VdSOD1) mediates reactive oxygen species detoxification and modulates virulence in Verticillium dahliae.
Li TianJunjiao LiCaimin HuangDandan ZhangYan XuXingyong YangJian SongDan WangNianwei QiuDylan P G ShortPatrik InderbitzinKrishna V SubbaraoJie-Yin ChenXiao-Feng DaiPublished in: Molecular plant pathology (2021)
The accumulation of reactive oxygen species (ROS) is a widespread defence mechanism in higher plants against pathogen attack and sometimes is the cause of cell death that facilitates attack by necrotrophic pathogens. Plant pathogens use superoxide dismutase (SOD) to scavenge ROS derived from their own metabolism or generated from host defence. The significance and roles of SODs in the vascular plant pathogen Verticillium dahliae are unclear. Our previous study showed a significant upregulation of Cu/Zn-SOD1 (VdSOD1) in cotton tissues following V. dahliae infection, suggesting that it may play a role in pathogen virulence. Here, we constructed VdSOD1 deletion mutants (ΔSOD1) and investigated its function in scavenging ROS and promoting pathogen virulence. ΔSOD1 had normal growth and conidiation but exhibited significantly higher sensitivity to the intracellular ROS generator menadione. Despite lacking a signal peptide, assays in vitro by western blot and in vivo by confocal microscopy revealed that secretion of VdSOD1 is dependent on the Golgi reassembly stacking protein (VdGRASP). Both menadione-treated ΔSOD1 and cotton roots infected with ΔSOD1 accumulated more O 2 - and less H2 O2 than with the wildtype strain. The absence of a functioning VdSOD1 significantly reduced symptom severity and pathogen colonization in both cotton and Nicotiana benthamiana. VdSOD1 is nonessential for growth or viability of V. dahliae, but is involved in the detoxification of both intracellular ROS and host-generated extracellular ROS, and contributes significantly to virulence in V. dahliae.
Keyphrases
- reactive oxygen species
- cell death
- amyotrophic lateral sclerosis
- antimicrobial resistance
- escherichia coli
- pseudomonas aeruginosa
- candida albicans
- biofilm formation
- staphylococcus aureus
- dna damage
- gram negative
- hydrogen peroxide
- nitric oxide
- high resolution
- wastewater treatment
- south africa
- cystic fibrosis
- patient reported
- binding protein
- long non coding rna