Knockdown of Quinolinate Phosphoribosyltransferase Results in Decreased Salicylic Acid-Mediated Pathogen Resistance in Arabidopsis thaliana.
Shengchun LiHaiyan DingYi DengJiang ZhangPublished in: International journal of molecular sciences (2021)
Nicotinamide adenine dinucleotide (NAD) is a pivotal coenzyme that has emerged as a central hub linking redox equilibrium and signal transduction in living cells. The homeostasis of NAD is required for plant growth, development, and adaption to environmental stresses. Quinolinate phosphoribosyltransferase (QPRT) is a key enzyme in NAD de novo synthesis pathway. T-DNA-based disruption of QPRT gene is embryo lethal in Arabidopsis thaliana. Therefore, to investigate the function of QPRT in Arabidopsis, we generated transgenic plants with decreased QPRT using the RNA interference approach. While interference of QPRT gene led to an impairment of NAD biosynthesis, the QPRT RNAi plants did not display distinguishable phenotypes under the optimal condition in comparison with wild-type plants. Intriguingly, they exhibited enhanced sensitivity to an avirulent strain of Pseudomonas syringae pv. tomato (Pst-avrRpt2), which was accompanied by a reduction in salicylic acid (SA) accumulation and down-regulation of pathogenesis-related genes expression as compared with the wild type. Moreover, oxidative stress marker genes including GSTU24, OXI1, AOX1 and FER1 were markedly repressed in the QPRT RNAi plants. Taken together, these data emphasized the importance of QPRT in NAD biosynthesis and immunity defense, suggesting that decreased antibacterial immunity through the alteration of NAD status could be attributed to SA- and reactive oxygen species-dependent pathways.
Keyphrases
- arabidopsis thaliana
- wild type
- living cells
- plant growth
- oxidative stress
- genome wide
- reactive oxygen species
- single molecule
- fluorescent probe
- genome wide identification
- transcription factor
- poor prognosis
- molecular dynamics
- cell wall
- dna methylation
- dna damage
- electronic health record
- climate change
- pregnant women
- genome wide analysis
- signaling pathway
- data analysis
- artificial intelligence
- silver nanoparticles
- heat shock protein