Abstract
Drought stress is a crucial environmental factor that limits plant growth,development,and productivity.Autophagy of misfolded proteins can help alleviate the damage caused in plants experiencing drought.However,the mechanism of autophagy-mediated drought tolerance in plants remains largely unknown.Here,we cloned the gene for a maize(Zea mays)selective autophagy receptor,NEXT TO BRCA1 GENE 1(ZmNBR1),and identified its role in the re-sponse to drought stress.We observed that drought stress increased the accumulation of autophago-somes.RNA sequencing and reverse transcription-quantitative polymerase chain reaction showed that ZmNBR1 is markedly induced by drought stress.ZmNBR1 overexpression enhanced drought tolerance,while its knockdown reduced drought tol-erance in maize.Our results established that ZmNBR1 mediates the increase in autophagosomes and autophagic activity under drought stress.ZmNBR1 also affects the expression of genes related to autophagy under drought stress.Moreover,we determined that BRASSINOSTEROID INSENSITIVE 1A(ZmBRI1a),a brassinosteroid receptor of the BRI1-like family,interacts with ZmNBR1.Phenotype analysis showed that ZmBRI1a negatively regulates drought tolerance in maize,and genetic analysis in-dicated that ZmNBR1 acts upstream of ZmBRI1a in regulating drought tolerance.Furthermore,ZmNBR1 facilitates the autophagic degradation of ZmBRI1a under drought stress.Taken together,our results reveal that ZmNBR1 regulates the expression of autophagy-related genes,thereby increasing auto-phagic activity and promoting the autophagic deg-radation of ZmBRI1a under drought stress,thus en-hancing drought tolerance in maize.These findings provide new insights into the autophagy degradation of brassinosteroid signaling components by the au-tophagy receptor NBR1 under drought stress.
基金项目
National Natural Science Foundation of China(32201707)
Natural Science Foundation of Jiangsu Province(BK20220999)
Fundamental Research Funds for the Central Universities(KYQN2023025)
China Postdoctoral Science Foundation(2021M701739)
China Postdoctoral Science Foundation(2023T160323)
Jiangsu Funding Program for Excellent Postdoctoral Talent(2022ZB330)
Open Competition Mechanism to Select the Best Candidates Fund of Jiangsu Province(JBGS[2021]012)
Key Research and Development Program of Ningxia Hui Autonomous Region(2023BCF01009)
Achievement Transformation Fund Project of Hainan Research Institute of Nanjing Agricultural University(NAUSY-CG-YB07)
NETL
NSTL
万方数据