Potassium transporter OsHAK9 regulates seed germination under salt stress by preventing gibberellin degradation through mediating OsGA2ox7 in rice  

作　　者：Peng Zeng Ting Xie Jiaxin Shen Taokai Liang Lu Yin Kexin Liu Ying He Mingming Chen Haijuan Tang Sunlu Chen Sergey Shabala Hongsheng Zhang Jinping Cheng 

机构地区：[1]National Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization,Jiangsu Collaborative Innovation Center for Modern Crop Production,Hainan Yazhou Bay Seed Lab,Jiangsu Province Engineering Research Center of Seed Industry Science and Technology,Nanjing Agricultural University,Nanjing 210095,China [2]International Research Center for Environmental Membrane Biology,Foshan University,Foshan 528000,China [3]School of Biological Sciences,University of Western Australia,Crawley WA 6009,Australia

出　　处：《Journal of Integrative Plant Biology》2024年第4期731-748,共18页植物学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.32272169,32000377,32172037,and 31601387);the Natural Science Foundation of Guangdong Province(Grant No.2022A1515110449);the Hainan Yazhou Bay Seed Laboratory(project of B21HJ1002)。

摘　　要：Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.

关 键 词：GDSS GIBBERELLINS potassium transporter RICE salt tolerance seed germination 

分 类 号：S511[农业科学—作物学]