OsNAC120 balances plant growth and drought tolerance by integrating GA and ABA signaling in rice  

作　　者：Zizhao Xie Liang Jin Ying Sun Chenghang Zhan Siqi Tang Tian Qin Nian Liu Junli Huang 

机构地区：[1]Key Laboratory of Biorheological Science and Technology of Ministry of Education,Bioengineering College of Chongqing University,Chongqing,China

出　　处：《Plant Communications》2024年第3期197-215,共19页植物通讯（英文）

基　　金：supported by the National Natural Science Foundation of China (32071985);the Chongqing Special Key Project for Technological Innovation and Application Development (CSTB2022TIAD-KPX0018,CSTB2022TIAD-KPX0016,CSTB2022TIAD-KPX0015).

摘　　要：The crosstalk between gibberellin(GA)and abscisic acid(ABA)signaling is crucial for balancing plant growth and adaption to environmental stress.Nevertheless,the molecular mechanism of their mutual antagonism still remains to be fully claried.In this study,we found that knockout of the rice NAC(NAM,ATAF1/2,CUC2)tran-scription factor gene OsNAC120 inhibits plant growth but enhances drought tolerance,whereas OsNAC120 overexpression produces the opposite results.Exogenous GA can rescue the semi-dwarf phenotype of osnac120 mutants,and further study showed that OsNAC120 promotes GA biosynthesis by transcriptionally activating the GA biosynthetic genes OsGA20ox1 and OsGA20ox3.The DELLA protein SLENDER RICE1(SLR1)interacts with OsNAC120 and impedes its transactivation ability,and GA treatment can remove the inhi-bition of transactivation activity caused by SLR1.On the other hand,OsNAC120 negatively regulates rice drought tolerance by repressing ABA-induced stomatal closure.Mechanistic investigation revealed that OsNAC120 inhibits ABA biosynthesis via transcriptional repression of the ABA biosynthetic genes OsNCED3 and OsNCED4.Rice OSMOTIC STRESS/ABA-ACTIVATED PROTEIN KINASE 9(OsSAPK9)physically interacts with OsNAC120 and mediates its phosphorylation,which results in OsNAC120 degradation.ABA treatment ac-celerates OsNAC120 degradation and reduces its transactivation activity.Together,our findings provide evidence that OsNAC120 plays critical roles in balancing GA-mediated growth and ABA-induced drought tolerance in rice.This research will help us to understand the mechanisms underlying the trade-off between plant growth and stress tolerance and to engineer stress-resistant,high-yielding crops.

关 键 词：abscisic acid ABA drought stress GIBBERELLIN GA OsNAC120 OsSAPK9 RICE Oryza sativa L. SLR1 

分 类 号：S511[农业科学—作物学]