Next-generation mapping of the salicylic acid signaling hub and transcriptional cascade  

作　　者：Jordan Powers Xing Zhang Andres VReyes Raul Zavaliev Roni Ochakovski Shou-Ling Xu Xinnian Dong 

机构地区：[1]Howard Hughes Medical Institute,Duke University,Durham,NC 27708,USA [2]University Program in Genetics and Genomics,Duke University,Durham,NC 27708,USA [3]Carnegie Institute for Science,Stanford University,Stanford,CA 94305,USA

出　　处：《Molecular Plant》2024年第10期1558-1572,共15页分子植物（英文版）

基　　金：supported by grants from the National Institutes of Health(NIH)1R35GM118036 and the Howard Hughes Medical Institute(to X.D.),NIH 5T32GM007754-40(to J.P.);NIH R01GM135706(to S.-L.X.)and its diversity supplement(to A.V.R.),as well as the Carnegie endowment to the Carnegie mass spectrometry facility.

摘　　要：For over 60 years,salicylic acid(SA)has been known as a plant immune signal required for basal and systemic acquired resistance.SA activates these immune responses by reprogramming∼20%of the transcriptome through NPR1.However,components in the NPR1 signaling hub,which appears as nuclear condensates,and the NPR1 signaling cascade have remained elusive due to difficulties in studying this transcriptional cofactor,whose chromatin association is indirect and likely transient.To overcome this challenge,we applied TurboID to divulge the NPR1 proxiome,which detected almost all known NPR1 interactors as well as new components of transcription-related complexes.Testing of new components showed that chromatin remodeling and histone demethylation contribute to SA-induced resistance.Globally,the NPR1 proxiome has a striking similarity to the proxiome of GBPL3 that is involved in SA synthesis,except for associated transcription factors(TFs),suggesting that common regulatory modules are recruited to reprogram specific transcriptomes by transcriptional cofactors,like NPR1,through binding to unique TFs.Stepwise green fluorescent protein-tagged factor cleavage under target and release using nuclease(greenCUT&RUN)analyses showed that,upon SA induction,NPR1 initiates the transcriptional cascade primarily through association with TGACG-binding TFs to induce expression of secondary TFs,predominantly WRKYs.Further,WRKY54 and WRKY70 were identified to play a major role in inducing immune-output genes without interacting with NPR1 at the chromatin.Moreover,loss of condensate formation function of NPR1 decreases its chromatin association and transcriptional activity,indicating the importance of condensates in organizing the NPR1 signaling hub and initiating the transcriptional cascade.Collectively,this study demonstrates how combinatorial applications of TurboID and stepwise greenCUT&RUN transcend traditional genetic methods to globally map signaling hubs and transcriptional cascades for in-depth explorations.

关 键 词：salicylic acid-induced transcription NPR1 TGA WRKY TFs greenCUT&RUN TurbolD 

分 类 号：Q94[生物学—植物学]