Premium
The R2R3‐MYB transcription factor AtMYB49 modulates salt tolerance in Arabidopsis by modulating the cuticle formation and antioxidant defence
Author(s) -
Zhang Ping,
Wang Ruling,
Yang Xianpeng,
Ju Qiong,
Li Weiqiang,
Lü Shiyou,
Tran LamSon Phan,
Xu Jin
Publication year - 2020
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/pce.13784
Subject(s) - cutin , arabidopsis , transcription factor , myb , microbiology and biotechnology , cuticle (hair) , biology , arabidopsis thaliana , mutant , biochemistry , abscisic acid , botany , chemistry , gene , genetics
Salt stress activates defence responses in plants, including changes in leaf surface structure. Here, we showed that the transcriptional activation of cutin deposition and antioxidant defence by the R2R3‐type MYB transcription factor AtMYB49 contributed to salt tolerance in Arabidopsis thaliana . Characterization of loss‐of‐function myb49 mutants, and chimeric AtMYB49‐SRDX‐ overexpressing SRDX49 transcriptional repressor and AtMYB49 ‐overexpressing ( OX49 ) overexpressor plants demonstrated a positive role of AtMYB49 in salt tolerance. Transcriptome analysis revealed that many genes belonging to the category “cutin, suberin and wax biosyntheses” were markedly up‐regulated and down‐regulated in OX49 and SRDX49 plants, respectively, under normal and/or salt stress conditions. Some of these differentially expressed genes, including MYB41 , ASFT , FACT and CYP86B1 , were also shown to be the direct targets of AtMYB49 and activated by AtMYB49. Biochemical analysis indicated that AtMYB49 modulated cutin deposition in the leaves. Importantly, cuticular transpiration, chlorophyll leaching and toluidine blue‐staining assays revealed a link between increased AtMYB49‐mediated cutin deposition in leaves and enhanced salt tolerance. Additionally, increased AtMYB49 expression elevated Ca 2+ level in leaves and improved antioxidant capacity by up‐regulating genes encoding peroxidases and late embryogenesis abundant proteins. These results suggest that genetic manipulation of AtMYB49 may provide a novel way to improve salt tolerance in plants.