A banana NAC transcription factor (MusaSNAC1) impart drought tolerance by modulating stomatal closure and H2O2 content
MusaSNAC1 function in H2O2 mediated stomatal closure and promote drought tolerance by directly binding to CGT[A/G] motif in regulatory region of multiple stress-related genes.
Drought is a abiotic stress-condition, causing reduced plant growth and diminished crop yield. Guard cells of the stomata control photosynthesis and transpiration by regulating CO2 exchange and water loss, thus affecting growth and crop yield. Roles of NAC (NAM, ATAF1/2 and CUC2) protein in regulation of stress-conditions has been well documented however, their control over stomatal aperture is largely unknown. In this study we report a banana NAC protein, MusaSNAC1 which induced stomatal closure by elevating H2O2 content in guard cells during drought stress. Overexpression of MusaSNAC1 in banana resulted in higher number of stomata closure causing reduced water loss and thus elevated drought-tolerance. During drought, expression of GUS (β-glucuronidase) under P MusaSNAC1 was remarkably elevated in guard cells of stomata which correlated with its function as a transcription factor regulating stomatal aperture closing. MusaSNAC1 is a transcriptional activator belonging to SNAC subgroup and its 5′-upstream region contain multiple Dof1 elements as well as stress-associated cis-elements. Moreover, MusaSNAC1 also regulate multiple stress-related genes by binding to core site of NAC-proteins CGT[A/G] in their 5′-upstream region. Results indicated an interesting mechanism of drought tolerance through stomatal closure by H2O2 generation in guard cells, regulated by a NAC-protein in banana.
KeywordsMusa Banana NAC Drought H2O2 Stomata
Authors thank, Head, Nuclear Agriculture and Biotechnology Division, BARC for support and encouragement. The work was supported from funding of Department of Atomic Energy, Government of India.
SN, HT, and TG conceived and designed research. SN, and HT conducted the experiments and analyzed data. SN, HT, and TG wrote the manuscript. All authors read and approved the manuscript.
Compliance with ethical standards
Conflict of interest
The authors declares that they have no conflict of interest.
- Buchanan-Wollaston V, Page T, Harrison E, Breeze E, Lim PO, Nam HG, Lin JF, Wu SH, Swidzinski J, Ishizaki K, Leaver CJ (2005) Comparative transcriptome analysis reveals significant differences in gene expression and signalling pathways between developmental and dark/starvation induced senescence in Arabidopsis. Plant J 42:567–585CrossRefPubMedGoogle Scholar
- FAOSTAT (2013–2014). http://fao.org
- Surendar KK, Devi DD, Ravi I, Krishnakumar S, Kumar SR, Velayudham K (2013) Water stress in banana—a review. Bull Environ Pharmacol Life Sci 2:01–18Google Scholar
- Tran LS, Nakashima K, Sakuma Y, Simpson SD, Fujita Y, Maruyama K, Fujita M, Seki M, Shinozaki K, Yamaguchi-Shinozaki K (2004) Isolation and functional analysis of Arabidopsis stress-inducible NAC transcription factors that bind to a drought-responsive cis-element in the early responsive to dehydration stress 1 promoter. Plant Cell 16:2481–2498CrossRefPubMedPubMedCentralGoogle Scholar
- Vanhove AC, Vermaelen W, Panis B, Swennen R, Carpentier SC (2012) Screening the banana biodiversity for drought tolerance: can an in vitro growth model and proteomics be used as a tool to discover tolerant varieties and understand homeostasis. Front Plant Sci 3:176CrossRefPubMedPubMedCentralGoogle Scholar
- Wu A, Allu AD, Garapati P, Siddiqui H, Dortay H, Zanor MI, Asensi-Fabado MA, Munné Bosch S, Antonio C, Tohge T, Fernie AR, Kaufmann K, Xue GP, Mueller-Roeber B, Balazadeh S (2012) JUNGBRUNNEN1, a reactive oxygen species-responsive NAC transcription factor, regulates longevity in Arabidopsis. Plant Cell 24:482–506CrossRefPubMedPubMedCentralGoogle Scholar