RhNAC3, a stress‐associated NAC transcription factor, has a role in dehydration tolerance through regulating osmotic stress‐related genes in rose petals. Issue 1 (7th September 2013)

• Record Type: Journal Article
• Authors: Jiang, Xinqiang; Zhang, Changqing; Lü, Peitao; Jiang, Guimei; Liu, Xiaowei; Dai, Fanwei; Gao, Junping
• Is Part Of: Plant biotechnology journal. Volume 12:Issue 1(2014:Jan.)
• Page Start: 38
• Page End: 48
• Publication Date: 2013-09-07
• Subjects: Plant biotechnology -- Periodicals; Plant genetic engineering -- Periodicals; 630.272
• DOI: 10.1111/pbi.12114
• Languages: English
• ISSNs: 1467-7644

Abstract

<abstract abstract-type="main" id="pbi12114-abs-0001"> <title>Summary</title> <p>Petal cell expansion depends on cell wall metabolism, changes in cell turgor pressure and restructuring of the cytoskeleton, and recovery ability of petal cell expansion is defined as an indicator of dehydration tolerance in flowers. We previously reported that RhNAC2, a development‐related NAC domain transcription factor, confers dehydration tolerance through regulating cell wall‐related genes in rose petals. Here, we identify <italic>RhNAC3</italic>, a novel rose <italic>SNAC</italic> gene, and its expression in petals induced by dehydration, wounding, exogenous ethylene and abscisic acid (ABA). Expression studies in Arabidopsis protoplasts and yeast show that RhNAC3 has transactivation activity along its full length and in the carboxyl‐terminal domain. Silencing <italic>RhNAC3</italic> in rose petals by virus‐induced gene silencing (VIGS) significantly decreased the cell expansion of rose petals under rehydration conditions. In total, 24 of 27 osmotic stress‐related genes were down‐regulated in <italic>RhNAC3</italic>‐silenced rose petals, while only 4 of 22 cell expansion‐related genes were down‐regulated. Overexpression of <italic>RhNAC3</italic> in Arabidopsis gave improved drought tolerance, with lower water loss of leaves in transgenic plants. Arabidopsis ATH1 microarray analysis showed that <italic>RhNAC3</italic> regulated the expression of stress‐responsive genes in overexpressing lines, and further analysis revealed that most of the <italic>RhNAC3‐</italic>up‐regulated genes were involved in the response to osmotic stress. Comparative analysis revealed that different transcription regulation existed between RhNAC3 and RhNAC2. Taken together, these data indicate that <italic>RhNAC3, </italic> as a positive regulator, confers dehydration tolerance of rose petals mainly through regulating osmotic adjustment‐associated genes.</p> </abstract>