Identification and functional characterization of a rice NAC gene involved in the regulation of leaf senescence

BMC Plant Biology

Research Article

Yong Zhou¹  Fei Zhou¹  Weifeng Huang¹  Taiyu Chen¹  Yongjun Lin¹  Li Liu² 

[1] National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, 430070, Wuhan, China;Plant Reproductive Biology, Mail Stop 5, University of California, 1 Shields Avenue, 95616-8780, Davis, CA, USA;

关键词: Chlorophyll;    Leaf senescence;    NAC;    JA;    Oryza sativa;   

DOI  :  10.1186/1471-2229-13-132

 received in 2013-04-29, accepted in 2013-08-13,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundAs the final stage of leaf development, leaf senescence may cause the decline of photosynthesis and gradual reduction of carbon assimilation, which makes it a possible limiting factor for crop yield. NACs are plant-specific transcription factors and some NACs have been confirmed to play important roles in regulating leaf senescence.ResultsIn this study, we reported a member of the NAC transcription factor family named OsNAP whose expression is associated with leaf senescence, and investigated its preliminary function during the process of leaf senescence. The results of qRT-PCR showed that the OsNAP transcripts were accumulated gradually in response to leaf senescence and treatment with methyl jasmonic acid (MeJA). A subcellular localization assay indicated that OsNAP is a nuclear-localized protein. Yeast one-hybrid experiments indicated that OsNAP can bind the NAC recognition site (NACRS)-like sequence. OsNAP-overexpressing transgenic plants displayed an accelerated leaf senescence phenotype at the grain-filling stage, which might be caused by the elevated JA levels and the increased expression of the JA biosynthesis-related genes LOX2 and AOC1, and showed enhanced tolerance ability to MeJA treatment at the seedling stage. Nevertheless, the leaf senescence process was delayed in OsNAP RNAi transgenic plants with a dramatic drop in JA levels and with decreased expression levels of the JA biosynthesis-related genes AOS2, AOC1 and OPR7.ConclusionsThese results suggest that OsNAP acts as a positive regulator of leaf senescence and this regulation may occur via the JA pathway.

【 授权许可】

Unknown   
© Zhou et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.