Lin Qiong, Jiang Qing, Lin Juanying, Wang Dengliang, Li Shaojia, Liu Chunrong, Sun Chongde, Chen Kunsong
Laboratory of Fruit Quality Biology/The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, PR China.
Quzhou Academy of Agricultural Science, Quzhou 324000, Zhejiang Province, PR China.
Gene. 2015 Apr 1;559(2):129-36. doi: 10.1016/j.gene.2015.01.024. Epub 2015 Jan 14.
Heat shock transcription factors (Hsfs) play a role in plant responses to stress. Citrus is an economically important fruit whose genome has been fully sequenced. So far, no detailed characterization of the Hsf gene family is available for citrus. A genome-wide analysis was carried out in Citrus clementina to identify Hsf genes, named CcHsfs. Eighteen CcHsfs were identified and classified into three main clades (clades A, B and C) according to the structural characteristics and the phylogenetic comparison with Arabidopsis and tomato. MEME motif analysis highlighted the conserved DBD and HR-A/B domains, which were similar to Hsf protein structures in other species. Gene expression analysis in Ponkan (Citrus reticulata Blanco cv. Ponkan) fruit identified 14 Hsf genes, named CrHsf, as important candidates for a role in fruit development and ripening, and showed seven genes to be expressed in response to hot air stress. CrHsfB2a and CrHsfB5 were considered to be important regulators of citrate content and showed variation in both developmentally-related and hot air-triggered citrate degradation processes. In summary, the data obtained from this investigation provides the basis for further study to dissect Hsf function during fruit development as well as in response to heat stress and also emphasizes the potential importance of CrHsfs in regulation of citrate metabolism in citrus fruit.
热激转录因子（Hsfs）在植物应对胁迫过程中发挥作用。柑橘是一种具有重要经济价值的水果，其基因组已被完全测序。到目前为止，尚未有关于柑橘热激转录因子基因家族的详细特征描述。对克莱门氏柑橘进行了全基因组分析，以鉴定热激转录因子基因，命名为CcHsfs。共鉴定出18个CcHsfs，并根据其结构特征以及与拟南芥和番茄的系统发育比较，将它们分为三个主要分支（A、B和C分支）。MEME基序分析突出了保守的DNA结合结构域（DBD）和HR-A/B结构域，这些结构域与其他物种的热激转录因子蛋白结构相似。对椪柑（Citrus reticulata Blanco cv. Ponkan）果实进行的基因表达分析鉴定出14个热激转录因子基因，命名为CrHsf，它们是果实发育和成熟过程中发挥作用的重要候选基因，并显示有7个基因在热空气胁迫下表达。CrHsfB2a和CrHsfB5被认为是柠檬酸含量的重要调节因子，并且在与发育相关的和热空气触发的柠檬酸降解过程中均表现出差异。总之，本研究获得的数据为进一步研究热激转录因子在果实发育过程中以及对热胁迫响应中的功能奠定了基础，同时也强调了CrHsfs在柑橘果实柠檬酸代谢调控中的潜在重要性。
