蜻蜓凤梨 AfERF113基因的克隆与表达特性
Cloning and Expression Analysis of AfERF113 in Aechemia fasciata

观赏凤梨是一类重要的热带花卉，但有关其生长发育调控分子机理的研究相对匮乏，这在一定程度上限制了新品种的开发和利用。以热带观赏花卉蜻蜓凤梨（Aechemia fasciata）为材料，在分析蜻蜓凤梨转录组数据的基础上，结合cDNA末端快速扩增（rapid amplification of cDNA ends，RACE）技术克隆了APETALA2/Ethylene Response Element Binding Protein（AP2/EREBP）家族的1个转录因子编码序列，并将其命名为 AfERF113。生物信息学分析表明， AfERF113 cDNA全长1 093 bp，有1个864 bp的开放阅读框（open reading frame，ORF），编码287个氨基酸。蛋白质理化性质分析表明，该蛋白分子质量为29.768 5 ku，理论等电点为6.06，为一类不稳定的酸性亲水蛋白。亚细胞定位软件预测表明该蛋白定位于细胞核。结构域分析表明，该蛋白有1个保守的AP2结构域，分属ERF亚族的B-4类，与拟南芥中所有ERF蛋白的ERF113亲源关系最近。实时荧光定量PCR（quantitative real time PCR，qRT-PCR）结果表明， AfERF113转录本在成熟株的根中表达量最高，且外源乙烯诱导后， AfERF113的表达量论是在幼株还是在成株的各组织中均显著上调。研究结果证实， AfERF113响应了外源乙烯调控，为进一步研究 AfERF113基因的功能及通过基因工程手段调控凤梨科植物生长发育提供了理论依据。
Cultivated bromeliads are important tropical ornamental flowering plants. However, it is little known about its molecular mechanism of growth and development regulation, and which in turn becomes a bottleneck for breeding and exploiting of new varieties. With the ornamental bromeliads Aechemia fasciata as material, based on its transcriptome data, a member of APETALA2/Ethylene Response Element Binding Protein (AP2/EREBP) was isolated by using rapid amplification of cDNA ends (RACE) technology and was named as AfERF113. The length of AfERF113 cDNA was 1 093 bp, with an 864 bp open reading frame (ORF), which encodes a 287-amino acids deduced protein. The protein is acidic hydrophilic and with 29.768 5 ku molecular mass, 6.06 theoretical pI. It is a putative nuclear-localized protein with a conserved AP2 domain. Phylogenetic analysis indicated the domain belong to B-4 group of ERF subfamily and the protein is most close in genetic relationship with Arabidopsis ERF113. Quantitative real-time PCR (qRT-PCR) results showed that the accumulation of AfERF113 transcripts was highest in roots of adult plants compared with other tested tissues of juvenile. Whereas, after treatment with exogenous ethylene for 1 h, the expression level of AfERF113 transcripts showed significant increase in all tested tissues either of juvenile or adult plants, indicating its rapid response to ethylene. These results provided a theoretical basis of further research of AfERF113 features and manipulating the growth and development of bromeliads using genetic approach in the near future.