论文部分内容阅读
以铁炮百合(Lilium longiflorum)‘白天堂’为试材,采用RACE方法克隆到了1个热激转录因子(Heat shock transcription factor,HSF)A家族全长基因。该基因包含1个编码315个氨基酸的开放阅读框。对推定的氨基酸序列进行聚类分析,与已知的水稻5个HSFA2同源性较高,是1个新的HSFA2编码基因,命名为LlHSFA2b。经过与已报道的番茄、拟南芥、水稻和百合的HSFA2序列比对分析,该基因编码的HSF蛋白具有热激转录因子所具备的典型结构域和调控元件,不同的是,它缺少1个转录激活域和核输出信号。半定量RT-PCR分析表明,该基因特异地受高温和H2O2诱导表达。荧光定量PCR表明:该基因在百合根、鳞茎和叶片中均受热激诱导表达,且表达量无明显差异;37℃热激处理下,与已报道的LlHSFA2a相比,LlHSFA2b表达时间点和表达量的峰值均提前。这些结果说明,本试验中克隆到了1个新的HSFA2编码基因,与LlHSFA2a相比,该基因可能参与了百合早期热信号传导过程。
A full-length heat shock transcription factor (HSF) family A gene was cloned by RACE using ’White Heaven’ from Lilium longiflorum. This gene contains an open reading frame encoding 315 amino acids. Cluster analysis of putative amino acid sequences showed high homology with five known HSFA2s in rice, and was a new HSFA2-encoding gene named LHSSFA2b. Compared with the reported HSFA2 sequence alignment of tomato, Arabidopsis thaliana, rice and lily, the HSF protein encoded by this gene possesses typical domains and regulatory elements of heat shock transcription factor, except that it lacks one Transcriptional activation domains and nuclear export signals. Semi-quantitative RT-PCR analysis showed that the gene was specifically induced by high temperature and H2O2. Fluorescence quantitative PCR showed that the expression of LlHSFA2b in lily root, bulb and leaf was induced by heat shock, and the expression level had no significant difference. Compared with LlHSFA2a reported at 37 ℃, LlHSFA2b expression time point and expression level The peaks are ahead of schedule. These results indicate that a new HSFA2 gene was cloned in this study. Compared with LHSHSFA2a, the gene may be involved in early heat signal transduction.