EuPOD基因克隆与焦枯病菌胁迫表达分析

植物过氧化物酶是植物体内活性氧清除过程中的关键酶之一,在植物的抗逆性中发挥着重要作用。以对焦枯病菌高抗品系尾细桉为材料,克隆得到一个 POD 基因序列,并命名为 EuPOD,通过实时荧光定量聚合酶链式反应( qRT￣PCR)检验该基因在尾细桉叶片中的表达。结果表明该基因cDNA长999 bp,其编码蛋白由332个氨基酸组成；基于氨基酸序列的系统进化树分析表明, EuPOD在进化上与蓖麻、可可、苹果的同源基因亲缘关系较近,相似性达到了75％,与拟南芥的相似性达到65％,与水稻的相似性较低,只有48％。 EuPOD在桉树焦枯病菌侵染后不同时间所受诱导表达量不同,在12 h的表达量达到高峰。

Cloning of EuPOD gene from Eucalyptus grandis×E. tereticornis and its expression analysis infected by Calonectria pseudoreteaudii

Peroxidase( POD) is one of the key enzymes responsible for removal of reactive oxygen in plant, and plays a crucial role in stress response. In this study, a POD gene was cloned from the Calonectria resistant clone Eucalyptus grandis×E. tereticornis, and named as EuPOD. The expression of EuPOD gene in the leave was tested by qRT￣PCR. The cDNA sequence of EuPOD were 999 bp, and encoded a protein consisting of 332 amino acids. A phylogenic tree was constructed based on the protein sequence. It showed that EuPOD was relatively close to homologous gene from Ricinus communis L., Theobroma cacao L., Malus domestica Borkh. Their sequence similarity were over 75%. EuPOD had more than 65% sequence similarity with Arabidopsis thaliana, and 48% to Oryza sativa Japonica Group. QRT￣PCR analysis showed that the expression level of EuPOD increased after infection by C. pseudoreteaudii, and up to a peak after 12 h.