苹果TIFY家族基因鉴定及其在虫害胁迫下的表达分析

Identification of TIFY Family in Apple and Their Expression Analysis Under Insect Stress

利用生物信息学方法在苹果全基因组中鉴定了TIFY转录因子家族基因,对基因结构、蛋白保守基序和进化关系进行了分析,同时基于新疆野苹果(Malus sieversii)转录组数据分析,明确了苹果TIFY家族基因在虫害胁迫条件下的差异表达情况。共鉴定到了16个苹果TIFY基因,其蛋白质大小介于209~449 aa之间。16个TIFY基因分布于苹果8条染色体中,所有的MdTIFY蛋白都具有保守的TIFY结构域。其中8个苹果MdTIFY与新疆野苹果转录组测序拼接转录本对应,这些基因均含有保守的TIFY功能域,多物种进化分析表明该类蛋白可聚类成7个组。7个TIFY基因的表达量在不同处理间表现出显著差异,虫害侵染后,抗虫株系中MsTIFY10B-a表达量升高34倍,MsTIFY9-c上升5.2倍。同时抗虫株系在自然条件下茉莉酸—异亮氨酸含量显著高于敏感株系。新疆野苹果中重要抗虫响应基因MsTIFY10B-a和MsTIFY9-c位于预测关联网络节点中心位置,使它们在调节植物对生物胁迫的响应中发挥重要作用。

The TIFY transcription factors in the apple were identified using bioinformatics methods.The gene structure,conserved motifs and evolutionary relationship were analyzed.Meanwhile,the differential expression of apple TIFY family member genes under insect Agrilus mari stress conditions was determined based on Malus sieversii transcriptome data analysis.A total of 16 TIFY transcription factors were identified through analysis,which encodes proteins between 209-449 aa.The 16 MdTIFY genes are located on the 8 chromosomes of apples,and all MdTIFY proteins have conserved TIFY domains.Among them,eight MdTIFY correspond to the spliced transcripts of M.sieversii transcriptome sequencing.These genes all contain conserved TIFY functional domains.Multi-species phylogeny analyses showed that these proteins can be clustered into 7 groups.The expression levels of the seven TIFY genes showed significant differences among different treatments.After pest infestation,the expression of MsTIFY10B-a increased by 34-fold in insect-resistant plants,and the expression of MsTIFY9-c increased by 5.2-fold.Meanwhile the contents of jasmonic acid-isoleucine(JA-Ile)in insect-resistant plants were significantly higher than that of sensitive plants.The important insect-resistance response genes,MsTIFY10B-a and MsTIFY9-c,are located in the key nodes of association network in M.sieversii,being as important regulators during the plant responses tobiotic stresses.