木薯JAZ基因的鉴定和对不同胁迫的响应模式

Identification of Manihot esculenta JAZ Genes and Their Response Pattern to Different Stresses

摘要:

JAZ (jasmonate ZIM-domain)蛋白在植物响应生物与非生物胁迫方面具有重要作用。该研究利用生物信息学在木薯(Manihot esculenta)中鉴定到16个JAZ基因，不均匀分布在11条染色体上。16个JAZ基因中有7对呈共线性关系，全为片段重复基因，其中4对相似度高的共线性基因的Ka/Ks小于1，表明木薯JAZ家族基因在进化中受到纯化选择。13个JAZ蛋白包含ZIM、Jas和NT结构域，3个蛋白NT结构域缺失。13个JAZ基因包含完整的UTR、内含子和外显子序列，其余缺失UTR区或者内含子。JAZ家族基因启动子区存在多个响应胁迫、脱落酸和水杨酸的顺式作用元件。组织特异性表达分析结果表明花和块根中有较多高表达JAZ基因(如MeJAZ2/MeJAZ4/MeJAZ6/MeJAZ9/MeJAZ13)，其次为茎杆。同时大多数MeJAZ基因响应多种非生物胁迫，如干旱诱导较多MeJAZ基因的表达，MeJAZ16基因被水杨酸显著诱导, 这为木薯遗传改良筛选优质基因提供参考。

关键词:木薯;JAZ家族基因;组织特异性表达;非生物胁迫

Abstract:

Jasmonate ZIM-domain (JAZ) proteins play an important role in plant response to biological and abiotic stresses. There were 16 MeJAZ genes identified in Manihot esculenta by bioinformatics, which were unevenly distributed on 11 chromosomes. Among the 16 MeJAZ genes, 7 pairs of gene showed collinear relationship, all of which were fragment repeat genes, and the Ka/Ks of the 4 collinear genes with high similarity were less than 1, indicating that the JAZ family genes were selected for purification in evolution. Thirteen MeJAZ proteins contained ZIM, Jas and NT domains, and the other 3 MeJAZ proteins were missing NT domains. Thirteen MeJAZ genes contained complete UTR, intron and exon sequences, the other genes lacked the UTR region or intron sequences. The promoter region of MeJAZs contained multiple cis-acting elements responsing to abiotic stresses, ABA and SA. There were more MeJAZs with high expression in root tuber and flower, such as MeJAZ2/MeJAZ4/MeJAZ6/MeJAZ9/MeJAZ13, followed by stems. At the same time, most of MeJAZ genes responded to multiple abiotic stresses, drought induced the expression of more MeJAZ genes, and the MeJAZ16 gene was significantly induced by SA. Therefore, these would provide a reference for genetic improvement and selection of high-quality genes in Manihot esculenta.

Key words:Manihot esculenta;JAZ family gene;Tissue specific expression;Abiotic stress