芥菜WOX基因家族的全基因组鉴定与分析

Genome-wide identification and characterization of the WOX gene family in Brassica juncea

摘要:

WUSCHEL相关-同源盒（WUSCHEL related-homeobox，WOX）基因家族是一类植物特有的转录因子基因家族，在植物的生长发育过程中发挥重要作用。本研究利用芥菜（Brassica juncea）基因组数据，通过HUMMER、Smart等软件进行检索筛选，共鉴定出51个WOX基因家族成员。利用Expasy在线软件对这些家族成员的蛋白质分子量、氨基酸序列长度、等电点等进行分析，并利用生物信息学软件对芥菜WOX基因家族进化关系、保守区域、基因结构等进行系统性分析，将芥菜WOX基因家族分为古老支、中间支和WUS支/现代支3个亚家族。结构分析表明，同一亚家族内的WOX转录因子家族成员的保守结构域的种类、组织形式以及基因结构具有高度的一致性，而不同亚家族之间呈现一定的多样性。51个WOX基因不均匀分布于芥菜18条染色体上，这些基因的启动子大多含有响应光、激素和非生物逆境胁迫相关的顺式作用元件。利用转录组数据和实时荧光定量PCR （real-time fluorescence quantitative PCR，qRT-PCR）分析发现，芥菜WOX基因的表达具有时空特异性，其中BjuWOX25、BjuWOX33、BjuWOX49可能在角果的发育中发挥重要作用，BjuWOX10、BjuWOX32和BjuWOX11、BjuWOX23分别在干旱和高温胁迫响应中具有重要功能。上述结果为芥菜WOX基因家族的功能研究奠定了基础。

Abstract:

The WUSCHEL related-homeobox (WOX) family is one of the plant-specific transcription factor families, playing important roles in plant growth and development. In this study, 51 WOX gene family members were identified from the genome data of Brassica juncea by searching and screening with HUMMER, Smart and other software. Their protein molecular weight, amino acids numbers, and isoelectric point were analyzed by using Expasy online software. Furthermore, bioinformatics software was used to systematically analyze the evolutionary relationship, conservative region, and gene structure of the WOX gene family. The mustard WOX gene family was divided into three subfamilies:ancient clade, intermediate clade, and WUS clade/modern clade. Structural analysis showed that the type, organization form and gene structure of the conservative domain of WOX transcription factor family members in the same subfamily were highly consistent, while there was a certain diversity among different subfamilies. 51 WOX genes are distributed unevenly on 18 chromosomes of mustard. Most of the promoters of these genes contain cis acting elements related to light, hormone and abiotic stress. Using transcriptome data and real-time fluorescence quantitative PCR (qRT-PCR) analysis, it was found that the expression of mustard WOX gene was spatio-temporal specific, among which BjuWOX25, BjuWOX33, and BjuWOX49might play an important role in the development of silique, and BjuWOX10, BjuWOX32, and BjuWOX11, BjuWOX23 respectively might play an important role in the response to drought and high temperature stresses. The above results may facilitate the functional study of mustard WOX gene family.