工业大麻WOX基因家族的全基因组鉴定及表达分析

Genome-wide identification and expression analysis of WOX gene family in industrial hemp

关键词:  工业大麻, WOX基因家族, 全基因组鉴定, 生物信息学分析, 分子育种

Key words:  industrial hemp(Cannabis sativa), WOX gene family, genome-wide identification, bioinformatics analysis, molecular breeding

摘要:

工业大麻是重要的纤维作物,其纤维具有多种独特优势和广泛应用前景,WOX基因家族在调控工业大麻纤维发育与植株生长抗逆过程中具有潜在作用。目前,工业大麻中CsWOX基因家族的功能及其在稳产、增产等关键生物学过程中的作用尚未明晰。因此,该研究利用生物信息学技术手段对工业大麻CsWOX基因开展其理化性质、保守结构域以及表达模式分析,结果表明:(1)从工业大麻中鉴定出11个CsWOX基因家族成员,编码氨基酸数目为223～435 aa; 相对分子量为25 398.30～48 429.45 Da,该基因家族蛋白多数呈酸性且多数定位于细胞核。(2)CsWOX蛋白成员可分为3个分支(古代支、中间支、现代支),现代支含有6个亚支,中间支含有2个亚支,古代支仅1个亚支,同一亚支的WOX转录因子保守基序种类及组织形式存在一定保守性,每个家族成员均含有1个螺旋-环-螺旋-转角-螺旋结构的保守结构域。(3)启动子预测分析发现,光相关响应、赤霉素响应、脱落酸响应相关的顺式元件数量最多,其他元件如生长素响应、水杨酸响应、厌氧响应、昼夜节律响应、低温和防御响应等顺式元件不均匀分布于启动子中。(4)CsWOX4和CsWOX13a/CsWOX13b基因在根、茎、叶、花等组织均有较高的表达量; 并且与对照组相比,CsWOX4和CsWOX13a/CsWOX13b在干旱处理、钩状木霉处理及干旱和钩状木霉共处理的表达量发生变化,推测其可能在工业大麻生长发育以及植株抗逆过程中发挥潜在作用。该研究揭示其在生长发育和干旱胁迫响应中的分子功能,初步阐明钩状木霉通过调控WOX基因网络提升植株抗逆性的分子机制,为解析CsWOX基因家族在工业大麻生长发育及抗逆中的功能提供了重要线索。

Abstract:

Industrial hemp is an important fiber crop, and its fibers have multiple unique advantages and broad application prospects. WOX gene family has potential roles in regulating fiber development, plant growth, and stress resistance in industrial hemp. Currently, the functions of the CsWOX gene family in industrial hemp and its roles in key biological processes such as stable yield and yield increase have not been clarified. Therefore, this study used bioinformatics methods to analyze the physicochemical properties, conserved domains, and expression patterns of the CsWOX genes in industrial hemp, to reveal their molecular functions in fiber development and drought stress response, and to preliminarily clarify the molecular mechanism by which Trichoderma hamatum enhances plant stress resistance through regulating the WOX gene network. The results were as follows:(1)Eleven CsWOX gene family members were identified in industrial hemp, encoding proteins with number of amino acids ranging from 223 to 435 aa, and relative molecular weights ranging from 25 398.30 to 48 429.45 Da. Most proteins in this gene family were acidic and localized in the nucleus.(2)CsWOX proteins could be divided into three branches(ancient branch, intermediate branch, and modern branch). The modern branch contained six sub-branches, the intermediate branch contained two sub-branches, and the ancient branch contained only one sub-branch. WOX transcription factors in the same sub-branch had certain conservation in the types and organization of conserved motifs. Each family member contained a conserved domain with a helix-loop-helix-turn-helix structure.(3)Promoter prediction analysis found that the number of cis-elements related to light response, gibberellin response, and abscisic acid response was the highest. Other cis-elements such as auxin response, salicylic acid response, anaerobic response, circadian rhythm response, low temperature response, and defense response were unevenly distributed in the promoters.(4)CsWOX4 and CsWOX13a/CsWOX13b genes showed high expression levels in roots, stems, leaves, and flowers. Compared with the control group, the expression levels of CsWOX4 and CsWOX13a/CsWOX13b changed under drought treatment, Trichoderma hamatum treatment, and combined drought and Trichoderma hamatum treatment, suggesting that they may play potential roles in the growth, development, and stress resistance of industrial hemp. This study reveals the molecular functions of CsWOX genes in growth, development, and drought stress response, preliminarily clarifies the molecular mechanism by which Trichoderma hamatum enhances plant stress resistance through regulating the WOX gene network, and provides important clues for understanding the functions of the CsWOX gene family in the growth, development, and stress resistance of industrial hemp.