Lu Jing, Du Jinke, Tian Liying, Li Mengshuang, Zhang Xianchen, Zhang Shihua, Wan Xiaochun, Chen Qi
State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China.
College of Life Science and Health, University of Science and Technology, Wuhan, China.
Front Plant Sci. 2021 Nov 17;12:763843. doi: 10.3389/fpls.2021.763843. eCollection 2021.
In plants, the bZIP family plays vital roles in various biological processes, including seed maturation, flower development, light signal transduction, pathogen defense, and various stress responses. Tea, as a popular beverage, is widely cultivated and has withstood a degree of environmental adversity. Currently, knowledge of the bZIP gene family in tea plants remains very limited. In this study, a total of 76 genes in tea plant were identified for the whole genome. Phylogenetic analysis with counterparts revealed that CsbZIP proteins clustered into 13 subgroups, among which 13 ABFs related to the ABA signaling transduction pathway were further identified by conserved motif alignment and named CsABF1-13, these belonged to the A and S subgroups of CsbZIP and had close evolutionary relationships, possessing uniform or similar motif compositions. Transcriptome analysis revealed the expression profiles of genes in different tissues (bud, young leaf, mature leaf, old leaf, stem, root, flower, and fruit) and under diverse environmental stresses (drought, salt, chilling, and MeJA). Several genes with relatively low tissue expression, including , , , and , showed strong expression induction in stress response. Thirteen genes, were examined by qRT-PCR in two tea plant cultivars, drought-tolerant "Taicha 12" and drought-sensitive "Fuyun 6", under exogenous ABA and drought stress. Furthermore, , , and , were screened out as key transcription factors regulating drought tolerance of tea cultivars. Subsequently, some potential target genes regulated by CsABFs were screened by co-expression network and enrichment analysis. This study update CsbZIP gene family and provides a global survey of the ABF gene family in tea plant. The resolution of the molecular mechanism of drought resistance in different varieties could be helpful for improving stress resistance in tea plant via genetic engineering.
在植物中，bZIP家族在多种生物学过程中发挥着至关重要的作用，包括种子成熟、花发育、光信号转导、病原体防御以及各种应激反应。茶作为一种广受欢迎的饮品，被广泛种植且能耐受一定程度的环境逆境。目前，茶树中bZIP基因家族的知识仍然非常有限。在本研究中，从全基因组中鉴定出了茶树中的76个基因。与对应物的系统发育分析表明，CsbZIP蛋白聚为13个亚组，其中通过保守基序比对进一步鉴定出13个与ABA信号转导途径相关的ABF，并命名为CsABF1 - 13，它们属于CsbZIP的A和S亚组，具有密切的进化关系，拥有一致或相似的基序组成。转录组分析揭示了这些基因在不同组织（芽、幼叶、成熟叶、老叶、茎、根、花和果实）以及不同环境胁迫（干旱、盐、低温和茉莉酸甲酯）下的表达谱。几个组织表达相对较低的基因，包括[此处原文缺失具体基因名]，在应激反应中表现出强烈的表达诱导。通过qRT - PCR在两个茶树品种，耐旱的“苔茶12号”和干旱敏感的“福云6号”中，对外源ABA和干旱胁迫下的13个基因进行了检测。此外，[此处原文缺失具体基因名]被筛选为调节茶树品种耐旱性的关键转录因子。随后，通过共表达网络和富集分析筛选出了一些受CsABFs调控的潜在靶基因。本研究更新了CsbZIP基因家族，并对茶树中的ABF基因家族进行了全面的研究。解析不同品种抗旱的分子机制可能有助于通过基因工程提高茶树的抗逆性。
