Table_8_Systematic identification of TPS genes in Gossypium and their characteristics in response to flooding stress.xlsx

Terpene synthases (TPS) is a key enzyme in the synthesis of plant terpenoids. Studies on TPSs have not been reported in Gossypium barbadense and Gossypium arboreum. 260 TPSs were identified in Gossypium, including 71 in Gossypium hirsutum, 75 in Gossypium. barbadense, 60 in Gossypium. arboreum, and 54 in Gossypium raimondii. We systematically analyzed the TPS gene family of Gossypium from three aspects: gene structure, evolutionary process and gene function. (1) Gene structure: Based on the protein structure of two conserved domains (PF01397 and PF03936), the TPS gene family is divided into five clades: TPS -a, -b, -c, -e/f and -g. (2) Evolution: Whole genome duplication and segmental duplication are the main modes of TPS gene amplification. (3) Function: The abundance of cis-acting elements may reveal the functional diversity of TPSs in cotton. TPS gene has tissue specific expression in cotton. The hypomethylation of the exon of TPSs may help to enhance the adaptability of cotton to flooding stress. In conclusion, this study can broaden the understanding of structure-evolution-function of the TPS gene family, and provide reference for the mining and verification of new genes.

萜烯合酶（Terpene synthases, TPS）是植物萜类化合物合成过程中的关键酶。目前针对海岛棉（Gossypium barbadense）与亚洲棉（Gossypium arboreum）中的TPS相关研究尚未见报道。本研究在棉属中共鉴定出260个TPS基因，其中陆地棉（Gossypium hirsutum）含71个、海岛棉含75个、亚洲棉含60个、雷蒙德氏棉（Gossypium raimondii）含54个。本研究从基因结构、进化历程与基因功能三个维度，系统解析了棉属TPS基因家族：(1) 基因结构：基于两个保守结构域（PF01397与PF03936）的蛋白特征，TPS基因家族可划分为TPS-a、TPS-b、TPS-c、TPS-e/f及TPS-g共5个进化枝；(2) 进化机制：全基因组复制及片段重复是TPS基因家族扩增的主要方式；(3) 基因功能：顺式作用元件的丰富度可反映棉属TPS基因的功能多样性，TPS基因在棉花中呈现组织特异性表达模式，且TPS基因外显子区域的低甲基化或有助于提升棉花对渍水胁迫的适应性。综上，本研究有助于深化对TPS基因家族结构-进化-功能关联的认知，同时为新基因的挖掘与功能验证提供参考依据。