水稻OsGCD基因家族鉴定与非生物胁迫表达谱分析

Identification of OsGCD gene family in rice and analysis of its expression profiles under abiotic stress

关键词:  水稻,OsGCD基因家族, 非生物胁迫, 鞘脂代谢, 生物信息学

Key words:  rice, OsGCD gene family, abiotic stress, sphingolipid metabolism, bioinformatics

摘要:

水稻(Oryza sativa)是全球重要的粮食作物,其产量常因盐、碱、干旱等非生物胁迫而受到严重影响。葡萄糖神经酰胺酶(glucosylceramide enzyme, GCD)作为鞘脂代谢通路的关键酶,在植物非生物胁迫响应中的分子机制尚未阐明,并且目前缺乏系统性的生物信息学研究。该研究采用全基因组分析方法,在水稻中鉴定出 4 个OsGCD基因家族成员(OsGCD1-OsGCD4),通过整合生物信息学分析和实验验证手段,系统解析了该基因家族的分子特征、进化关系及表达调控模式,旨在揭示其在植物非生物逆境胁迫应答中的生物学功能。结果表明:(1)生物信息学分析显示,这些成员均含有保守的 DUF608 结构域,并且其启动子区域富含干旱响应元件(MBS)及激素响应元件(ABRE/GARE)。(2)组织表达谱分析表明,OsGCD1 优势表达于三叶期的根; OsGCD2 高表达于萌芽期、根及蜡熟期籽粒中; OsGCD3 在萌芽期、三叶期的茎和叶及孕穗期花序中表达量均较高; OsGCD4 在各阶段茎中持续高表达。(3)qRT-PCR 分析进一步揭示,OsGCD1和OsGCD4在叶片中受盐、碱和干旱胁迫诱导时,表现出快速且强烈的表达上调,表明它们可能在胁迫初期的快速响应中发挥关键作用。相比之下,OsGCD2则展现出独特的根系优势表达模式,尤其是在胁迫后期,其在根系中的表达量显著高于叶片。该研究阐明了OsGCD基因家族通过时空特异性表达模式参与水稻逆境适应的分子机制,为抗逆育种提供了新的靶点。

Abstract:

Rice(Oryza sativa)is a globally important food crop, and its yield is often severely affected by abiotic stresses such as salinity and drought. Glucosylceramide enzyme(GCD), as a key enzyme in the sphingolipid metabolic pathway, its molecular mechanism in response to abiotic stress in plants has not been clarified, and there is currently a lack of systematic bioinformatics research. In this study, a genome-wide analysis method was used to identify four OsGCD gene family members(OsGCD1-OsGCD4)in rice. Through the integration of bioinformatics analysis and experimental verification methods, the molecular characteristics, evolutionary relationships, and expression regulation patterns of this gene family were systematically analyzed, aiming to reveal its biological functions in response to abiotic stress in plants. The results were as follows:(1)Bioinformatics analyses revealed that all OsGCD members contained a conserved DUF608 domain and possessed promoter regions enriched with drought-responsive(MBS)and hormone-responsive(ABRE/GARE)cis-elements.(2)Tissue expression profiling analysis indicated that OsGCD1 was predominantly expressed in roots at the three-leaf stage; OsGCD2 was highly expressed in roots at the germination stage and in grains at the wax ripening stage; OsGCD3 had high expression levels in stems and leaves at the three-leaf stage and in inflorescences at the booting stage; OsGCD4 was continuously highly expressed in stems at all stages.(3)Quantitative real-time PCR(qRT-PCR)analysis revealed that OsGCD1 and OsGCD4 exhibited a rapid and strong upregulation in leaves under salt, alkali, and drought stress conditions, suggesting their potential role in early stress response regulation. In contrast, OsGCD2 displayed a distinct root-predominant expression pattern, particularly during later stress stages, with significantly higher expression levels in roots compared to leaves. This study elucidates the OsGCD gene family's molecular mechanisms in rice stress adaptation through spatiotemporal expression patterns, offering novel targets for stress-resistant crop breeding.