大豆GmNPRs基因家族的鉴定及表达分析

Identification and Expression Analysis of the GmNPRs Gene Family in Soybean

摘要: 病程相关基因非表达子(non-expressor of pathogenesis-related genes, NPR)是植物系统获得性抗性(SAR)中的核心调控因子，在水杨酸(SA)介导的抗病信号通路中发挥关键作用。然而，大豆(Glycine max)中NPR基因家族的系统性鉴定与功能特征尚不明确。本研究基于大豆基因组数据，利用生物信息学方法全面鉴定了GmNPRs基因家族成员，并对其基因结构、染色体分布、理化性质、保守结构域、系统发育关系、氨基酸序列相似性及组织表达模式进行了系统分析。结果表明，大豆基因组中共鉴定出8个GmNPRs基因，不均匀分布在6条染色体上，其编码蛋白具有典型的BTB/POZ、Ank repeat和NPR1_like_C等保守结构域，但结构域组成存在明显差异，提示功能分化。系统发育分析显示，GmNPRs成员在进化过程中呈现明显的遗传分化，且与拟南芥、水稻、玉米和番茄等物种的NPR基因存在不同程度的同源关系。基因结构分析揭示外显子–内含子数量与长度变异显著，可能与其功能多样性相关。组织表达分析表明，GmNPRs基因在不同组织中呈现明显的组织特异性表达模式，部分成员在花、叶、根瘤等组织中高表达，暗示其在生长发育与共生互作中可能具有重要调控功能。本研究系统解析了大豆GmNPRs基因家族的分子特征与表达规律，为深入探究其在抗病、抗逆及发育调控中的生物学功能提供了理论基础，也为大豆抗病遗传改良和分子育种提供了候选基因资源。

Abstract: The non-expressor of pathogenesis-related genes (NPR) family plays a central role in plant systemic acquired resistance (SAR), acting as a key regulator in salicylic acid (SA)-mediated defense signaling pathways. However, the comprehensive identification and functional characterization of the NPR gene family in soybean (Glycine max) remain largely unclear. In this study, we systematically identified the GmNPRs gene family members based on the soybean genome database using bioinformatics approaches, and conducted in-depth analyses of their gene structures, chromosomal distributions, physicochemical properties, conserved domains, phylogenetic relationships, amino acid sequence identities, and tissue-specific expression patterns. A total of eight GmNPRs genes were identified and unevenly distributed across six chromosomes. The encoded proteins contain typical conserved domains such as BTB/POZ, ankyrin repeats (Ank), and NPR1_like_C, although domain compositions vary significantly among members, suggesting potential functional divergence. Phylogenetic analysis revealed clear genetic differentiation among GmNPRs members, with varying degrees of homology to NPR genes from Arabidopsis thaliana, rice, maize, and tomato. Gene structure analysis showed substantial variation in the number and length of exons and introns, which may contribute to functional diversification. Tissue expression profiling indicated distinct spatial expression patterns, with certain members highly expressed in flowers, leaves, and nodules, implying potential roles in developmental regulation and symbiotic interactions. This study provides a comprehensive molecular characterization of the GmNPRs gene family in soybean, laying a solid foundation for further functional studies on their roles in disease resistance, stress response, and development. The results also offer valuable candidate genes for genetic improvement and molecular breeding of disease-resistant soybean varieties.