Watanabe Yuta, Ishiga Yasuhiro, Sakata Nanami
The Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan.
Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8572, Japan.
Microorganisms. 2025 Aug 1;13(8):1803. doi: 10.3390/microorganisms13081803.
Genomic islands (GIs) including integrative and conjugative elements (ICEs), prophages, and integrative plasmids are central drivers of horizontal gene transfer in bacterial plant pathogens. These elements often carry cargo genes encoding virulence factors, antibiotic and metal resistance determinants, and metabolic functions that enhance environmental adaptability. In plant-pathogenic species such as , GIs contribute to host specificity, immune evasion, and the emergence of novel pathogenic variants. ICE and its homologs represent integrative and mobilizable elements whose tightly regulated excision and transfer are driven by a specialized transcriptional cascade, while ICEs in highlight the ecological impact of cargo genes on pathogen virulence and fitness. Pathogenicity islands further modulate virulence gene expression in response to in planta stimuli. Beyond , GIs in genera such as , , and underpin critical traits like toxin biosynthesis, secretion system acquisition, and topoisomerase-mediated stability. Leveraging high-throughput genomics and structural biology will be essential to dissect GI regulation and develop targeted interventions to curb disease spread. This review synthesizes the current understanding of GIs in plant-pathogenic gammaproteobacteria and outlines future research priorities for translating mechanistic insights into sustainable disease control strategies.
基因组岛（GIs），包括整合性接合元件（ICEs）、前噬菌体和整合质粒，是细菌植物病原体水平基因转移的核心驱动因素。这些元件通常携带编码毒力因子、抗生素和金属抗性决定因素以及增强环境适应性的代谢功能的负载基因。在诸如 等植物致病物种中，基因组岛有助于宿主特异性、免疫逃避以及新型致病变体的出现。ICE及其同源物代表整合性可移动元件，其严格调控的切除和转移由专门的转录级联驱动，而 中的ICEs突出了负载基因对病原体毒力和适应性的生态影响。致病岛进一步响应植物体内刺激调节毒力基因表达。除了 ，诸如 、 和 等属中的基因组岛支撑着毒素生物合成、分泌系统获得和拓扑异构酶介导的稳定性等关键性状。利用高通量基因组学和结构生物学对于剖析基因组岛调控以及制定针对性干预措施以遏制疾病传播至关重要。本综述综合了目前对植物致病γ-变形菌中基因组岛的理解，并概述了将机制性见解转化为可持续疾病控制策略的未来研究重点。
