Rüter Philipp, Debener Thomas, Winkelmann Traud
Institute of Horticultural Production Systems, Section Woody Plant and Propagation Physiology, Leibniz University Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany.
Institute of Plant Genetics, Section Molecular Plant Breeding, Leibniz University Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany.
Plant Cell Rep. 2024 Dec 3;43(12):300. doi: 10.1007/s00299-024-03388-4.
Multiple QTLs reveal the polygenic nature of R. rhizogenes-mediated transformation and hairy root formation in roses, with five key regions explaining 12.0-26.9% of trait variability and transformation-related candidate genes identified. Understanding genetic mechanisms of plant transformation remains crucial for biotechnology. This is particularly relevant for roses and other woody ornamentals that exhibit recalcitrant behavior in transformation procedures. Rhizobium rhizogenes-mediated transformation leading to hairy root (HR) formation provides an excellent model system to study transformation processes and host-pathogen interactions. Therefore, this study aimed to identify quantitative trait loci (QTLs) associated with HR formation and explore their relationship with adventitious root (AR) formation in rose as a model for woody ornamentals. A diversity panel of 104 in vitro grown rose genotypes was transformed with R. rhizogenes strain ATCC 15834 carrying a green fluorescent protein reporter gene. Phenotypic data on callus and root formation were collected for laminae and petioles. A genome-wide association study using 23,419 single-nucleotide polymorphism markers revealed significant QTLs on chromosomes one and two for root formation traits. Five key genomic regions explained 12.0-26.9% of trait variability, with some peaks overlapping previously reported QTLs for AR formation. This genetic overlap was supported by weak to moderate correlations between HR and AR formation traits, particularly in petioles. Candidate gene identification through literature review and transcriptomic data analysis revealed ten candidate genes involved in bacterial response, hormone signaling, and stress responses. Our findings provide new insights into the genetic control of HR formation in roses and highlight potential targets for improving transformation efficiency in ornamental crops, thereby facilitating future research and breeding applications.
多个数量性状基因座揭示了发根农杆菌介导的玫瑰转化和毛状根形成的多基因性质，五个关键区域解释了性状变异的12.0-26.9%，并鉴定了与转化相关的候选基因。了解植物转化的遗传机制对生物技术仍然至关重要。这对于在转化过程中表现出顽固行为的玫瑰和其他木本观赏植物尤为重要。发根农杆菌介导的导致毛状根（HR）形成的转化提供了一个研究转化过程和宿主-病原体相互作用的优秀模型系统。因此，本研究旨在鉴定与玫瑰中HR形成相关的数量性状基因座（QTL），并探索它们与不定根（AR）形成的关系，以作为木本观赏植物的模型。用携带绿色荧光蛋白报告基因的发根农杆菌菌株ATCC 15834转化了104个体外培养的玫瑰基因型的多样性群体。收集了叶片和叶柄上愈伤组织和根形成的表型数据。使用23419个单核苷酸多态性标记进行的全基因组关联研究揭示了染色体1和2上与根形成性状相关的显著QTL。五个关键基因组区域解释了性状变异的12.0-26.9%，一些峰值与先前报道的AR形成QTL重叠。HR和AR形成性状之间弱至中等的相关性支持了这种遗传重叠，特别是在叶柄中。通过文献综述和转录组数据分析进行的候选基因鉴定揭示了10个参与细菌反应、激素信号传导和应激反应的候选基因。我们的研究结果为玫瑰中HR形成的遗传控制提供了新的见解，并突出了提高观赏作物转化效率的潜在靶点，从而促进未来的研究和育种应用。
