Plant Protection Research Institute and Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, P. R. China.
Key Laboratory of Agricultural Microbiology, College of Agriculture, Guizhou University, Guiyang, 550025, P. R. China.
J Nanobiotechnology. 2024 Nov 14;22(1):707. doi: 10.1186/s12951-024-02994-4.
Owing to their unique physiochemical properties, low toxicity, antipathogenic effects and tunability, fluorescent carbon quantum dots (CQDs) represent a new generation of carbon-based nanomaterials. Despite the mounting research on the efficacy of CQDs against resilient plant pathogens, their potential ability to mitigate viral pathogens and the underlying molecular mechanism(s) remain understudied. In this study, we optimized the CQDs to maximize their antiviral effects against a highly pathogenic Begomovirus (cotton leaf curl Multan virus, CLCuMuV) and elucidated the mechanistic pathways associated with CQDs-mediated viral inhibition. To fine-tune the CQDs-induced antiviral effects against CLCuMuV and investigate the underlying molecular mechanisms,we used HR-TEM, XRD, FT-IR, XPS, and UV‒Vis spectrophotometry to characterize the CQDs. SPAD and FluorCam were used for physiological and photosynthetic performance analysis. Transcriptome, RT‒qPCR, integrated bioinformatics and molecular biology were employed to investigate gene expression, viral quantification and data validation.
The application of fluorescent, hexagonal crystalline, UV-absorptive and water-soluble CQDs (0.01 mg/ml) significantly reduced the CLCuMuV titer and mitigated viral symptoms in N. benthamiana at the early (5 dpi) and late (20 dpi) stages of infection. CQDs significantly increased the morphophysiological properties, relative chlorophyll contents and photosynthetic (Fv/Fm, QY_max, NPQ and Rfd) performance of the CLCuMuV-infected plants. While CLCuMuV infection disrupted plant immunity, the CQDs improved the antiviral defense response by regulating important immunity-related genes involved in endocytosis/necroptosis, Tam3-transposase, the ABC transporter/sphingolipid signaling pathway and serine/threonine protein kinase activities. CQDs potentially triggered TSS and TTS alternative splicing events in CLCuMuV-infected plants.
Overall, these findings underscore the antiviral potential of CQDs, their impact on plant resilience, and their ability to modulate gene expression in response to viral stress. This study's molecular insights provide a foundation for further research on nanomaterial applications in plant virology and crop protection, emphasizing the promising role of CQDs in enhancing plant health and combating viral infections.
由于其独特的物理化学性质、低毒性、抗病原体作用和可调节性，荧光碳量子点 (CQD) 代表了新一代基于碳的纳米材料。尽管越来越多的研究关注 CQD 对有弹性的植物病原体的疗效，但它们减轻病毒病原体的潜在能力及其潜在的分子机制仍未得到充分研究。在这项研究中，我们优化了 CQD，以最大限度地提高其对高度致病性的 Begomovirus（棉花卷曲多斑病毒，CLCuMuV）的抗病毒作用，并阐明了与 CQD 介导的病毒抑制相关的机制途径。为了微调 CQD 对 CLCuMuV 的抗病毒作用并研究潜在的分子机制，我们使用高分辨率透射电子显微镜 (HR-TEM)、X 射线衍射 (XRD)、傅里叶变换红外光谱 (FT-IR)、X 射线光电子能谱 (XPS) 和紫外-可见分光光度法对 CQD 进行了表征。使用 SPAD 和 FluorCam 进行生理和光合作用性能分析。转录组、RT-qPCR、综合生物信息学和分子生物学被用于研究基因表达、病毒定量和数据验证。
应用荧光、六方晶、紫外吸收和水溶性 CQD（0.01 mg/ml）可显著降低 N. benthamiana 中的 CLCuMuV 滴度，并在感染的早期（5dpi）和晚期（20dpi）阶段减轻病毒症状。CQD 显著提高了 CLCuMuV 感染植物的形态生理特性、相对叶绿素含量和光合作用（Fv/Fm、QY_max、NPQ 和 Rfd）性能。虽然 CLCuMuV 感染破坏了植物免疫，但 CQD 通过调节内吞/坏死、Tam3-转座酶、ABC 转运体/鞘脂信号通路和丝氨酸/苏氨酸蛋白激酶活性等参与的重要免疫相关基因，改善了抗病毒防御反应。CQD 可能在 CLCuMuV 感染的植物中引发 TSS 和 TTS 可变剪接事件。
总体而言，这些发现强调了 CQD 的抗病毒潜力、它们对植物弹性的影响以及它们调节基因表达以应对病毒应激的能力。本研究的分子见解为纳米材料在植物病毒学和作物保护中的应用提供了进一步研究的基础，强调了 CQD 在增强植物健康和抵御病毒感染方面的有前途的作用。
