纳米银诱导拟南芥根细胞损伤与主根负向重力性生长的机制

王颖; 张传玲; 黄家权; 尹黎燕

doi:10.11913/PSJ.2095-0837.24080

纳米银诱导拟南芥根细胞损伤与主根负向重力性生长的机制

王颖^{1, 2,},
张传玲^{1, 2, ,},
黄家权³,
尹黎燕^{1, 2, ,}

1.
海南大学生命健康学院，海口 570228
2.
海南大学全健康研究院，海口 570228
3.
海南大学热带农林学院，海南三亚 572022

基金项目:

国家自然科学基金项目（31971520）；海南省重点研发项目（ZDYF2022SHFZ113）。

详细信息

作者简介:
王颖（1996−），女，硕士研究生，研究方向为纳米银毒理学（E-mail：2330964911@qq.com）

通讯作者:
张传玲: zcl@hainanu.edu.cn

尹黎燕: E-mail：lyyin@163.com

中图分类号: Q945
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出版历程
- 收稿日期: 2024-03-31
- 录用日期: 2024-05-22
- 刊出日期: 2025-04-29

Mechanism underlying silver nanoparticle induction of root cell damage and negative gravitropism in main roots of Arabidopsis thaliana (L.) Heynh.

Wang Ying^{1, 2,},
Zhang Chuanling^{1, 2, ,},
Huang Jiaquan³,
Yin Liyan^{1, 2, ,}

1.
School of Life and Health Sciences, Hainan University, Haikou 570228, China
2.
One Health Institute, Hainan University, Haikou 570228, China
3.
College of Breeding and Multiplication, Hainan University, Sanya, Hainan 572022, China

摘要

摘要:
本研究以拟南芥（Arabidopsis thaliana （L.） Heynh.）为材料，分析了纳米银（AgNPs）对根系生长、根细胞损伤和主根负向重力性的影响。结果显示：（1）30 mg/L AgNPs处理后，拟南芥根系中积累了大量Ag元素，显著高于0.12 mg/L Ag⁺（30 mg/L AgNPs中释放的Ag⁺浓度）处理组。（2）30 mg/L AgNPs显著抑制根毛数量和根毛长度，并抑制根毛细胞发育相关基因AtRHS12、AtRHS14、AtCOW1和AtMRH12的表达。（3）30 mg/L的AgNPs或Ag⁺均能显著诱导根系胼胝质的形成，并损伤根细胞，而0.12 mg/L Ag⁺处理后根系损伤不明显。（4）30 mg/L AgNPs导致拟南芥主根呈螺旋状生长，而30 mg/L及0.12 mg/L的Ag⁺则引发主根向左偏移。转录组测序及RT-qPCR分析结果表明，30 mg/L的 AgNPs或Ag⁺均显著下调乙烯调控相关基因的表达，并上调乙烯合成关键酶基因AtACS7的表达。研究结果表明，30 mg/L AgNPs抑制拟南芥根毛生长，诱导根细胞损伤，并可能通过乙烯信号通路调控根的弯曲生长，其毒性效应可能来源于纳米银本身的颗粒效应。
- 纳米银 /
- 根负向重力性 /
- 乙烯 /
- 拟南芥
Abstract:
This study explored the effects of silver nanoparticles (AgNPs) on root growth, cellular integrity, and negative gravitropism in Arabidopsis thaliana (L.) Heynh.. Results revealed that: (1) Treatment with 30 mg/L AgNPs led to a significant accumulation of Ag in roots, surpassing the levels observed in roots treated with 0.12 mg/L Ag⁺ (equivalent to the Ag⁺ released from 30 mg/L AgNPs). (2) Exposure to 30 mg/L AgNPs markedly inhibited the number and length of root hairs. Transcriptome sequencing and RT-qPCR analyses indicated that 30 mg/L AgNPs suppressed the expression of key genes associated with root hair cell development, including AtRHS12, AtRHS14, AtCOW1, and AtMRH12. (3) Both 30 mg/L AgNPs and 30 mg/L Ag⁺ induced root callus formation and caused significant root cell damage in A. thaliana. However, no significant root damage was observed in plants treated with 0.12 mg/L Ag⁺, suggesting that the Ag⁺ released from AgNPs was insufficient to cause cellular damage. (4) Exposure to 30 mg/L AgNPs induced a spiral growth pattern in the main root, contrasting with the leftward growth induced by 30 mg/L and 0.12 mg/L Ag⁺. Transcriptome sequencing and RT-qPCR analyses revealed that both 30 mg/L AgNPs and 30 mg/L Ag⁺ significantly down-regulated ethylene-regulated genes such as AtERS1, AtETR2, AtERF1, AtERF11, and AtEBP, while up-regulating the key ethylene synthesis gene AtACS7. These findings suggest that AgNPs and Ag⁺ may influence negative gravitropism in A. thaliana roots by modulating ethylene signaling pathways and ethylene biosynthesis. In conclusion, 30 mg/L AgNPs inhibit root hair growth, induce root cell damage, and influence gravitropic bending in A. thaliana roots through the ethylene signaling pathway. The observed toxic effects are likely attributable to the intrinsic properties of the nanoparticles.
- Silver nanoparticles /
- Root negative gravitropism /
- Ethylene /
- Arabidopsis thaliana
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图 1 AgNPs或Ag⁺处理6 d后叶片和根中银含量

1：CK；2：30 mg/L AgNPs；3：30 mg/L Ag⁺；4：0.12 mg/L Ag⁺。不同小写字母表示不同处理间差异显著（P<0.05），下同。

Figure 1. Silver content in Arabidopsis thaliana leaves and roots after six days of exposure to AgNPs or Ag⁺

1: CK; 2: 30 mg/L AgNPs; 3: 30 mg/L Ag⁺; 4: 0.12 mg/L Ag⁺. Different lowercase letters indicate significant differences at P<0.05 level between different treatments, same below.

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图 2 AgNPs或Ag⁺处理6 d后根系表型

Figure 2. Root phenotype of Arabidopsis thaliana after six days of exposure to AgNPs or Ag⁺

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图 3 AgNPs或 Ag⁺处理对拟南芥根系生长的影响

Figure 3. Effects of AgNPs or Ag⁺ treatments on taproot growth of Arabidopsis thaliana

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图 4 AgNPs或Ag⁺处理3 d对拟南芥根尖细胞活性的影响

A：碘化丙啶染色；B：苯胺蓝染色。

Figure 4. Propidium iodide (A) and aniline blue (B) staining to identify root apical cell activity in Arabidopsis thaliana after three days of exposure to AgNPs or Ag⁺

A: Propidium iodide; B: Aniline blue.

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图 5 AgNPs 或 Ag⁺（30 mg/L）处理6 d后拟南芥根RNA-seq数据的韦恩分析（A）和聚类分析（B）

Figure 5. Venn diagram (A) and agglomerative hierarchical clustering (B) of RNA-sequencing data in Arabidopsis thaliana roots after six days of exposure to AgNPs and Ag⁺ (30 mg/L)

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图 6 AgNPs或 Ag⁺处理6 d时根毛生长发育相关基因的表达

1：CK；2：30 mg/L Ag⁺；3：30 mg/L AgNPs。下同。

Figure 6. Effects of AgNPs or Ag⁺ on transcriptional levels of Arabidopsis thaliana root hair growth and development-related genes after six days of treatment

1: CK; 2: 30 mg/L Ag⁺; 3: 30 mg/L AgNPs. Same below.

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图 7 AgNPs 或 Ag⁺处理6 d 时根系中乙烯相关基因的表达

Figure 7. Effects of AgNPs or Ag⁺on transcription levels of ethylene-related genes in Arabidopsis thaliana roots after six days of treatment

下载: 全尺寸图片幻灯片

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