Abstract
Studies on UV-B-induced plant photomorphogenesis mainly focus on Arabidopsis shoots (hypocotyl, leaf, petiole, and stem) but less on roots. In the present research, the low-level UV-B (0.2 W·m-2) induced a decrease in the number of root cells in the meristem zone and an inhibition of the cell length in the maturation zone of roots in Arabidopsis thaliana L.Heynh (Col-0). UV-B-induced root growth inhibition was recovered by the addition of GA3 to culture media. GA3 played an important role in UV-B-induced inhibition of root growth. The cop1-4 mutant with more meristem cell and longer mature cells exhibited longer root length under low-level UV-B. COP1 acted as a positive regulator of root growth under UV-B, through regulation of cell division and elongation. The sto mutant exhibited a shorter root length under UV-B with similar cell length but fewer meristem cells compared with wild type (Col-0). STO only regulated cell division, but cell expansion was not affected. UV-B radiation also inhibited the root growth of uvr8 mutant, and the degree of inhibition was greater than for wild type (Ler). UV-B inhibited the growth of Arabidopsis root, possibly because it changes the GA signal and inhibited cell division and cell elongation, which be related to COP1 and STO genes.
Keywords:
Arabidopsis thaliana; COP1 gene; GA3; STO gene; UV-B radiation; photomorphogenesis.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Arabidopsis / drug effects
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Arabidopsis / genetics
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Arabidopsis / growth & development*
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Arabidopsis / radiation effects*
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Arabidopsis Proteins / genetics
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Arabidopsis Proteins / metabolism*
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Cell Division / drug effects
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Cell Division / radiation effects
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Chromosomal Proteins, Non-Histone / metabolism
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Gene Expression Regulation, Plant / drug effects
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Gene Expression Regulation, Plant / radiation effects
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Gibberellins / metabolism*
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Plant Growth Regulators / pharmacology
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Plant Roots / cytology
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Plant Roots / drug effects
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Plant Roots / growth & development*
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Plant Roots / radiation effects*
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Seedlings / drug effects
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Seedlings / growth & development
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Seedlings / radiation effects
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Ubiquitin-Protein Ligases / metabolism
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Ultraviolet Rays*
Substances
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Arabidopsis Proteins
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Chromosomal Proteins, Non-Histone
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Gibberellins
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Plant Growth Regulators
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STO protein, Arabidopsis
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Uvr8 protein, Arabidopsis
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gibberellic acid
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AT2G32950 protein, Arabidopsis
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Ubiquitin-Protein Ligases
Grants and funding
This work was supported by the National Natural Science Foundation of China [grant no. 31670266]; the Natural Science Foundation of Guangdong Province [grant no. 2017A030313115]; the Innovation Project of the Graduate School of South China Normal University [grant no. 2016lkxm10]; and the Leading Scientists Project of Guangdong Province, the Guangdong Pearl River Scholar Funded Scheme [2012].