title: Hydrogen peroxide, nitric oxide and UV RESISTANCE LOCUS8 interact to mediate UV-B-induced anthocyanin biosynthesis in radish sprouts.
abstract: The cross talk among hydrogen peroxide (H2O2), nitric oxide (NO) and UV RESISTANCE LOCUS8 (UVR8) in UV-B-induced anthocyanin accumulation in the hypocotyls of radish sprouts was investigated. The results showed that UV-B irradiation significantly increased the anthocyanin accumulation and the expression of UVR8, and a similar trend appeared in radish sprouts subjected to cadmium, chilling and salt stresses regardless of light source. However, these responses disappeared under dark exposure. These results suggest that abiotic stress-induced anthocyanin accumulation and UVR8 expression were light-dependent. Moreover, abiotic stresses all enhanced the production of H2O2 and exogenous H2O2 addition significantly increased the anthocyanin concentration and UVR8 transcription, while these increases were severely inhibited by addition of dimethylthiourea (DMTU, a chemical trap for H2O2). It seems to suggest that H2O2 played an important role in the anthocyanin biosynthesis. Furthermore, addition of 0.5 mM sodium nitroprusside (SNP, a NO-releasing compound) substantially induced the anthocyanin accumulation, and H2O2-induced anthocyanin accumulation and UVR8 expression were significantly suppressed by co-treatment with 2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl (PTIO, a NO scavenger), which was parallel with the expression of anthocyanin biosynthesis-related transcription factors and structural genes. All these results demonstrate that both H2O2 and NO are involved in UV-B-induced anthocyanin accumulation, and there is a crosstalk between them as well as a classical UVR8 pathway.
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wu
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China.
authors.forename: Nana
authors.initials: N
authors.lastname: Su
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China.
authors.forename: Jin
authors.initials: J
authors.lastname: Cui
authors.affiliation: Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental &Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Yongchao
authors.initials: Y
authors.lastname: Liang
mesh_terms: D000872:Anthocyanins / Q000096:biosynthesis* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics; D019607:Brassicaceae / Q000254:growth & development; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics; D003497:Cyclic N-Oxides / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D007093:Imidazoles / Q000494:pharmacology; D009569:Nitric Oxide / Q000235:genetics* / Q000378:metabolism; D031224:Raphanus / Q000235:genetics / Q000254:growth & development; D036226:Seedlings / Q000235:genetics* / Q000254:growth & development / Q000528:radiation effects; D015398:Signal Transduction / Q000528:radiation effects; D013312:Stress, Physiological / Q000187:drug effects / Q000528:radiation effects; D014157:Transcription Factors / Q000235:genetics*; D014466:Ultraviolet Rays
chemical_list: D000872:Anthocyanins; D029681:Arabidopsis Proteins; D002868:Chromosomal Proteins, Non-Histone; D003497:Cyclic N-Oxides; D007093:Imidazoles; D014157:Transcription Factors; C525052:Uvr8 protein, Arabidopsis; C079391:2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide; D009569:Nitric Oxide; D006861:Hydrogen Peroxide