title: RNA-seq analysis reveals the role of red light in resistance against Pseudomonas syringae pv. tomato DC3000 in tomato plants.
abstract: BACKGROUND
  Plants attenuate their responses to a variety of bacterial and fungal pathogens, leading to higher incidences of pathogen infection at night. However, little is known about the molecular mechanism responsible for the light-induced defence response; transcriptome data would likely facilitate the elucidation of this mechanism.
  
  
  RESULTS
  In this study, we observed diurnal changes in tomato resistance to Pseudomonas syringae pv. tomato DC3000 (Pto DC3000), with the greatest susceptibility before midnight. Nightly light treatment, particularly red light treatment, significantly enhanced the resistance; this effect was correlated with increased salicylic acid (SA) accumulation and defence-related gene transcription. RNA-seq analysis revealed that red light induced a set of circadian rhythm-related genes involved in the phytochrome and SA-regulated resistance response. The biosynthesis and signalling pathways of multiple plant hormones (auxin, SA, jasmonate, and ethylene) were co-ordinately regulated following Pto DC3000 infection and red light, and the SA pathway was most significantly affected by red light and Pto DC3000 infection. This result indicates that SA-mediated signalling pathways are involved in red light-induced resistance to pathogens. Importantly, silencing of nonexpressor of pathogensis-related genes 1 (NPR1) partially compromised red light-induced resistance against Pto DC3000. Furthermore, sets of genes involved in redox homeostasis (respiratory burst oxidase homologue, RBOH; glutathione S-transferases, GSTs; glycosyltransferase, GTs), calcium (calmodulin, CAM; calmodulin-binding protein, CBP), and defence (polyphenol oxidase, PPO; nudix hydrolase1, NUDX1) as well as transcription factors (WRKY18, WRKY53, WRKY60, WRKY70) and cellulose synthase were differentially induced at the transcriptional level by red light in response to pathogen challenge.
  
  
  CONCLUSIONS
  Taken together, our results suggest that there is a diurnal change in susceptibility to Pto DC3000 with greatest susceptibility in the evening. The red light induced-resistance to Pto DC3000 at night is associated with enhancement of the SA pathway, cellulose synthase, and reduced redox homeostasis.
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, P. R. China. yangyouxinchina@163.com.|Key Laboratory of Horticultural Plants Growth, Development and Quality Improvement, Agricultural Ministry of China, Zijingang Road 866, Hangzhou, 310058, P. R. China. yangyouxinchina@163.com.
authors.forename: You-Xin
authors.initials: YX
authors.lastname: Yang
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, P. R. China. mengmeng.wang@philips.com.|Philips Research China, No. 9 Lane 888 Tian Lin Road, Shanghai, 200233, P. R. China. mengmeng.wang@philips.com.
authors.forename: Meng-Meng
authors.initials: MM
authors.lastname: Wang
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, P. R. China. yinyanling@zju.edu.cn.|Key Laboratory of Horticultural Plants Growth, Development and Quality Improvement, Agricultural Ministry of China, Zijingang Road 866, Hangzhou, 310058, P. R. China. yinyanling@zju.edu.cn.
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Yin
authors.affiliation: Philips Research Europe, High Tech Campus 34, 5656 AE, Eindhoven, Netherlands. eugen.onac@philips.com.
authors.forename: Eugen
authors.initials: E
authors.lastname: Onac
authors.affiliation: Philips Research Europe, High Tech Campus 34, 5656 AE, Eindhoven, Netherlands. guofu.zhou@philips.com.
authors.forename: Guo-Fu
authors.initials: GF
authors.lastname: Zhou
authors.affiliation: Philips Research China, No. 9 Lane 888 Tian Lin Road, Shanghai, 200233, P. R. China. sheng.peng@philips.com.
authors.forename: Sheng
authors.initials: S
authors.lastname: Peng
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, P. R. China. xiaojianxia@zju.edu.cn.
authors.forename: Xiao-Jian
authors.initials: XJ
authors.lastname: Xia
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, P. R. China. kaishi@zju.edu.cn.
authors.forename: Kai
authors.initials: K
authors.lastname: Shi
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, P. R. China. jqyu@zju.edu.cn.|Key Laboratory of Horticultural Plants Growth, Development and Quality Improvement, Agricultural Ministry of China, Zijingang Road 866, Hangzhou, 310058, P. R. China. jqyu@zju.edu.cn.
authors.forename: Jing-Quan
authors.initials: JQ
authors.lastname: Yu
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, P. R. China. yanhongzhou@zju.edu.cn.|Key Laboratory of Horticultural Plants Growth, Development and Quality Improvement, Agricultural Ministry of China, Zijingang Road 866, Hangzhou, 310058, P. R. China. yanhongzhou@zju.edu.cn.
authors.forename: Yan-Hong
authors.initials: YH
authors.lastname: Zhou
mesh_terms: D002940:Circadian Rhythm / Q000235:genetics; D060467:Disease Resistance / Q000235:genetics; D017343:Genes, Plant; D005978:Glutathione / Q000378:metabolism; D008027:Light; D018551:Solanum lycopersicum / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects; D033902:Periplasmic Binding Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010788:Photosynthesis / Q000235:genetics; D010935:Plant Diseases / Q000382:microbiology / Q000517:prevention & control; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D044224:Pseudomonas syringae / Q000254:growth & development / Q000472:pathogenicity*; D012313:RNA / Q000737:chemistry / Q000302:isolation & purification; D020156:Salicylic Acid / Q000032:analysis; D017423:Sequence Analysis, RNA; D015398:Signal Transduction / Q000235:genetics; D014158:Transcription, Genetic; D059467:Transcriptome
chemical_list: D033902:Periplasmic Binding Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D012313:RNA; D005978:Glutathione; D020156:Salicylic Acid