Transcriptome analysis reveals key roles of AtLBR-2 in LPS-induced defense responses in plants

BMC Genomics

Research Article

Sayaka Iizasa¹  Yukio Nagano²  Keiichi Watanabe³  Ei’ichi Iizasa⁴ 

[1] Analytical Research Center for Experimental Sciences, Saga University, Saga, Japan;Department of Biological Resource Sciences, Graduate School of Agriculture, Saga University, Saga, Japan;Department of Biological Science and Technology, The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan;Analytical Research Center for Experimental Sciences, Saga University, Saga, Japan;Department of Biological Science and Technology, The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan;Department of Biological Resource Sciences, Graduate School of Agriculture, Saga University, Saga, Japan;Department of Biological Science and Technology, The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan;Department of Immunology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan;

关键词: Plant immunity;    Defense response;    Lipopolysaccharide;    RNA-Seq;    Arabidopsis;    Salicylic acid;   

DOI  :  10.1186/s12864-017-4372-4

 received in 2017-03-14, accepted in 2017-12-08,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundLipopolysaccharide (LPS) from Gram-negative bacteria cause innate immune responses in animals and plants. The molecules involved in LPS signaling in animals are well studied, whereas those in plants are not yet as well documented. Recently, we identified Arabidopsis AtLBR-2, which binds to LPS from Pseudomonas aeruginosa (pLPS) directly and regulates pLPS-induced defense responses, such as pathogenesis-related 1 (PR1) expression and reactive oxygen species (ROS) production. In this study, we investigated the pLPS-induced transcriptomic changes in wild-type (WT) and the atlbr-2 mutant Arabidopsis plants using RNA-Seq technology.ResultsRNA-Seq data analysis revealed that pLPS treatment significantly altered the expression of 2139 genes, with 605 up-regulated and 1534 down-regulated genes in WT. Gene ontology (GO) analysis on these genes showed that GO terms, “response to bacterium”, “response to salicylic acid (SA) stimulus”, and “response to abscisic acid (ABA) stimulus” were enriched amongst only in up-regulated genes, as compared to the genes that were down-regulated. Comparative analysis of differentially expressed genes between WT and the atlbr-2 mutant revealed that 65 genes were up-regulated in WT but not in the atlbr-2 after pLPS treatment. Furthermore, GO analysis on these 65 genes demonstrated their importance for the enrichment of several defense-related GO terms, including “response to bacterium”, “response to SA stimulus”, and “response to ABA stimulus”. We also found reduced levels of pLPS-induced conjugated SA glucoside (SAG) accumulation in atlbr-2 mutants, and no differences were observed in the gene expression levels in SA-treated WT and the atlbr-2 mutants.ConclusionThese 65 AtLBR-2-dependent up-regulated genes appear to be important for the enrichment of some defense-related GO terms. Moreover, AtLBR-2 might be a key molecule that is indispensable for the up-regulation of defense-related genes and for SA signaling pathway, which is involved in defense against pathogens containing LPS.

【 授权许可】

CC BY   
© The Author(s). 2017