title: Global transcriptome profiling analysis reveals insight into saliva-responsive genes in alfalfa.
abstract: We studied the genome-wide multiple time-course transcriptome dynamics after saliva deposition in alfalfa and demonstrate that saliva deposition functions as a stress that negatively affects the regrowth of alfalfa. Saliva deposition is one of the key factors influencing plant-herbivore interactions during grazing. Although many studies have focused on the effects of saliva deposition on plant regrowth, no consistent conclusions have been reached. Alfalfa is the most extensively cultivated forage legume, yet most alfalfa cultivars, thus far, are not grazing-tolerant. To better understand the underlying mechanism, we undertook a study to evaluate the global changes in the transcriptome of alfalfa after cow saliva deposition treatment. In this study, cDNA libraries from alfalfa seedlings at 0, 4, 8, and 24 h after cow saliva deposition were constructed and sequenced, resulting in the identification of 53,195 annotated unigenes, from which 4,814 unigenes were significantly differentially expressed. A metabolic pathway enrichment analysis demonstrated that saliva deposition functions as a stress that negatively affects the regrowth of alfalfa by modifying jasmonic acid synthesis, enhancing the susceptibility to pathogens and reducing the expression levels of ribosomal protein genes. In the present study, we demonstrate the potential effects of saliva deposition on alfalfa regrowth at the transcriptome level. These fundamental and important findings could facilitate further investigations into the molecular mechanisms underlying the responses of alfalfa and other related species to herbivore grazing.
authors.affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.
authors.forename: Wenxian
authors.initials: W
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.
authors.forename: Zhengshe
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, The Chinese Academy of Sciences, Beijing, China.
authors.forename: Shuangyan
authors.initials: S
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.
authors.forename: Lichao
authors.initials: L
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.
authors.forename: Hucheng
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.
authors.forename: Yanrong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China. lzp@lzu.edu.cn.
authors.forename: Zhipeng
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D063990:Gene Ontology; D060434:Herbivory / Q000502:physiology; D000455:Medicago sativa / Q000235:genetics*; D053858:Metabolic Networks and Pathways / Q000235:genetics; D058977:Molecular Sequence Annotation; D018515:Plant Leaves / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012463:Saliva / Q000737:chemistry / Q000502:physiology*; D017422:Sequence Analysis, DNA / Q000379:methods
keywords: Alfalfa; Differentially expressed genes; Next-generation sequencing; Saliva deposition; Transcriptomes