title: Distinct transcriptional profiles of ozone stress in soybean (Glycine max) flowers and pods.
abstract: BACKGROUND
  Tropospheric ozone (O3) is a secondary air pollutant and anthropogenic greenhouse gas. Concentrations of tropospheric O3 ([O3] have more than doubled since the Industrial Revolution, and are high enough to damage plant productivity. Soybean (Glycine max L. Merr.) is the world's most important legume crop and is sensitive to O3. Current ground-level [O3] are estimated to reduce global soybean yields by 6% to 16%. In order to understand transcriptional mechanisms of yield loss in soybean, we examined the transcriptome of soybean flower and pod tissues exposed to elevated [O3] using RNA-Sequencing.
  
  
  RESULTS
  Elevated [O3] elicited a strong transcriptional response in flower and pod tissues, with increased expression of genes involved in signaling in both tissues. Flower tissues also responded to elevated [O3] by increasing expression of genes encoding matrix metalloproteinases (MMPs). MMPs are zinc- and calcium-dependent endopeptidases that have roles in programmed cell death, senescence and stress response in plants. Pod tissues responded to elevated [O3] by increasing expression of xyloglucan endotransglucosylase/hydrolase genes, which may be involved with increased pod dehiscence in elevated [O3].
  
  
  CONCLUSIONS
  This study established that gene expression in reproductive tissues of soybean are impacted by elevated [O3], and flowers and pods have distinct transcriptomic responses to elevated [O3].
authors.affiliation: Department of Plant Biology, University of Illinois, Urbana-Champaign, Urbana, IL, 61801, USA. leisner1@illinois.edu.
authors.forename: Courtney P
authors.initials: CP
authors.lastname: Leisner
authors.affiliation: Department of Plant Biology, University of Illinois, Urbana-Champaign, Urbana, IL, 61801, USA. rming@life.illinois.edu.
authors.forename: Ray
authors.initials: R
authors.lastname: Ming
authors.affiliation: Department of Plant Biology, University of Illinois, Urbana-Champaign, Urbana, IL, 61801, USA. lisa.ainsworth@ars.usda.gov.|USDA ARS Global Change and Photosynthesis Research Unit, 1201 W. Gregory Drive, Urbana, IL, 61801, USA. lisa.ainsworth@ars.usda.gov.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Ainsworth
mesh_terms: D035264:Flowers / Q000187:drug effects* / Q000378:metabolism; D005638:Fruit / Q000187:drug effects* / Q000378:metabolism; D010126:Ozone / Q000633:toxicity*; D013025:Glycine max / Q000187:drug effects* / Q000378:metabolism; D013312:Stress, Physiological; D059467:Transcriptome / Q000187:drug effects*
chemical_list: D010126:Ozone