title: Regulation of Stomatal Defense by Air Relative Humidity.
abstract: It has long been observed that environmental conditions play crucial roles in modulating immunity and disease in plants and animals. For instance, many bacterial plant disease outbreaks occur after periods of high humidity and rain. A critical step in bacterial infection is entry into the plant interior through wounds and natural openings, such as stomata, which are adjustable microscopic pores in the epidermal tissue. Several studies have shown that stomatal closure is an integral part of the plant immune response to reduce pathogen invasion. In this study, we found that high humidity can effectively compromise Pseudomonas syringae-triggered stomatal closure in both Phaseolus vulgaris and Arabidopsis (Arabidopsis thaliana), which is accompanied by early up-regulation of the jasmonic acid (JA) pathway and simultaneous down-regulation of salicylic acid (SA) pathway in guard cells. Furthermore, SA-dependent response, but not JA-dependent response, is faster in guard cells than in whole leaves, suggesting that the SA signaling in guard cells may be independent from other cell types. Thus, we conclude that high humidity, a well-known disease-promoting environmental condition, acts in part by suppressing stomatal defense and is linked to hormone signaling in guard cells.
authors.affiliation: Department of Biology, University of Texas, Arlington, Texas 76019 (S.P., R.C., B.K.T., N.O., W.S.H.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (D.R., M.M.).
authors.forename: Shweta
authors.identifier: 0000-0003-4745-0976
authors.initials: S
authors.lastname: Panchal
authors.affiliation: Department of Biology, University of Texas, Arlington, Texas 76019 (S.P., R.C., B.K.T., N.O., W.S.H.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (D.R., M.M.).
authors.forename: Reejana
authors.initials: R
authors.lastname: Chitrakar
authors.affiliation: Department of Biology, University of Texas, Arlington, Texas 76019 (S.P., R.C., B.K.T., N.O., W.S.H.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (D.R., M.M.).
authors.forename: Blaine K
authors.initials: BK
authors.lastname: Thompson
authors.affiliation: Department of Biology, University of Texas, Arlington, Texas 76019 (S.P., R.C., B.K.T., N.O., W.S.H.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (D.R., M.M.).
authors.forename: Nisita
authors.initials: N
authors.lastname: Obulareddy
authors.affiliation: Department of Biology, University of Texas, Arlington, Texas 76019 (S.P., R.C., B.K.T., N.O., W.S.H.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (D.R., M.M.).
authors.forename: Debanjana
authors.identifier: 0000-0003-3885-1348
authors.initials: D
authors.lastname: Roy
authors.affiliation: Department of Biology, University of Texas, Arlington, Texas 76019 (S.P., R.C., B.K.T., N.O., W.S.H.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (D.R., M.M.).
authors.forename: W Sealy
authors.initials: WS
authors.lastname: Hambright
authors.affiliation: Department of Biology, University of Texas, Arlington, Texas 76019 (S.P., R.C., B.K.T., N.O., W.S.H.); and melotto@ucdavis.edu.|Department of Plant Sciences, University of California, Davis, California 95616 (D.R., M.M.) melotto@ucdavis.edu.
authors.forename: Maeli
authors.identifier: 0000-0001-6021-9803
authors.initials: M
authors.lastname: Melotto
mesh_terms: D000388:Air; D017360:Arabidopsis / Q000235:genetics / Q000382:microbiology / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003517:Cyclopentanes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D006813:Humidity; D054883:Oxylipins / Q000378:metabolism; D054046:Plant Stomata / Q000166:cytology / Q000502:physiology*; D044224:Pseudomonas syringae / Q000502:physiology; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D015854:Up-Regulation / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D054883:Oxylipins; C011006:jasmonic acid; D020156:Salicylic Acid