{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/33814"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/33814","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Dissecting Transcriptional Regulation of Rpp8 in Arabidopsis thaliana","abstract":"Plants have evolved physical barriers and inducible defense responses to combat microbial pathogens. Inducible responses are mediated by R proteins, which recognize invading pathogens. R proteins must be precisely regulated to provide effective resistance, without inhibiting normal plant growth. However, little is known about R gene regulation under defense-inducing conditions. The interaction between the oomycete Hyaloperonospora parasitica and the model plant Arabidopsis thaliana provides an excellent model system to explore R gene regulation. My research focuses on RPP8, a CC-NBS-LRR gene, which provides resistance to the H. parasitica isolate Emco5. Previous work in the McDowell lab suggested that RPP8 is upregulated during defense responses. My research shows that RPP8 alleles from the Columbia and Landsberg erecta ecotypes are upregulated by H. parasitica and the defense signaling molecule salicylic acid, suggesting a potential feedback loop. RPP8-Ler is also systemically upregulated after infection of the bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Additionally, RPP8-Ler expression is increased during wounding and heat stress. I also examined the role of regulatory cis elements in the RPP8 promoter. Three W-boxes are essential for basal and inducible RPP8 expression, and are required for resistance to Emco5. The X-box, a unique cis element in the RPP8 promoter, is essential for strong basal expression and wound-induced upregulation, and affects spatial expression of RPP8-Ler. However, the X-box is not required for RPP8-Ler upregulation during pathogen or SA treatment. R genes may be induced as part of global defense responses, which could prime the host for more effective pathogen recognition.","abstract_html":"Plants have evolved physical barriers and inducible defense responses to combat microbial pathogens. Inducible responses are mediated by R proteins, which recognize invading pathogens. R proteins must be precisely regulated to provide effective resistance, without inhibiting normal plant growth. However, little is known about R gene regulation under defense-inducing conditions. The interaction between the oomycete Hyaloperonospora parasitica and the model plant Arabidopsis thaliana provides an excellent model system to explore R gene regulation. My research focuses on RPP8, a CC-NBS-LRR gene, which provides resistance to the H. parasitica isolate Emco5. Previous work in the McDowell lab suggested that RPP8 is upregulated during defense responses. My research shows that RPP8 alleles from the Columbia and Landsberg erecta ecotypes are upregulated by H. parasitica and the defense signaling molecule salicylic acid, suggesting a potential feedback loop. RPP8-Ler is also systemically upregulated after infection of the bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Additionally, RPP8-Ler expression is increased during wounding and heat stress. I also examined the role of regulatory cis elements in the RPP8 promoter. Three W-boxes are essential for basal and inducible RPP8 expression, and are required for resistance to Emco5. The X-box, a unique cis element in the RPP8 promoter, is essential for strong basal expression and wound-induced upregulation, and affects spatial expression of RPP8-Ler. However, the X-box is not required for RPP8-Ler upregulation during pathogen or SA treatment. R genes may be induced as part of global defense responses, which could prime the host for more effective pathogen recognition.","abstract_has_math":false,"creators":["Mohr, Toni Jolene"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Plant Pathology, Physiology, and Weed Science","degree_department":"Plant Pathology, Physiology, and Weed Science","school":null,"contributors":[],"advisors":[],"committee_chairs":["McDowell, John M."],"committee_members":["Jelesko, John G.","Nessler, Craig L."],"year":2005,"date_issued":"2005-06-15","date_published":"2005-06-15","updated_at":"2026-07-22T22:19:38Z","subjects":["Arabidopsis thaliana","RPP8","Hyaloperonospora parasitica","R gene","disease"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-06292005-140540"],"render_values":[{"text":"etd-06292005-140540","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/33814","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["McDowell, John M."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Jelesko, John G.","Nessler, Craig L."]},{"key":"dc:contributor.department","label":"Department","values":["Plant Pathology, Physiology, and Weed Science"]},{"key":"dc:creator","label":"Author","values":["Mohr, Toni Jolene"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T20:40:50Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T20:40:50Z","2008-07-15"]},{"key":"dc:date.issued","label":"Date","values":["2005-06-15"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Plant Pathology, Physiology, and Weed Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Arabidopsis thaliana","RPP8","Hyaloperonospora parasitica","R gene","disease"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-06292005-140540"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/33814"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Plants have evolved physical barriers and inducible defense responses to combat microbial pathogens. Inducible responses are mediated by R proteins, which recognize invading pathogens. R proteins must be precisely regulated to provide effective resistance, without inhibiting normal plant growth. However, little is known about R gene regulation under defense-inducing conditions. The interaction between the oomycete Hyaloperonospora parasitica and the model plant Arabidopsis thaliana provides an excellent model system to explore R gene regulation. My research focuses on RPP8, a CC-NBS-LRR gene, which provides resistance to the H. parasitica isolate Emco5. Previous work in the McDowell lab suggested that RPP8 is upregulated during defense responses. My research shows that RPP8 alleles from the Columbia and Landsberg erecta ecotypes are upregulated by H. parasitica and the defense signaling molecule salicylic acid, suggesting a potential feedback loop. RPP8-Ler is also systemically upregulated after infection of the bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Additionally, RPP8-Ler expression is increased during wounding and heat stress. I also examined the role of regulatory cis elements in the RPP8 promoter. Three W-boxes are essential for basal and inducible RPP8 expression, and are required for resistance to Emco5. The X-box, a unique cis element in the RPP8 promoter, is essential for strong basal expression and wound-induced upregulation, and affects spatial expression of RPP8-Ler. However, the X-box is not required for RPP8-Ler upregulation during pathogen or SA treatment. R genes may be induced as part of global defense responses, which could prime the host for more effective pathogen recognition."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:title","label":"Title","values":["Dissecting Transcriptional Regulation of Rpp8 in Arabidopsis thaliana"]}]}],"canonical_facts":{"dc:contributor.committeechair":["McDowell, John M."],"dc:contributor.committeemember":["Jelesko, John G.","Nessler, Craig L."],"dc:contributor.department":["Plant Pathology, Physiology, and Weed Science"],"dc:creator":["Mohr, Toni Jolene"],"dc:date.accessioned":["2014-03-14T20:40:50Z"],"dc:date.available":["2014-03-14T20:40:50Z","2008-07-15"],"dc:date.issued":["2005-06-15"],"dc:description.abstract":["Plants have evolved physical barriers and inducible defense responses to combat microbial pathogens. Inducible responses are mediated by R proteins, which recognize invading pathogens. R proteins must be precisely regulated to provide effective resistance, without inhibiting normal plant growth. However, little is known about R gene regulation under defense-inducing conditions. The interaction between the oomycete Hyaloperonospora parasitica and the model plant Arabidopsis thaliana provides an excellent model system to explore R gene regulation. My research focuses on RPP8, a CC-NBS-LRR gene, which provides resistance to the H. parasitica isolate Emco5. Previous work in the McDowell lab suggested that RPP8 is upregulated during defense responses. My research shows that RPP8 alleles from the Columbia and Landsberg erecta ecotypes are upregulated by H. parasitica and the defense signaling molecule salicylic acid, suggesting a potential feedback loop. RPP8-Ler is also systemically upregulated after infection of the bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Additionally, RPP8-Ler expression is increased during wounding and heat stress. I also examined the role of regulatory cis elements in the RPP8 promoter. Three W-boxes are essential for basal and inducible RPP8 expression, and are required for resistance to Emco5. The X-box, a unique cis element in the RPP8 promoter, is essential for strong basal expression and wound-induced upregulation, and affects spatial expression of RPP8-Ler. However, the X-box is not required for RPP8-Ler upregulation during pathogen or SA treatment. R genes may be induced as part of global defense responses, which could prime the host for more effective pathogen recognition."],"dc:description.degree":["Master of Science"],"dc:identifier.other":["etd-06292005-140540"],"dc:identifier.uri":["http://hdl.handle.net/10919/33814"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["Arabidopsis thaliana","RPP8","Hyaloperonospora parasitica","R gene","disease"],"dc:title":["Dissecting Transcriptional Regulation of Rpp8 in Arabidopsis thaliana"],"dc:type":["Thesis"],"thesis:degree_discipline":["Plant Pathology, Physiology, and Weed Science"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:38Z"}