Phosphatidylinositol 4-phosphate is associated to extracellular lipoproteic fractions and is detected in tomato apoplastic fluids

We have recently detected phosphatidylinositol-4-phosphate (PI4P) in the extracellular medium of tomato cell suspensions. Extracellular PI4P was shown to trigger the activation of defence responses induced by the fungal elicitor xylanase. In this study, by applying a differential centrifugation tech...

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Detalhes bibliográficos
Autores: Gonorazky, Ana Gabriela, Laxalt, Ana Maria, Dekker, H. L., Rep, M., Munnik, T., Testerink, C., de la Canal, L
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/13122
Acesso em linha:http://hdl.handle.net/11336/13122
Access Level:acceso abierto
Palavra-chave:Apoplast
Extracellular Medium
Lipid Signalling
Lysophospholipid
Phosphatidic Acid
Phosphatidylinositol 4-Phosphate
Phosphoinositide
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descrição
Resumo:We have recently detected phosphatidylinositol-4-phosphate (PI4P) in the extracellular medium of tomato cell suspensions. Extracellular PI4P was shown to trigger the activation of defence responses induced by the fungal elicitor xylanase. In this study, by applying a differential centrifugation technique, we found that extracellular PI4P is associated with fractions composed of diverse phospholipids and proteins, which were pelleted from the extracellular medium of tomato cell suspensions grown under basal conditions. Using mass spectrometry, we identified the proteins present in these pelleted fractions. Most of these proteins have previously been characterised as having a role in defence responses. Next, we evaluated whether PI4P could also be detected in an entire plant system. For this, apoplastic fluids of tomato plants grown under basal conditions were analysed using a lipid overlay assay. Interestingly, PI4P could be detected in intercellular fluids obtained from tomato leaflets and xylem sap of tomato plants. By employing electrospray ionisation tandem mass spectrometry (ESI-MS/MS), other phospholipids were also found in intercellular fluids of tomato plants. These had a markedly different profile from the phospholipid pattern identified in entire leaflets. Based on these results, the potential role of extracellular phospholipids in plant intercellular communication is discussed.