IIB   20738
INSTITUTO DE INVESTIGACIONES BIOLOGICAS
Unidad Ejecutora - UE
artículos
Título:
Phosphatidylinositol 4-phosphate is associated to extracellular lipoproteic fractions and is detected in tomato apoplastic fluids.
Autor/es:
GONORAZKY, A. G.; LAXALT, A.; DEKKER, H; REP, M.; MUNNIK, T.; TESTERNIK, C.; DE LA CANAL, L.
Revista:
PLANT BIOLOGY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Año: 2011
ISSN:
1435-8603
Resumen:
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 to fractions composed by 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 been previously characterized 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 analyzed by 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 ionization tandem mass spectrometry (ESI-MS/MS) other phospholipids were found as well in intercellular fluids of tomato plants. These composed 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.