STIL, a peculiar molecule from styles, specifically dephosphorylates the pollen receptor kinase LePRK2 and stimulates pollen tube growth in vitro

• Autores: Wengier, D.L.; Mazzella, M.A.; Salem, T.M.; McCormick, S.; Muschietti, J.P.
• Año de publicación: 2010
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: BMC Plant Biol. 2010;10
• Materia: Lycopersicon esculentum; Nicotiana tabacum; protein kinase C; protein kinase N; vegetable protein; article; genetics; growth, development and aging; isolation and purification; metabolism; phosphorylation; pollen tube; tomato; Lycopersicon esculentum; Phosphorylation; Plant Proteins; Pollen Tube; Protein Kinase C
• Institución: Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales

Background: LePRK1 and LePRK2 are two pollen receptor kinases localized to the plasma membrane, where they are present in a high molecular weight complex (LePRK complex). LePRK2 is phosphorylated in mature and germinated pollen, but is dephosphorylated when pollen membranes are incubated with tomato or tobacco style extracts.Results: Here we show that LePRK2 dephosphorylation is mediated by a heat-, acid-, base-, DTT- and protease-resistant component from tobacco styles. Using LePRK2 phosphorylation as a tracking assay for purification, style exudates were subjected to chloroform extraction, anionic exchange, and C18 reverse-phase chromatography columns. We finally obtained a single ~3,550 Da compound (as determined by UV-MALDI-TOF MS) that we named STIL (for Style Interactor for LePRKs). STIL increased pollen tube lengths of in vitro germinated pollen in a dose-dependent manner.Conclusion: We propose that the LePRK complex perceives STIL, resulting in LePRK2 dephosphorylation and an increase in pollen tube growth. © 2010 Wengier et al; licensee BioMed Central Ltd.
Fil:Wengier, D.L. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Mazzella, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Salem, T.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Muschietti, J.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.