title: Rubber particle proteins, HbREF and HbSRPP, show different interactions with model membranes.
abstract: The biomembrane surrounding rubber particles from the hevea latex is well known for its content of numerous allergen proteins. HbREF (Hevb1) and HbSRPP (Hevb3) are major components, linked on rubber particles, and they have been shown to be involved in rubber synthesis or quality (mass regulation), but their exact function is still to be determined. In this study we highlighted the different modes of interactions of both recombinant proteins with various membrane models (lipid monolayers, liposomes or supported bilayers, and multilamellar vesicles) to mimic the latex particle membrane. We combined various biophysical methods (polarization-modulation-infrared reflection-adsorption spectroscopy (PM-IRRAS)/ellipsometry, attenuated-total reflectance Fourier-transform infrared (ATR-FTIR), solid-state nuclear magnetic resonance (NMR), plasmon waveguide resonance (PWR), fluorescence spectroscopy) to elucidate their interactions. Small rubber particle protein (SRPP) shows less affinity than rubber elongation factor (REF) for the membranes but displays a kind of "covering" effect on the lipid headgroups without disturbing the membrane integrity. Its structure is conserved in the presence of lipids. Contrarily, REF demonstrates higher membrane affinity with changes in its aggregation properties, the amyloid nature of REF, which we previously reported, is not favored in the presence of lipids. REF binds and inserts into membranes. The membrane integrity is highly perturbed, and we suspect that REF is even able to remove lipids from the membrane leading to the formation of mixed micelles. These two homologous proteins show affinity to all membrane models tested but neatly differ in their interacting features. This could imply differential roles on the surface of rubber particles.
authors.affiliation: CNRS, LCPO, UMR 5629, F-33600 Pessac, France; Univ. Bordeaux, LCPO, UMR 5629, F-33600 Pessac, France. Electronic address: kberthelot@enscbp.fr.
authors.forename: Karine
authors.initials: K
authors.lastname: Berthelot
authors.forename: Sophie
authors.initials: S
authors.lastname: Lecomte
authors.forename: Yannick
authors.initials: Y
authors.lastname: Estevez
authors.forename: Vanessa
authors.initials: V
authors.lastname: Zhendre
authors.forename: Sarah
authors.initials: S
authors.lastname: Henry
authors.forename: Julie
authors.initials: J
authors.lastname: Thévenot
authors.forename: Erick J
authors.initials: EJ
authors.lastname: Dufourc
authors.forename: Isabel D
authors.initials: ID
authors.lastname: Alves
authors.forename: Frédéric
authors.initials: F
authors.lastname: Peruch
mesh_terms: D000485:Allergens / Q000737:chemistry; D052179:Antigens, Plant / Q000737:chemistry*; D028482:Hevea / Q000737:chemistry; D007840:Latex / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010940:Plant Proteins / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry; D012408:Rubber / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D020349:Surface Plasmon Resonance
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D007840:Latex; D008051:Lipid Bilayers; D008081:Liposomes; D010940:Plant Proteins; D011994:Recombinant Proteins; C119716:SRPP protein, Hevea brasiliensis; C061477:REF protein, Hevea brasiliensis; D012408:Rubber
keywords: ATR-FTIR; Amyloid; Attenuated-total reflectance Fourier-transform infrared; Hevea brasiliensis latex; LUV; Large unilamellar vesicle; MLV; Multi lamellar vesicle; NMR; Natural rubber; Nuclear magnetic resonance; PM-IRRAS; PWR; Plant membrane; Plasmon waveguide resonance; Polarization-modulation-infrared reflection-adsorption spectroscopy; REF; Rubber elongation factor; SRPP; SUV; Small rubber particle protein; Small unilamellar vesicle