tailieunhanh - Báo cáo khoa học: Puroindoline-a and a1-purothionin form ion channels in giant liposomes but exert different toxic actions on murine cells

Puroindoline-a (PIN-a) anda1-purothionin (a1-PTH), isolated from wheat endosperm ofTriticum aestivumsp., have been suggested to play a role in plant defence mechanisms against phytopathogenic organisms. We investi-gated their ability to form pores when incorporated into giant liposomes using the patch-clamp technique. | iFEBS Journal Puroindoline-a and a1-purothionin form ion channels in giant liposomes but exert different toxic actions on murine cells Paola Llanos1 Mauricio Henriquez1 Jasmina Minic2 Khalil Elmorjani3 Didier Marion3 Gloria Riquelme1 Jordi Molgo2 and Evelyne Benoit2 1 Institute de Ciencias Biomedicas Facultad de Medicina Universidad de Chile Santiago Chile 2 Laboratoire de Neurobiologie Cellulaire et Moleculaire UPR 9040 Centre Nationalde la Recherche Scientifique Gif-sur-Yvette cedex France 3 Biopolymeres Interactions Assemblages Institut Nationalde la Recherche Agronomique Nantes France Keywords a1-purothionin giant liposomes ion channels neuromuscular transmission puroindoline-a Correspondence E. Benoit Laboratoire de Neurobiologie Cellulaire et Moleculaire UPR 9040 Centre Nationalde la Recherche Scientifique bat. 32-33 91198 Gif-sur-Yvette cedex France Fax 33 169 82 41 41 Tel 33 169 82 36 52 E-mail benoit@ Received 20 July 2005 revised 13 February 2006 accepted 17 February 2006 doi Puroindoline-a PIN-a and a1-purothionin a1-PTH isolated from wheat endosperm of Triticum aestivum sp. have been suggested to play a role in plant defence mechanisms against phytopathogenic organisms. We investigated their ability to form pores when incorporated into giant liposomes using the patch-clamp technique. PIN-a formed cationic channels 15 pS with the following selectivity K Na o Cl-. Also a1-PTH formed channels of w 46 pS and 125 pS at 100 mV the selectivity of which was Ca2 Na w K o Cl- and Cl- Na respectively. In isolated mouse neuromuscular preparations a1-PTH induced muscle membrane depolarization leading to blockade of synaptic transmission and directly elicited muscle twitches. Also a1-PTH caused swelling of differentiated neuroblastoma NG108-15 cells membrane bleb formation and disorganization of F-actin. In contrast similar concentrations of PIN-a had no detectable effects. The cytotoxic actions of a1-PTH on mammalian

• Báo cáo khoa học
• Report medicine
• traditional medicine
• scientific reports