AutoriPicco, Cristiana; Scholz-Starke, Joachim; Festa, Margherita; Costa, Alex; Sparla, Francesca; Trost, Paolo; Carpaneto, Armando
AbstractTrans-plasma membrane electron transfer is achieved by b-type cytochromes of different families, and plays a fundamental role in diverse cellular processes involving two interacting redox couples that are physically separated by a phospholipid bilayer, such as iron uptake and redox signaling. Despite their importance, no direct recordings of trans-plasma membrane electron currents have been described in plants. In this work, we provide robust electrophysiological evidence of trans-plasma membrane electron flow mediated by a soybean (Glycine max) cytochrome b561 associated with a dopamine beta-monooxygenase redox domain (CYBDOM), which localizes to the plasma membrane in transgenic Arabidopsis (Arabidopsis thaliana) plants and CYBDOM complementary RNA-injected Xenopus laevis oocytes. In oocytes, two-electrode voltage clamp experiments showed that CYBDOM-mediated currents were activated by extracellular electron acceptors in a concentration- and type-specific manner. Current amplitudes were voltage dependent, strongly potentiated in oocytes preinjected with ascorbate (the canonical electron donor for cytochrome b561), and abolished by mutating a highly conserved His residue (H292L) predicted to coordinate the cytoplasmic heme b group. We believe that this unique approach opens new perspectives in plant transmembrane electron transport and beyond.
RivistaPlant Physiology (bethesda)
Impact factor0
Pagina inizio986
Pagina fine95
Autori IBFArmando CARPANETO, Cristiana PICCO, Joachim Johannes SCHOLZ STARKE, Margherita FESTA
Linee di Ricerca IBFMD.P01.001.001