1. Glomerular podocytes contain neuron-like functional synaptic vesicles
- Author
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Maria Pia Rastaldi, Silvia Armelloni, Silvia Berra, Novella Calvaresi, Alessandro Corbelli, Laura Anna Giardino, Min Li, Guo Quin Wang, Alessandro Fornasieri, Antonello Villa, Eija Heikkila, Rabah Soliymani, Anissa Boucherot, Clemens David Cohen, Matthias Kretzler, Almut Nitsche, Maddalena Ripamonti, Antonio Malgaroli, Marzia Pesaresi, Gian Luigi Forloni, Detlef Schlöndorff, Harry Holthofer, Giuseppe D'Amico, Rastaldi, M, Armelloni, S, Berra, S, Calvaresi, N, Corbelli, A, Giardino, L, Li, M, Wang, G, Fornasieri, A, Villa, A, Heikkila, E, Soliymani, R, Boucherot, A, Cohen, C, Kretzler, M, Nitsche, A, Ripamonti, M, Malgaroli, A, Pesaresi, M, Forloni, G, Schlöndorff, D, Holthofer, H, D'Amico, G, Rastaldi, Mp, Giardino, La, Wang, Gq, Cohen, Cd, Malgaroli, Antonio, Forloni, Gl, and D'Amico, G.
- Subjects
Synaptic Vesicle ,Glutamic Acid ,Spider Venoms ,Biology ,Biochemistry ,Synaptic vesicle ,Synaptotagmin 1 ,Exocytosis ,Exocytosi ,Synapse ,Mice ,Genetics ,medicine ,Animals ,Humans ,Molecular Biology ,Cells, Cultured ,Endocytosi ,Animal ,Podocytes ,Glomerular basement membrane ,Gene Expression Profiling ,Synaptotagmin I ,Rab3A GTP-Binding Protein ,Endocytosis ,rab3A GTP-Binding Protein ,Cell biology ,medicine.anatomical_structure ,Gene Expression Regulation ,Glomerular Filtration Barrier ,Synaptic Vesicles ,Spider Venom ,Human ,Biotechnology - Abstract
Although patients with chronic renal failure are increasing worldwide, many aspects of kidney biology remain to be elucidated. Recent research has uncovered several molecular properties of the glomerular filtration barrier, in which podocytes, highly differentiated, ramified cells that enwrap the glomerular basement membrane, have been reported to be mainly responsible for filter's selectivity. We previously described that podocytes express Rab3A, a GTPase restricted to cell types that are capable of highly regulated exocytosis, such as neuronal cells. Here, we first demonstrate by a proteomic study that Rab3A in podocytes coimmmunoprecipitates with molecules once thought to be synapse specific. We then show that podocytes possess structures resembling synaptic vesicles, which contain glutamate, coexpress Rab3A and synaptotagmin 1, and undergo spontaneous and stimulated exocytosis and recycling, with glutamate release. Finally, from the results of a cDNA microarray study, we describe the presence of a series of neuron- and synapse-specific molecules in normal human glomeruli and confirm the glomerular protein expression of both metabotropic and ionotropic glutamate receptors. These data point toward a synaptic-like mechanism of communication among glomerular cells, which perfectly fits with the molecular composition of the glomerular filter and puts in perspective several previous observations, proposing a different working hypothesis for understanding glomerular signaling dynamics.
- Published
- 2006