title: Centrosomal aggregates and Golgi fragmentation disrupt vesicular trafficking of DAT.
abstract: Lewy bodies containing the centrosomal protein γ-tubulin and fragmentation of Golgi apparatus (GA) have been described in nigral neurons of Parkinson's disease (PD) patients. However, the relevance of these features in PD pathophysiology remains unknown. We analyzed the impact of proteasome inhibition in the formation of γ-tubulin-containing aggregates as well as on GA structure. SH-SY5Y cells were treated with the proteasome inhibitor Z-Leu-Leu-Leu-al (MG132) to induce centrosomal-protein aggregates. Then, microtubules (MTs) and Golgi dynamics, as well as the vesicular transport of dopamine transporter (DAT) were evaluated both in vitro and in living cells. MG132 treatment induced γ-tubulin aggregates which altered microtubule nucleation. MG132-treated cells containing γ-tubulin aggregates showed fragmentation of GA and perturbation of the trans-Golgi network. Under these conditions, the DAT accumulated at the centrosomal-Golgi region indicating that the vesicular transport of DAT was disrupted. Thus, centrosomal aggregates and fragmentation of GA are 2 closely related processes that could result in the disruption of the vesicular transport of DAT toward the plasma membrane in a model of dopaminergic neuronal degeneration.
authors.affiliation: Departamento de Señalización Celular, Centro Andaluz de Biología Molecular y Medicina Regenerativa, Seville, Spain. francisco.diaz@cabimer.es
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Diaz-Corrales
authors.forename: Ikuko
authors.initials: I
authors.lastname: Miyazaki
authors.forename: Masato
authors.initials: M
authors.lastname: Asanuma
authors.forename: Diego
authors.initials: D
authors.lastname: Ruano
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Rios
mesh_terms: D001692:Biological Transport / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D018385:Centrosome / Q000187:drug effects / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D006056:Golgi Apparatus / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D007976:Leupeptins / Q000494:pharmacology; D008870:Microtubules / Q000378:metabolism; D061988:Proteasome Inhibitors / Q000494:pharmacology; D014404:Tubulin / Q000378:metabolism
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D007976:Leupeptins; D061988:Proteasome Inhibitors; C493214:SLC6A3 protein, human; D014404:Tubulin; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde