RESUMO
Alpha-Synuclein (aSyn) misfolding and aggregation is common in several neurodegenerative diseases, including Parkinson's disease and dementia with Lewy bodies, which are known as synucleinopathies. Accumulating evidence suggests that secretion and cell-to-cell trafficking of pathological forms of aSyn may explain the typical patterns of disease progression. However, the molecular mechanisms controlling aSyn aggregation and spreading of pathology are still elusive. In order to obtain unbiased information about the molecular regulators of aSyn oligomerization, we performed a microscopy-based large-scale RNAi screen in living cells. Interestingly, we identified nine Rab GTPase and kinase genes that modulated aSyn aggregation, toxicity and levels. From those, Rab8b, Rab11a, Rab13 and Slp5 were able to promote the clearance of aSyn inclusions and rescue aSyn induced toxicity. Furthermore, we found that endocytic recycling and secretion of aSyn was enhanced upon Rab11a and Rab13 expression in cells accumulating aSyn inclusions. Overall, our study resulted in the identification of new molecular players involved in the aggregation, toxicity, and secretion of aSyn, opening novel avenues for our understanding of the molecular basis of synucleinopathies.
Assuntos
Doença por Corpos de Lewy/genética , Doença de Parkinson/genética , Agregados Proteicos/genética , alfa-Sinucleína/genética , Proteínas rab de Ligação ao GTP/biossíntese , Proteína Quinase Tipo 1 Dependente de Cálcio-Calmodulina/genética , Proteínas de Transporte/genética , Linhagem Celular , Proteínas de Ligação a DNA/genética , Humanos , Proteínas de Membrana/genética , Proteínas Oncogênicas/genética , Dobramento de Proteína , Proteínas Serina-Treonina Quinases/genética , Transporte Proteico/genética , Proteínas Tirosina Quinases/genética , Interferência de RNA , RNA Interferente Pequeno/genética , alfa-Sinucleína/metabolismo , Proteínas rab de Ligação ao GTP/genética , Quinases DyrkRESUMO
Phospholipid-enveloped biodegradable polymer microparticles and nanoparticles synthesized by an emulsion/solvent evaporation process were characterized by confocal and cryoelectron microscopies to show that the lipid envelope exhibits two-dimensional fluidity and can be configured into 'shell', 'onion', or 'flower' nanostructures, depending on the quantity and composition of lipids employed in the synthesis.
