Potential role of Tctex-1 in the dendritic Golgi outpost transport mechanism

NASELLI A; QUASSOLLO G; GASTALDI L; CÁCERES A; CONDE C

Buenos Aires

Congreso; 5th ISN Special Conference; 2012

ISN

In mammalian and fly neurons, Golgi structures in the form of "outposts"(GOps) localize to dendrites and influence branching. Current evidence suggests that dynein is the motor that transports GOps in Drosophila neurons: disruption of the dynein/dynactin complex reduces the number of GOps and dendritic branches. It has been shown that Tctex-1, a dynein light chain, serves as an adaptor for rhodopsin transport; it localizes to the Golgi apparatus, where it interacts at least with G-beta-gamma and Lfc. Tctex-1 plays an important role in the development of neuronal polarity, including dendritic growth. Hence, Tctex-1, could be a good candidate to act as adaptor linking the dynein complex with GOps. Therefore, in this study we used cultured hippocampal neurons to analyze the consequences of the up- or down-regulation of Tctex-1 on the distribution and trafficking of dendritic GOps. Suppression of Tctex-1 reduces the number of GOps (around 50%) and alters their distribution, with most of the GOps accumulated in the inner third of major primary dendrites. By contrast, ectopic expression of Tctex-1 has the opposite effect, increasing the number of GOps distributed in higher order dendrites. Supported by ANPCyT and CONICET.