RESUMEN

Local control of mRNA translation modulates neuronal development, synaptic plasticity, and memory formation. A poorly understood aspect of this control is the role and composition of ribonucleoprotein (RNP) particles that mediate transport and translation of neuronal RNAs. Here, we show that staufen- and FMRP-containing RNPs in Drosophila neurons contain proteins also present in somatic "P bodies," including the RNA-degradative enzymes Dcp1p and Xrn1p/Pacman and crucial components of miRNA (argonaute), NMD (Upf1p), and general translational repression (Dhh1p/Me31B) pathways. Drosophila Me31B is shown to participate (1) with an FMRP-associated, P body protein (Scd6p/trailer hitch) in FMRP-driven, argonaute-dependent translational repression in developing eye imaginal discs; (2) in dendritic elaboration of larval sensory neurons; and (3) in bantam miRNA-mediated translational repression in wing imaginal discs. These results argue for a conserved mechanism of translational control critical to neuronal function and open up new experimental avenues for understanding the regulation of mRNA function within neurons.

Asunto(s)

Proteínas de Drosophila/fisiología , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Neuronas/metabolismo , Proteínas de Unión al ARN/metabolismo , Ribonucleoproteínas/fisiología , Animales , Animales Modificados Genéticamente , Northern Blotting , Western Blotting/métodos , Caspasas/metabolismo , Células Cultivadas , Sistema Nervioso Central/citología , Dendritas/metabolismo , Dendritas/fisiología , Drosophila , Proteínas de Drosophila/metabolismo , Exorribonucleasas/metabolismo , Ojo/metabolismo , Ojo/ultraestructura , Proteínas Fluorescentes Verdes/metabolismo , Inmunohistoquímica/métodos , Larva , MicroARNs/metabolismo , Microscopía Electrónica de Rastreo/métodos , Neuronas/citología , Biosíntesis de Proteínas/fisiología , Transporte de Proteínas/fisiología , Complejo Silenciador Inducido por ARN/metabolismo