Local translation of dendritic RhoA revealed by an improved synaptoneurosome preparation.
Changes in dendritic spine morphology, a hallmark of synaptic plasticity, involve remodeling of the actin cytoskeleton, a process that is regulated by Rho GTPases. RhoA, a member of this GTPase family, segregates to dendrites in differentiated neurons. Given the emerging role of dendritic mRNA local translation in synaptic plasticity, we have assessed the possible localization and translation of RhoA mRNA at dendrites. At this end, we have developed and describe here in detail an improved method for isolating hippocampal and neocortical mouse synaptoneurosomes. This synaptoneurosomal preparation is much more enriched in synaptic proteins than those obtained in former methods, exhibits bona fide electron microscopy pre- and postsynaptic morphologies, contains abundant dendritic mRNAs, and is competent for activity-regulated protein synthesis. Using this preparation, we have found that RhoA mRNA is dendritically localized and its local translation is enhanced by BDNF stimulation. These findings suggest that some of the known functions of RhoA on spine morphology may be mediated by regulating its local translation.
Troca-Marín
José A
JA
Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, E-41009 Sevilla, Spain.
Alves-Sampaio
Alexandra
A
Tejedor
Francisco J
FJ
Montesinos
María Luz
ML
D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D003712:Dendrites / Q000378:metabolism* / Q000648:ultrastructure; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D014176:Protein Biosynthesis; D013574:Synaptosomes / Q000737:chemistry* / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000235:genetics / Q000378:metabolism*
D019208:Brain-Derived Neurotrophic Factor; D020742:rhoA GTP-Binding Protein