Dendritic LSm1/CBP80-mRNPs mark the early steps of transport commitment and translational control |
| |
| Authors: | Alessandra di Penta Valentina Mercaldo Fulvio Florenzano Sebastian Munck M. Teresa Ciotti Francesca Zalfa Delio Mercanti Marco Molinari Claudia Bagni Tilmann Achsel |
| |
| Affiliation: | 1.Ludwig Institute for Cancer Research, 2.Department of Medicine, 3.Department of Cellular and Molecular Medicine, and 4.Cancer Center, University of California, San Diego School of Medicine, La Jolla, CA 92093;5.Centre National de la Recherche Scientifique Unité Mixte de Recherche 2027, Institut Curie, Centre Universitaire, 91405 Orsay, France |
| |
| Abstract: | Messenger RNA (mRNA) transport to neuronal dendrites is crucial for synaptic plasticity, but little is known of assembly or translational regulation of dendritic messenger ribonucleoproteins (mRNPs). Here we characterize a novel mRNP complex that is found in neuronal dendrites throughout the central nervous system and in some axonal processes of the spinal cord. The complex is characterized by the LSm1 protein, which so far has been implicated in mRNA degradation in nonneuronal cells. In brain, it associates with intact mRNAs. Interestingly, the LSm1-mRNPs contain the cap-binding protein CBP80 that associates with (pre)mRNAs in the nucleus, suggesting that the dendritic LSm1 complex has been assembled in the nucleus. In support of this notion, neuronal LSm1 is partially nuclear and inhibition of mRNA synthesis increases its nuclear localization. Importantly, CBP80 is also present in the dendrites and both LSm1 and CBP80 shift significantly into the spines upon stimulation of glutamergic receptors, suggesting that these mRNPs are translationally activated and contribute to the regulated local protein synthesis. |
| |
| Keywords: | |
|
|
