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PubMed · 17074884

Spatial codes in dendritic BC1 RNA.

Ilham A Muslimov·Anna Iacoangeli·Jürgen Brosius·Henri Tiedge
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Abstract

BC1 RNA is a dendritic untranslated RNA that has been implicated in local translational control mechanisms in neurons. Prerequisite for a functional role of the RNA in synaptodendritic domains is its targeted delivery along the dendritic extent. We report here that the targeting-competent 5' BC1 domain carries two dendritic targeting codes. One code, specifying somatic export, is located in the medial-basal region of the 5' BC1 stem-loop structure. It is defined by an export-determinant stem-bulge motif. The second code, specifying long-range dendritic delivery, is located in the apical part of the 5' stem-loop domain. This element features a GA kink-turn (KT) motif that is indispensable for distal targeting. It specifically interacts with heterogeneous nuclear ribonucleoprotein A2, a trans-acting targeting factor that has previously been implicated in the transport of MBP mRNA in oligodendrocytes and neurons. Our work suggests that a BC1 KT motif encodes distal targeting via the A2 pathway and that architectural RNA elements, such as KT motifs, may function as spatial codes in neural cells.

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5' Untranslated RegionsAnimalsBase SequenceCells, CulturedDendritesDrosophila ProteinsEmbryo, MammalianHeterogeneous-Nuclear Ribonucleoprotein Group A-BHomeodomain ProteinsMicroinjectionsMolecular Sequence DataMutationNucleic Acid ConformationProtein BindingRNARNA TransportRNA, Small CytoplasmicRatsRats, Sprague-DawleySuperior Cervical GanglionTrans-ActivatorsJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov't

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Ilham A Muslimov, Anna Iacoangeli, Jürgen Brosius, Henri Tiedge. 2006-10-30. Spatial codes in dendritic BC1 RNA.. https://doi.org/10.1083/jcb.200607008

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