title: Spatial code recognition in neuronal RNA targeting: role of RNA-hnRNP A2 interactions.
abstract: In neurons, regulation of gene expression occurs in part through translational control at the synapse. A fundamental requirement for such local control is the targeted delivery of select neuronal mRNAs and regulatory RNAs to distal dendritic sites. The nature of spatial RNA destination codes, and the mechanism by which they are interpreted for dendritic delivery, remain poorly understood. We find here that in a key dendritic RNA transport pathway (exemplified by BC1 RNA, a dendritic regulatory RNA, and protein kinase M ζ [PKMζ] mRNA, a dendritic mRNA), noncanonical purine•purine nucleotide interactions are functional determinants of RNA targeting motifs. These motifs are specifically recognized by heterogeneous nuclear ribonucleoprotein A2 (hnRNP A2), a trans-acting factor required for dendritic delivery. Binding to hnRNP A2 and ensuing dendritic delivery are effectively competed by RNAs with CGG triplet repeat expansions. CGG repeats, when expanded in the 5' untranslated region of fragile X mental retardation 1 (FMR1) mRNA, cause fragile X-associated tremor/ataxia syndrome. The data suggest that cellular dysregulation observed in the presence of CGG repeat RNA may result from molecular competition in neuronal RNA transport pathways.
authors.affiliation: The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology and Pharmacology, State University of New York, Health Science Center at Brooklyn, USA.
authors.forename: Ilham A
authors.initials: IA
authors.lastname: Muslimov
authors.forename: Mihir V
authors.initials: MV
authors.lastname: Patel
authors.forename: Arthur
authors.initials: A
authors.lastname: Rose
authors.forename: Henri
authors.initials: H
authors.lastname: Tiedge
mesh_terms: D020121:5' Untranslated Regions; D000818:Animals; D042622:DNA Repeat Expansion; D003712:Dendrites / Q000235:genetics / Q000378:metabolism; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000235:genetics / Q000378:metabolism*; D005600:Fragile X Syndrome / Q000235:genetics; D005786:Gene Expression Regulation; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B / Q000235:genetics* / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D009690:Nucleic Acid Conformation; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020733:RNA, Small Cytoplasmic; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D020121:5' Untranslated Regions; D051860:Fragile X Messenger Ribonucleoprotein 1; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B; D012333:RNA, Messenger; D020733:RNA, Small Cytoplasmic; C117734:BC1 RNA; C439768:hnRNP A2