title: In neurons, activity-dependent association of dendritically transported mRNA transcripts with the transacting factor CBF-A is mediated by A2RE/RTS elements.
abstract: In neurons certain mRNA transcripts are transported to synapses through mechanisms that are not fully understood. Here we report that the heterogeneous nuclear ribonucleoprotein CBF-A (CArG Box binding Factor A) facilitates dendritic transport and localization of activity-regulated cytoskeleton-associated protein (Arc), brain-derived neurotrophic factor (BDNF), and calmodulin-dependent protein kinase II (CaMKIIα) mRNAs. We discovered that, in the adult mouse brain, CBF-A has a broad distribution. In the nucleus, CBF-A was found at active transcription sites and interchromosomal spaces and close to nuclear pores. In the cytoplasm, CBF-A localized to dendrites as well as pre- and postsynaptic sites. CBF-A was found in synaptosomal fractions, associated with Arc, BDNF, and CaMKIIα mRNAs. Electrophoretic mobility shift assays demonstrated a direct interaction mediated via their hnRNP A2 response element (A2RE)/RNA trafficking sequence (RTS) elements located in the 3' untranslated regions. In situ hybridization and microscopy on live hippocampal neurons showed that CBF-A is in dynamic granules containing Arc, BDNF, and CaMKIIα mRNAs. N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) postsynaptic receptor stimulation led to CBF-A accumulation in dendrites; increased Arc, BDNF, and CaMKIIα mRNA levels; and increased amounts of transcripts coprecipitating with CBF-A. Finally, CBF-A gene knockdown led to decreased mRNA levels. We propose that CBF-A cotranscriptionally binds RTSs in Arc, BDNF, and CaMKIIα mRNAs and follows the transcripts from genes to dendrites, promoting activity-dependent nuclear sorting of transport-competent mRNAs.
authors.affiliation: Department of Cell and Molecular Biology, Karolinska Institutet, S-171 77 Stockholm, Sweden.
authors.forename: Chandrasekhar S
authors.initials: CS
authors.lastname: Raju
authors.forename: Nanaho
authors.initials: N
authors.lastname: Fukuda
authors.forename: Carmen
authors.initials: C
authors.lastname: López-Iglesias
authors.forename: Christian
authors.initials: C
authors.lastname: Göritz
authors.forename: Neus
authors.initials: N
authors.lastname: Visa
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Percipalle
mesh_terms: D020413:3' Untranslated Regions; D000818:Animals; D001369:Axons / Q000378:metabolism / Q000648:ultrastructure; D001483:Base Sequence; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics; D023081:CCAAT-Binding Factor / Q000235:genetics / Q000378:metabolism*; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000235:genetics; D018929:Cell Culture Techniques; D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D002478:Cells, Cultured; D003594:Cytoplasmic Granules / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000235:genetics; D003712:Dendrites / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics; D009474:Neurons / Q000378:metabolism*; D016548:Prosencephalon / Q000166:cytology / Q000378:metabolism; D011485:Protein Binding; D034622:RNA Interference; D034443:RNA Transport; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D020218:Response Elements / Q000235:genetics*; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D020413:3' Untranslated Regions; D019208:Brain-Derived Neurotrophic Factor; D023081:CCAAT-Binding Factor; D003598:Cytoskeletal Proteins; D008869:Microtubule-Associated Proteins; C079240:Mtap2 protein, mouse; D009419:Nerve Tissue Proteins; C492062:Nfyb protein, mouse; D012333:RNA, Messenger; C092069:activity regulated cytoskeletal-associated protein; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2