title: Cell type-dependent axonal localization of translational regulators and mRNA in mouse peripheral olfactory neurons.
abstract: Local protein synthesis in mature axons may play a role in synaptic plasticity, axonal arborization, or functional diversity of the circuit. To gain insight into this question, we investigated the axonal localization of translational regulators and associated mRNAs in five parallel olfactory circuits, four in the main olfactory bulb and one in the accessory olfactory bulb. Axons in all four main olfactory bulb circuits exhibited axonal localization of Fragile X granules (FXGs), structures that comprise ribosomes, mRNA, and RNA binding proteins including Fragile X mental retardation protein (FMRP) and the related protein FXR2P. In contrast, FXGs were not seen in axons innervating the accessory olfactory bulb. Similarly, axons innervating the main olfactory bulb, but not the accessory olfactory bulb, contained the FXG-associated mRNA Omp (olfactory marker protein). This differential localization was not explained by circuit-dependent differences in expression of FXG components or Omp, suggesting that other factors must regulate their axonal transport. The specificity of this transport was highlighted by the absence from olfactory axons of the calmodulin transcript Calm1, which is highly expressed in peripheral olfactory neurons at levels equivalent to Omp. Regulation of axonal translation by FMRP may shape the structure and function of the axonal arbor in mature sensory neurons in the main olfactory system but not in the accessory olfactory system.
authors.affiliation: Department of Biology, Drexel University, Philadelphia, Pennsylvania, 19104.
authors.forename: Lulu I T
authors.initials: LIT
authors.lastname: Korsak
authors.affiliation: Department of Biology, Drexel University, Philadelphia, Pennsylvania, 19104.
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Shepard
authors.affiliation: Department of Biology, Drexel University, Philadelphia, Pennsylvania, 19104.|Department of Neurobiology and Anatomy, Drexel University, Philadelphia, Pennsylvania, 19104.
authors.forename: Michael R
authors.identifier: http://orcid.org/0000-0003-2420-2582
authors.initials: MR
authors.lastname: Akins
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism; D002147:Calmodulin / Q000235:genetics / Q000378:metabolism; D024402:Carbonic Anhydrase II / Q000235:genetics / Q000378:metabolism; D054678:Cyclic Nucleotide Phosphodiesterases, Type 2 / Q000235:genetics / Q000378:metabolism; D005260:Female; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D019006:Neural Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism; D009830:Olfactory Bulb / Q000166:cytology*; D051842:Olfactory Marker Protein / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D011984:Sensory Receptor Cells / Q000145:classification* / Q000378:metabolism*
chemical_list: C000595843:Calm1 protein, mouse; D002147:Calmodulin; C512309:FXR2 protein, mouse; C108768:Ncam2 protein, mouse; D019006:Neural Cell Adhesion Molecules; D051842:Olfactory Marker Protein; C497598:Omp protein, mouse; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D054678:Cyclic Nucleotide Phosphodiesterases, Type 2; C517277:Pde2a protein, mouse; D024402:Carbonic Anhydrase II
keywords: FXR2P; RRID: AB_2149710; RRID: AB_306884; RRID: AB_398856; RRID: AB_476964; RRID: AB_653928; RRID: AB_664696; olfactory epithelium; olfactory marker protein; olfactory sensory neuron; vomeronasal organ; vomeronasal sensory neuron