title: Nova2 regulates neuronal migration through an RNA switch in disabled-1 signaling.
abstract: Neuronal migration leads to a highly organized laminar structure in the mammalian brain, and its misregulation causes lissencephaly and behavioral and cognitive defects. Reelin signaling, which is mediated in part by a key adaptor, disabled-1 (Dab1), plays a critical but incompletely understood role in this process. We found that the neuron-specific RNA-binding protein Nova2 regulates neuronal migration in late-generated cortical and Purkinje neurons. An unbiased HITS-CLIP and exon junction array search for Nova-dependent reelin-pathway RNAs at E14.5 revealed only one candidate-an alternatively spliced isoform of Dab1 (Dab1.7bc). In utero electroporation demonstrated that Dab1.7bc was sufficient to induce neuronal migration defects in wild-type mice and exacerbate defects when Dab1 levels were reduced, whereas Dab1 overexpression mitigates defects in Nova2 null mice. Thus, Nova2 regulates an RNA switch controlling the ability of Dab1 to mediate neuronal responsiveness to reelin signaling and neuronal migration, suggesting new links between splicing regulation, brain disease, and development.
authors.affiliation: Laboratory of Molecular Neuro-Oncology and Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
authors.forename: Masato
authors.initials: M
authors.lastname: Yano
authors.forename: Yoshika
authors.initials: Y
authors.lastname: Hayakawa-Yano
authors.forename: Aldo
authors.initials: A
authors.lastname: Mele
authors.forename: Robert B
authors.initials: RB
authors.lastname: Darnell
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics / Q000502:physiology*; D001973:Bromodeoxyuridine / Q000378:metabolism; D002465:Cell Movement / Q000235:genetics*; D004622:Embryo, Mammalian; D051379:Mice; D018345:Mice, Knockout; D019579:Neocortex / Q000166:cytology*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D000090682:Neuro-Oncological Ventral Antigen; D009474:Neurons / Q000502:physiology*; D012326:RNA Splicing / Q000235:genetics*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D000091042:Reelin Protein; D015398:Signal Transduction / Q000235:genetics*
chemical_list: D000951:Antigens, Neoplasm; C103773:Dab1 protein, mouse; D009419:Nerve Tissue Proteins; D000090682:Neuro-Oncological Ventral Antigen; C515624:Nova2 protein, mouse; D016601:RNA-Binding Proteins; D000091042:Reelin Protein; C000717128:Reln protein, mouse; D001973:Bromodeoxyuridine