title: Radial derivatives of the mouse ventral pallium traced with Dbx1-LacZ reporters.
abstract: The progeny of Dbx1-expressing progenitors was studied in the developing mouse pallium, using two transgenic mouse lines: (1) Dbx1(nlslacZ) mice, in which the gene of the β-galactosidase reporter (LacZ) is inserted directly under the control of the Dbx1 promoter, allowing short-term lineage tracing of Dbx1-derived cells; and (2) Dbx1(CRE) mice crossed with a Cre-dependent reporter strain (ROSA26(loxP-stop-loxP-LacZ)), in which the Dbx1-derived cells result permanently labeled (Bielle et al., 2005). We thus examined in detail the derivatives of the postulated longitudinal ventral pallium (VPall) sector, which has been defined among other features by its selective ventricular zone expression of Dbx1 (the recent ascription by Puelles, 2014 of the whole olfactory cortex primordium to the VPall was tested). Earlier notions about a gradiental caudorostral reduction of Dbx1 signal were corroborated, so that virtually no signal was found at the olfactory bulb and the anterior olfactory area. The piriform cortex was increasingly labeled caudalwards. The only endopiriform grisea labeled were the ventral endopiriform nucleus and the bed nucleus of the external capsule. Anterior and basolateral parts of the whole pallial amygdala also were densely marked, in contrast to the negative posterior parts of these pallial amygdalar nuclei (leaving apart medial amygdalar parts ascribed to subpallial or extratelencephalic sources of Dbx1-derived GABAergic and non-GABAergic neurons). Alternative tentative interpretations are discussed to explain the partial labeling obtained of both olfactory and amygdaloid structures. This includes the hypothesis of an as yet undefined part of the pallium, potentially responsible for the posterior amygdala, or the hypothesis that the VPall may not be wholly characterized by Dbx1 expression (this gene not being necessary for VPall molecular distinctness and histogenetic potency), which would leave a dorsal Dbx1-negative VPall subdomain of variable size that might contribute partially to olfactory and posterior amygdalar structures.
authors.affiliation: Department of Human Anatomy and Psychobiology, Faculty of Medicine, University of Murcia, IMIB (Instituto Murciano de Investigación Biosanitaria), Murcia 30071, Spain. Electronic address: puelles@um.es.
authors.forename: Luis
authors.initials: L
authors.lastname: Puelles
authors.affiliation: Department of Human Anatomy and Psychobiology, Faculty of Medicine, University of Murcia, IMIB (Instituto Murciano de Investigación Biosanitaria), Murcia 30071, Spain.
authors.forename: Loreta
authors.initials: L
authors.lastname: Medina
authors.affiliation: Institut Jacques Monod, CNRS UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex, France.
authors.forename: Ugo
authors.initials: U
authors.lastname: Borello
authors.affiliation: Department of Human Anatomy and Psychobiology, Faculty of Medicine, University of Murcia, IMIB (Instituto Murciano de Investigación Biosanitaria), Murcia 30071, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Legaz
authors.affiliation: Institut Jacques Monod, CNRS UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex, France. Electronic address: anne.teissier@inserm.fr.
authors.forename: Anne
authors.initials: A
authors.lastname: Teissier
authors.affiliation: Institut Jacques Monod, CNRS UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex, France.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pierani
authors.affiliation: Nina Ireland Laboratory of Developmental Neurobiology, Department of Psychiatry, University of California at San Francisco, San Francisco, CA 94158, USA.
authors.forename: John L R
authors.initials: JL
authors.lastname: Rubenstein
mesh_terms: D000818:Animals; D066187:Basal Forebrain / Q000033:anatomy & histology*; D015415:Biomarkers / Q000032:analysis; D018398:Homeodomain Proteins / Q000032:analysis; D007763:Lac Operon; D051379:Mice; D008822:Mice, Transgenic; D058953:Neural Stem Cells / Q000166:cytology*; D055495:Neurogenesis
chemical_list: D015415:Biomarkers; C103403:Dbx1 protein, mouse; D018398:Homeodomain Proteins
keywords: Amygdala; Endopiriform nuclei; Entorhinal cortex; Hypothalamus; Lateral pallium; Pallial extended amygdala; Piriform cortex; Preoptic area; Ventral pallium