title: The segmental organization of the developing shark brain based on neurochemical markers, with special attention to the prosencephalon.
abstract: Brain regionalization has been extensively studied in tetrapods, teleosts and cyclostomes. In contrast, it has not been investigated in elasmobranchs, despite their key phylogenetic position to understand brain evolution in jawed vertebrates. In this study we provide a schematic view of the segmental pattern of the developing shark brain based on mapping of the expression of Pax6 and neurochemical markers such as calretinin, tyrosine hydroxylase, serotonin, and glutamic acid decarboxylase. By correlating the cytoarchitectonic limits with the specific location of these markers, we identify transverse and longitudinal boundaries and domains, which suggest a segmental pattern, reminiscent of the one described in other vertebrates. Taken together, these data provide an initial scheme, which will be further tested and refined using a broader range of genetic markers involved in patterning and differentiation.
authors.affiliation: Department of Cell Biology and Ecology, University of Santiago de Compostela, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Ferreiro-Galve
authors.forename: Iván
authors.initials: I
authors.lastname: Carrera
authors.forename: Eva
authors.initials: E
authors.lastname: Candal
authors.forename: Begoña
authors.initials: B
authors.lastname: Villar-Cheda
authors.forename: Ramón
authors.initials: R
authors.lastname: Anadón
authors.forename: Sylvie
authors.initials: S
authors.lastname: Mazan
authors.forename: Isabel
authors.initials: I
authors.lastname: Rodríguez-Moldes
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D015415:Biomarkers / Q000378:metabolism*; D001921:Brain / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D064032:Calbindin 2; D004625:Embryo, Nonmammalian; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D005968:Glutamate Decarboxylase / Q000235:genetics / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D064030:S100 Calcium Binding Protein G / Q000235:genetics / Q000378:metabolism; D012701:Serotonin / Q000235:genetics / Q000378:metabolism; D012754:Sharks / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D064032:Calbindin 2; D005136:Eye Proteins; D018398:Homeodomain Proteins; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D012097:Repressor Proteins; D064030:S100 Calcium Binding Protein G; D012701:Serotonin; D014446:Tyrosine 3-Monooxygenase; D005968:Glutamate Decarboxylase