title: Role of the Otx1 gene in cell differentiation of mammalian cortex.
abstract: This study analyses by immunohistochemical methods the effects of the deletion of the Otx1 gene on 12 areas of the cerebral cortex and on neurons expressing Ca-binding proteins (CaBP), such as parvalbumin (Pv) and calbindin-D28K (Cb). We found that the deletion of the Otx1 gene modified differently the various cortical areas. The decrease in cortical thickness ranged from 29.35 to 9.85% and the reduction in cellular population from 35.90 to 3.65% in the different cortical areas. The influence of the Otx1 gene concerns all cortical layers with variable effects on different cortical areas. The cellular population of cerebral cortex considered as a whole was reduced by 20.67%, Pv-positive (Pv+) cells by 58.01% and Cb-positive (Cb+) cells by 51.54%. The quantitative distribution of Pv+ and Cb+ cells varied independently in the different cortical areas. Topographic analysis of CaBP cells in Otx1-null mice (Otx1(-/-)) showed that Pv+ cells were principally distributed in layers IV and V and Cb+ cells in layers V and VI. Given that in the development of wild-type mice both cell types first appear in deep layers and later spread to superficial ones, the segregation of CaBP neurons in inner layers of Otx1(-/-) animals is an index of the immaturity of the cerebral cortex of these animals. This study showed that the Otx1 gene has a more complex role than previously reported, as it is involved in the maturation and differentiation of various cerebral cortices, and, specifically, in the development of CaBP cells.
authors.affiliation: Department of Physiological Science, University of Catania, Viale A. Doria, 6, 95125-Catania, Italy.
authors.forename: Maria Rosita
authors.initials: MR
authors.lastname: Pantò
authors.forename: Agata
authors.initials: A
authors.lastname: Zappalà
authors.forename: Francesca
authors.initials: F
authors.lastname: Tuorto
authors.forename: Federico
authors.initials: F
authors.lastname: Cicirata
mesh_terms: D000818:Animals; D064092:Calbindin 1; D064026:Calbindins; D002135:Calcium-Binding Proteins / Q000378:metabolism; D002452:Cell Count / Q000379:methods; D002454:Cell Differentiation / Q000235:genetics*; D002540:Cerebral Cortex / Q000166:cytology* / Q000378:metabolism; D003952:Diagnostic Imaging / Q000379:methods; D018398:Homeodomain Proteins / Q000235:genetics / Q000502:physiology*; D007150:Immunohistochemistry / Q000379:methods; D051379:Mice; D008822:Mice, Transgenic; D009474:Neurons / Q000166:cytology* / Q000378:metabolism; D051857:Otx Transcription Factors; D010320:Parvalbumins / Q000378:metabolism; D064030:S100 Calcium Binding Protein G / Q000378:metabolism; D019749:Sulfur-Sulfur Bond Isomerases / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*
chemical_list: C576499:Calb1 protein, mouse; D064092:Calbindin 1; D064026:Calbindins; D002135:Calcium-Binding Proteins; D018398:Homeodomain Proteins; D051857:Otx Transcription Factors; C497656:Otx1 protein, mouse; D010320:Parvalbumins; D064030:S100 Calcium Binding Protein G; D014157:Transcription Factors; C085577:Ca2+-binding protein-1; D019749:Sulfur-Sulfur Bond Isomerases