title: From hindbrain segmentation to breathing after birth: developmental patterning in rhombomeres 3 and 4.
abstract: Respiration is a rhythmic motor behavior that appears in the fetus and acquires a vital importance at birth. It is generated within central pattern-generating neuronal networks of the hindbrain. This region of the brain is of particular interest since it is the most understood part with respect to the cellular and molecular mechanisms that underlie its development. Hox paralogs and Hox-regulating genes kreisler/mafB and Krox20 are required for the normal formation of rhombomeres in vertebrate embryos. From studies of rhombomeres r3 and r4, the authors review mechanisms whereby these developmental genes may govern the early embryonic development of para-facial neuronal networks and specify patterns of motor activities operating throughout life. A model whereby the regional identity of progenitor cells can be abnormally specified in r3 and r4 after a mutation of these genes is proposed. Novel neuronal circuits may develop from some of these misspecified progenitors while others are eliminated, eventually affecting respiration and survival after birth.
authors.affiliation: UPR 2216 Neurobiologie Génétique et Intégrative, Institut de Neurobiologie Alfred Fessard, CNRS, 1 avenue de la Terrasse, 91198 Gif-sur-Yvette, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Chatonnet
authors.forename: Eduardo
authors.initials: E
authors.lastname: Domínguez del Toro
authors.forename: Muriel
authors.initials: M
authors.lastname: Thoby-Brisson
authors.forename: Jean
authors.initials: J
authors.lastname: Champagnat
authors.forename: Gilles
authors.initials: G
authors.lastname: Fortin
authors.forename: Filippo M
authors.initials: FM
authors.lastname: Rijli
authors.forename: Christelle
authors.initials: C
authors.lastname: Thaëron-Antôno
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D005801:Genes, Homeobox / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D009421:Nervous System Malformations / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D012125:Respiratory Center / Q000166:cytology / Q000196:embryology* / Q000502:physiology*; D012127:Respiratory Distress Syndrome, Newborn / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D012249:Rhombencephalon / Q000166:cytology / Q000196:embryology* / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism