GAP junctional communication in brain secondary organizers.
Gap junctions (GJs) are integral membrane proteins that enable the direct cytoplasmic exchange of ions and low molecular weight metabolites between adjacent cells. They are formed by the apposition of two connexons belonging to adjacent cells. Each connexon is formed by six proteins, named connexins (Cxs). Current evidence suggests that gap junctions play an important part in ensuring normal embryo development. Mutations in connexin genes have been linked to a variety of human diseases, although the precise role and the cell biological mechanisms of their action remain almost unknown. Among the big family of Cxs, several are expressed in nervous tissue but just a few are expressed in the anterior neural tube of vertebrates. Many efforts have been made to elucidate the molecular bases of Cxs cell biology and how they influence the morphogenetic signal activity produced by brain signaling centers. These centers, orchestrated by transcription factors and morphogenes determine the axial patterning of the mammalian brain during its specification and regionalization. The present review revisits the findings of GJ composed by Cx43 and Cx36 in neural tube patterning and discuss Cx43 putative enrollment in the control of Fgf8 signal activity coming from the well known secondary organizer, the isthmic organizer.
Instituto de Neurociencias, Universidad Miguel Hernández & Consejo Superior de Investigaciones Científicas, 03550, Sant Joan d'Alacant, Spain.
Camilla
C
Bosone
Institut de Biologie Paris-Seine (IBPS), Developmental Biology Laboratory, University Pierre and Marie Curie, Paris, France.
Abraham
A
Andreu
Instituto de Neurociencias, Universidad Miguel Hernández & Consejo Superior de Investigaciones Científicas, 03550, Sant Joan d'Alacant, Spain.
Diego
D
Echevarria
D000818:Animals; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism*; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D051524:Fibroblast Growth Factor 8 / Q000235:genetics / Q000378:metabolism*; D017629:Gap Junctions / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009154:Mutation; D054259:Neural Tube / Q000196:embryology*; D038081:Organogenesis / Q000502:physiology*; D000097004:Gap Junction delta-2 Protein
D018031:Connexin 43; D017630:Connexins; D051524:Fibroblast Growth Factor 8; D000097004:Gap Junction delta-2 Protein; C496456:FGF8 protein, human
Cx36; Cx43; Fgf8; gap junction; isthmic organizer; mammalian neural tube patterning; morphogenesis