title: Breathing with phox2b.
abstract: In the last few years, elucidation of the architecture of breathing control centres has reached the cellular level. This has been facilitated by increasing knowledge of the molecular signatures of various classes of hindbrain neurons. Here, we review the advances achieved by studying the homeodomain factor Phox2b, a transcriptional determinant of neuronal identity in the central and peripheral nervous systems. Evidence from human genetics, neurophysiology and mouse reverse genetics converges to implicate a small population of Phox2b-dependent neurons, located in the retrotrapezoid nucleus, in the detection of CO(2), which is a paramount source of the 'drive to breathe'. Moreover, the same and other studies suggest that an overlapping or identical neuronal population, the parafacial respiratory group, might contribute to the respiratory rhythm at least in some circumstances, such as for the initiation of breathing following birth. Together with the previously established Phox2b dependency of other respiratory neurons (which we review briefly here), our new data highlight a key role of this transcription factor in setting up the circuits for breathing automaticity.
authors: Ecole normale supérieure, Département de Biologie, 75005 Paris, France.
authors: Véronique
authors: V
authors: Dubreuil
authors: Jacques
authors: J
authors: Barhanin
authors: Christo
authors: C
authors: Goridis
authors: Jean-François
authors: JF
authors: Brunet
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007040:Hypoventilation / Q000378:metabolism*; D051379:Mice; D009154:Mutation / Q000235:genetics; D009474:Neurons / Q000378:metabolism*; D015656:Respiratory Mechanics / Q000502:physiology*; D012249:Rhombencephalon / Q000166:cytology / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D018398:Homeodomain Proteins; C109220:NBPhox protein; D014157:Transcription Factors; D002245:Carbon Dioxide