title: Comparative analysis of monoaminergic cerebrospinal fluid-contacting cells in Osteichthyes (bony vertebrates).
abstract: Cerebrospinal fluid-contacting (CSF-c) cells containing monoamines such as dopamine (DA) and serotonin (5-HT) occur in the periventricular zones of the hypothalamic region of most vertebrates except for placental mammals. Here we compare the organization of the CSF-c cells in chicken, Xenopus, and zebrafish, by analyzing the expression of synthetic enzymes of DA and 5-HT, respectively, tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH), and draw an evolutionary scenario for this cell population. Due to the lack of TH immunoreactivity in this region, the hypothalamic CSF-c cells have been thought to take up DA from the ventricle instead of synthesizing it. We demonstrate that a second TH gene (TH2) is expressed in the CSF-c cells of all the three species, suggesting that these cells do indeed synthetize DA. Furthermore, we found that many CSF-c cells coexpress TH2 and TPH1 and contain both DA and 5-HT, a dual neurotransmitter phenotype hitherto undescribed in the brain of any vertebrate. The similarities of CSF-c cells in chicken, Xenopus, and zebrafish suggest that these characteristics are inherited from the common ancestor of the Osteichthyes. A significant difference between tetrapods and teleosts is that teleosts possess an additional CSF-c cell population around the posterior recess (PR) that has emerged in specific groups of Actinopterygii. Our comparative analysis reveals that the hypothalamus in mammals and teleosts has evolved in a divergent manner: placental mammals have lost the monoaminergic CSF-c cells, while teleosts have increased their relative number.
authors.affiliation: Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Anna L
authors.initials: AL
authors.lastname: Xavier
authors.affiliation: Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Romain
authors.initials: R
authors.lastname: Fontaine
authors.affiliation: Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Solal
authors.initials: S
authors.lastname: Bloch
authors.affiliation: TEFOR Core Facility, Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Affaticati
authors.affiliation: TEFOR Core Facility, Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Arnim
authors.initials: A
authors.lastname: Jenett
authors.affiliation: Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Michaël
authors.initials: M
authors.lastname: Demarque
authors.affiliation: Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Vernier
authors.affiliation: Paris-Saclay Institute of Neuroscience (Neuro-PSI), CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France.
authors.forename: Kei
authors.identifier: http://orcid.org/0000-0002-8775-9022
authors.initials: K
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism*; D005075:Biological Evolution; D001921:Brain / Q000166:cytology* / Q000378:metabolism; D002555:Cerebrospinal Fluid / Q000502:physiology*; D002642:Chick Embryo; D002645:Chickens; D051959:ELAV Proteins / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D021621:Imaging, Three-Dimensional; D008297:Male; D009474:Neurons / Q000145:classification / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D014714:Vertebrates; D014981:Xenopus; D015027:Zebrafish; D062826:Zonula Occludens-1 Protein / Q000378:metabolism
chemical_list: D015306:Biogenic Monoamines; D051959:ELAV Proteins; D012333:RNA, Messenger; C569042:TJP1 protein, human; D062826:Zonula Occludens-1 Protein; D049452:Green Fluorescent Proteins
keywords: CSF-contacting cells; RRID: AB_10000240; RRID: AB_2201528; RRID: AB_221448; RRID: AB_2314334; RRID: AB_2314655; RRID: AB_477522; RRID: AB_87181; RRID: AB_94865; dopamine; evolution; hypothalamus; monoamine; paraventricular organ; serotonin; ventricle