ZFIN ID: ZDB-PUB-061108-3
Differential regulation of the zebrafish orthopedia1 gene during fate determination of diencephalic neurons
Del Giacco, L., Sordino, P., Pistocchi, A., Andreakis, N., Tarallo, R., Di Benedetto, B., and Cotelli, F.
Date: 2006
Source: BMC Developmental Biology   6: 50 (Journal)
Registered Authors: Cotelli, Franco, Del Giacco, Luca, Sordino, Paolo
Keywords: none
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Diencephalon/growth & development*
  • Diencephalon/metabolism*
  • Gene Expression Regulation, Developmental/genetics
  • Gene Expression Regulation, Developmental/physiology*
  • Homeodomain Proteins/biosynthesis
  • Homeodomain Proteins/genetics
  • Molecular Sequence Data
  • Nerve Tissue Proteins/biosynthesis
  • Nerve Tissue Proteins/genetics
  • Neurons/cytology
  • Neurons/metabolism*
  • Neurons/physiology
  • Phylogeny
  • Protein Isoforms/biosynthesis
  • Protein Isoforms/genetics
  • Transcription Factors/biosynthesis*
  • Transcription Factors/genetics
  • Zebrafish/embryology
  • Zebrafish/genetics
  • Zebrafish/growth & development*
  • Zebrafish Proteins/biosynthesis*
  • Zebrafish Proteins/genetics
PubMed: 17074092 Full text @ BMC Dev. Biol.
ABSTRACT: BACKGROUND: The homeodomain transcription factor Orthopedia (Otp) is essential in restricting the fate of multiple classes of secreting neurons in the neuroendocrine hypothalamus of vertebrates. However, there is little information on the intercellular factors that regulate Otp expression during development. RESULTS: Here, we identified two otp orthologues in zebrafish (otp1 and otp2) and explored otp1 in the context of the morphogenetic pathways that specify neuroectodermal regions. During forebrain development, otp1 is expressed in anterior groups of diencephalic cells, positioned in the preoptic area (PO) (anterior alar plate) and the posterior tuberculum (PT) (posterior basal plate). The latter structure is characterized by Tyrosine Hydroxylase (TH)-positive cells, suggesting a role for otp1 in the lineage restriction of catecholaminergic (CA) neurons. Disruptions of Hedgehog (HH) and Fibroblast Growth Factor (FGF) pathways point to the ability of SHH protein to trigger otp1 expression in PO presumptive neuroblasts, with the attenuating effect of Dzip1 and FGF8. In addition, our data disclose otp1 as a determinant of CA neurons in the PT, where otp1 activity is strictly dependent on Nodal signaling and it is not responsive to SHH and FGF. CONCLUSIONS: In this study, we pinpoint the evolutionary importance of otp1 transcription factor in cell states of the diencephalon anlage and early neuronal progenitors. Furthermore, our data indicate that morphogenetic mechanisms differentially regulate otp1 expression in alar and basal plates.