Expression of floor plate in dispersed mesencephalic cultures: role in differentiation of tyrosine hydroxylase neurons.
The availability of sufficient numbers of dopaminergic neurons for transplantation has been an important issue. Recently, it has been shown that the ventral floor plate (FP4-positive) cells and the transcription factor HNF-3beta are important in the signals that terminate proliferation and produce differentiation of the dopaminergic phenotype. In this study, dispersed mesencephalon from embryonic rats at Day 11 postcoitus (E-11), 1 day prior to the birth of TH cells, were cultured for 48 h and 1 week to evaluate TH neuronal differentiation and/or proliferation in vitro. The number of TH cells increased 14x between 48 h and 1 week in culture. In dispersed E-14 cultures, the presence of FP4 and HNF-3beta markers was demonstrated using immunohistochemistry. The majority of FP4-positive cell clusters were associated with TH neurons, suggesting that floor plate cells may have participated in TH neuron differentiation in culture. Antisense oligonucleotide probe for HNF-3beta mRNA added daily to cultured E-14 cells blocked the HNF-3beta expression, but had no effect on the FP4 or TH expression. These studies suggest a potentially important role for floor plate cells in the differentiation of TH cells, and differentiation and/or proliferation of TH cells in dispersed cultures of E-11 is demonstrated.
Cohen
B R
BR
Department of Physiology and Biophysics, Finch University of Health Sciences/The Chicago Medical School, North Chicago, Illinois 60064, USA.
Sladek
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CD
D000818:Animals; D015415:Biomarkers; D002450:Cell Communication; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D004298:Dopamine / Q000096:biosynthesis*; D004627:Embryonic Induction / Q000502:physiology*; D005314:Embryonic and Fetal Development; D004790:Enzyme Induction; D051542:Hepatocyte Nuclear Factor 3-beta; D008636:Mesencephalon / Q000166:cytology / Q000196:embryology* / Q000201:enzymology; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D009474:Neurons / Q000201:enzymology / Q000502:physiology*; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D014157:Transcription Factors; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis*
D015415:Biomarkers; D004268:DNA-Binding Proteins; C496504:Foxa2 protein, rat; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; D051542:Hepatocyte Nuclear Factor 3-beta; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine