Expression of Floor Plate in Dispersed Mesencephalic Cultures: Role in Differentiation of Tyrosine Hydroxylase Neurons

• Published in: Experimental neurology 1997-10, Vol.147 (2), p.525-531
• Main Authors: Cohen, Benjamin R., Sladek, Celia D.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Biomarkers; Cell Communication; Cell Differentiation; Cell Division; Cells, Cultured; Development. Senescence. Regeneration. Transplantation; DNA-Binding Proteins - biosynthesis; DNA-Binding Proteins - genetics; Dopamine - biosynthesis; Embryonic and Fetal Development; Embryonic Induction - physiology; Enzyme Induction; Fundamental and applied biological sciences. Psychology; Hepatocyte Nuclear Factor 3-beta; Mesencephalon - cytology; Mesencephalon - embryology; Mesencephalon - enzymology; Nerve Tissue Proteins - analysis; Nerve Tissue Proteins - biosynthesis; Nerve Tissue Proteins - genetics; Neurons - enzymology; Neurons - physiology; Nuclear Proteins - biosynthesis; Nuclear Proteins - genetics; Rats; Rats, Sprague-Dawley; Transcription Factors; Tyrosine 3-Monooxygenase - analysis; Vertebrates: nervous system and sense organs
• ISSN: 0014-4886; 1090-2430
• DOI: 10.1006/exnr.1997.6621

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-3β 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 proliferationin vitro.The number of TH cells increased 14× between 48 h and 1 week in culture. In dispersed E-14 cultures, the presence of FP4 and HNF-3β 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-3β mRNA added daily to cultured E-14 cells blocked the HNF-3β 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.