Expression of the gene encoding tyrosine hydroxylase in a subpopulation of quail dorsal root ganglion cells cultured in the presence of insulin or chick embryo extract.
Avian sensory ganglia contain a population of normally latent autonomic precursors with catecholaminergic potentialities. The present study examines the expression of the tyrosine hydroxylase (TH) gene in quail dorsal root ganglia (DRG) by both in situ hybridization and polymerase chain reaction (PCR) techniques. In situ hybridization using quail TH cDNA as a probe demonstrated the presence in DRG cell cultures of TH mRNA in a subpopulation of cells that never express the adrenergic phenotype in vivo. Expression of the TH gene in autonomic precursor cells of DRG in culture is totally dependent on the presence either of insulin or chick embryo extract. The numbers of catecholaminergic cells expressing TH mRNA and TH immunoreactivity evolve in a closely similar manner during the culture period. Using two primers, specific for highly conserved 5' regions of TH cDNA, it was possible to detect the same band of DNA amplified by PCR in total RNA from DRG cultures grown in the presence of insulin, sympathetic ganglia and adrenal gland. No amplified DNA was detected in uncultured DRG cells. These data further indicate that, under the influence either of insulin or a still unknown factor contained in the CEE, the TH gene is induced in a subpopulation of DRG cells.
Institut d'Embryologie Cellulaire et Moléculaire du CNRS, Nogent-sur-Marne, France.
Z G
ZG
Xue
X J
XJ
Xue
M
M
Fauquet
J
J
Smith
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N
Le Douarin
D000818:Animals; D001483:Base Sequence; D002642:Chick Embryo; D003370:Coturnix / Q000235:genetics* / Q000378:metabolism; D005727:Ganglia, Spinal / Q000166:cytology / Q000201:enzymology* / Q000254:growth & development; D005784:Gene Amplification; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007328:Insulin / Q000494:pharmacology*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis / Q000302:isolation & purification; D014446:Tyrosine 3-Monooxygenase / Q000096:biosynthesis* / Q000235:genetics
D007328:Insulin; D012333:RNA, Messenger; D014446:Tyrosine 3-Monooxygenase