Regulation of human tyrosine hydroxylase gene by neuron-restrictive silencer factor.
Tyrosine hydroxylase (TH), the biosynthetic enzyme of catecholamine, is synthesized specifically in catecholaminergic neurons. Thus, it is possible that neuronal cell type-specific expression of this gene is coordinately regulated. One of the neuron-specific transcription regulators, neuron-restrictive silencer factor (NRSF)/repressor element 1 (RE1) silencing transcription factor (REST), represses the expression of neuronal genes in non-neuronal cells. To elucidate the molecular mechanisms that control catecholaminergic neuronal expression of human TH, we initially characterized the 5' regulatory region. Previous studies have shown that a 3174 bp fragment of the human TH promoter confers specific expression to the reporter gene in dopaminergic neuron-like cell lines. Within this 5' regulatory region, three putative neuron-restrictive silencer elements (NRSE)/RE1 were identified, which bound NRSF/REST in a sequence-specific manner, as confirmed using EMSA and ChIP assays. In transient transfection assays, deletion or mutation of NRSE/RE1 elements led to a 7-fold increase in activity of the 3.2 kb TH promoter in human neural stem cells (NSCs), but had no major effects on differentiated neuron-like cells. Suppression of NRSF/REST functions with either the histone deacetylase inhibitor, trichostatin, or DN-NRSF induced TH promoter activity. Our data strongly suggest that NRSF/REST functions as a repressor of TH transcription in NSCs via a mechanism dependent on the TH NRSE/RE1 sites.
Kim
Soo Min
SM
Neuroscience Graduate Program, Ajou University School of Medicine, Suwon, Republic of Korea.
Yang
Jae Won
JW
Park
Mi Jung
MJ
Lee
Joon-Kyu
JK
Kim
Seung U
SU
Lee
Young Seek
YS
Lee
Myung Ae
MA
D001483:Base Sequence; D002454:Cell Differentiation; D002460:Cell Line; D004789:Enzyme Activation; D005786:Gene Expression Regulation; D056572:Histone Deacetylase Inhibitors; D006801:Humans; D009154:Mutation; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D050436:Regulatory Elements, Transcriptional; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D015533:Transcriptional Activation; D014446:Tyrosine 3-Monooxygenase / Q000096:biosynthesis* / Q000235:genetics; D000099229:RE1-Silencing Transcription Factor
D056572:Histone Deacetylase Inhibitors; D012097:Repressor Proteins; D014157:Transcription Factors; D014446:Tyrosine 3-Monooxygenase; D000099229:RE1-Silencing Transcription Factor