[The regulatory mechanism for neuron specific expression of PACAP gene].
Pituitary adenylate cyclase-activating polypeptide (PACAP), a pleiotropic neuropeptide, is present abundantly in the central nervous system. In the 5'-flanking region of the PACAP gene, we found and characterized two negative regulatory elements, which are homologous to the neural-restrictive silencer element (NRSE). Their sequence and position were significantly conserved among mouse, human, and rat PACAP genes. NRSE is a crucial negative-acting DNA regulatory element for neuron-specific gene expression. NRSE acts through the transcription factor known as neural-restrictive silencer factor (NRSF). In non-neuronal cells, NRSF suppresses the expression of neuron-specific genes. On the other hand, in neuronal cells, NRnV, a NRSF truncated form, repress their expressions in a dominant negative manner. The electrophoretic mobility shift assay with 3T3 cells extract demonstrated the identical complexes among NRSLE-1, NRSLE2, and the NRSE of rat type II sodium channel gene. In the luciferase reporter assay, NRSLEs suppressed SV40 promoter activity in 3T3 cells, but not in PC12 cells. RT-PCR analysis revealed that PACAP and NRnV mRNAs are expressed in neuronal cells (differentiated PC12), but not in non-neuronal cells (3T3 or C6). These results suggested that the NRSE-NRSF system might be involved in the regulatory mechanism of neuron-specific expression of the PACAP gene.
Miyata
Atsuro
A
Department of Pharmacology, Postgraduate School of Medical and Dental Sciences, Kagoshima University, Japan. amiyata@m3.kufm.kagoshima-u.ac.jp
Sugawara
Hideki
H
Iwata
Shin-ichi
S
Shimizu
Takao
T
Kangawa
Kenji
K
D000818:Animals; D015870:Gene Expression / Q000235:genetics*; D006801:Humans; D051379:Mice; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051381:Rats; D037941:Silencer Elements, Transcriptional / Q000502:physiology*
C495401:ADCYAP1 protein, human; C495402:Adcyap1 protein, mouse; C495403:Adcyap1 protein, rat; D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide