Structure and Promoter Analysis of the Gene Encoding the Mouse Helix-Loop-Helix Factor HES-5
IDENTIFICATION OF THE NEURAL PRECURSOR CELL-SPECIFIC PROMOTER ELEMENT (*)
-
↵§ Present address: The Salk Institute for Biological Studies, La Jolla, CA 92037.
- ¶ To whom correspondence should be addressed: Institute for Immunology, Kyoto University Faculty of Medicine, Yoshida, Sakyo-ku, Kyoto 606, Japan. Tel.: 81-75-753-4438; Fax: 81-75-753-4404.
Abstract
HES-5 is a mammalian basic helix-loop-helix factor that has a distant sequence homology to the product of the Drosophila pair-rule gene hairy. HES-5 mRNA is present exclusively in the developing nervous system, but its level decreases as neural differentiation proceeds. In this study, to characterize the molecular mechanism of the neural-specific expression of HES-5 we isolated the mouse HES-5 gene. This gene consists of three exons, and Southern blot analysis shows that it is a single copy gene. The transcription initiation site, determined by primer extension and reverse transcriptase-mediated polymerase chain reaction, is located 26 nucleotides downstream of a TATA box. Transient transfection analysis shows that the upstream region of the HES-5 gene can direct efficient expression in neural precursor cells and moderate expression in undifferentiated NCB20 neuroblastoma-brain hybrid cells but not in glioma or fibroblast cells. The moderate level of expression in NCB20 cells decreases when differentiation into neuron-like cells is induced. Further promoter analysis shows that this undifferentiated neural-specific expression is mediated by the multiple GC stretches present in the HES-5 promoter. Gel mobility shift analysis suggests the presence of a neural precursor cell-specific protein that binds to the GC stretches. These results raise the possibility that HES-5 expression in the developing nervous system is regulated by the GC stretch-binding protein.
Footnotes
-
↵* This work was supported by research grants from the Ministry of Education, Science, and Culture of Japan, the Sankyo Foundation, and the Inamori Foundation. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore by hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
The nucleotide sequence(s) reported in this paper has been submitted to the GenBank(TM)/EMBL Data Bank with accession number(s) D32132[GenBank].
-
↵1 The abbreviations used are:
- CNS
-
central nervous system
- HLH
-
helix-loop-helix
- bHLH
-
basic HLH
- kb
-
kilobases
- bp
-
base pairs
- E
-
embryonic day
- RT-PCR
-
reverse transcriptase-mediated polymerase chain reaction.
-
- Received October 17, 1994.
- © 1995 by The American Society for Biochemistry and Molecular Biology, Inc.
