Nucleic Acids Research, 1992, Vol. 20, No. 1 117-123
© 1992
MOLECULAR BIOLOGY |
Human Calcitonin gene regulation by helix-loop-nelix recognition sequences
1Department of Medicine, The Johns Hopkins University School of Medicine 424 N. Bond Street, Baltimore, MD 21231, USA 2The Oncology Center, The Johns Hopkins University School of Medicine 424 N. Bond Street, Baltimore, MD 21231, USA
Received August 20, 1991. Revised November 26, 1991. Accepted November 26, 1991.
Human calcitonin (CT) gene transcription is regulated by proximal 5' flanking sequences which mediate cAMP-induced expression, and by a distal basal enhancer region. Using transient expression of CT-CAT constructs, we showed that the basalt enhancer is active in a CT-producing small cell lung cancer cell line (DMS53) and the thyroid C cell derived tumor line, TT, but is inactive in non-CT-producing cell lines. In deletional and direct mutational analyses of the distal enhancer region, disruption of two elements resembling recognition sequences for the helix-loop-helix (HLH) family of transcriptional regulatory proteins resulted in a significant loss of basal transcriptional enhancer action. These results suggest that HLH recognition motifs may mediate a significant portion of constitutive CT gene transcriptional activity in these cells. Nuclear protein extracts from DMS53 cells formed specific binding complexes with oligonucleotides containing two of these candidate enhancer sequences. However, proteins capable of binding to these CT gene HLH consensus recognition sites were not restricted to CT-producing cells. We conclude that members of the HLH protein family, some expressed ubiquitously and some expressed or activated in a tissue-restricted fashion, may combine to enhance CT gene transcription in tumor cells of neuroendocrine derivation.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
T. J. Viney, T. W. Schmidt, W. Gierasch, A. W. Sattar, R. E. Yaggie, A. Kuburas, J. P. Quinn, J. M. Coulson, and A. F. Russo Regulation of the Cell-specific Calcitonin/Calcitonin Gene-related Peptide Enhancer by USF and the Foxa2 Forkhead Protein J. Biol. Chem., November 26, 2004; 279(48): 49948 - 49955. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. L. Durham and A. F. Russo Stimulation of the Calcitonin Gene-Related Peptide Enhancer by Mitogen-Activated Protein Kinases and Repression by an Antimigraine Drug in Trigeminal Ganglia Neurons J. Neurosci., February 1, 2003; 23(3): 807 - 815. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. M. Lanigan and A. F. Russo Binding of Upstream Stimulatory Factor and a Cell-specific Activator to the Calcitonin/Calcitonin Gene-related Peptide Enhancer J. Biol. Chem., July 18, 1997; 272(29): 18316 - 18324. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Morel, M. Cordier-Bussat, and J. Philippe The Upstream Promoter Element of the Glucagon Gene, G1, Confers Pancreatic Alpha Cell-specific Expression J. Biol. Chem., February 17, 1995; 270(7): 3046 - 3055. [Abstract] [Full Text] [PDF] |
||||

