TY - JOUR
T1 - Transcriptional regulation of human MAP2 gene in melanoma
T2 - Role of neuronal bHLH factors and Notch1 signaling
AU - Bhat, Kumar M.R.
AU - Maddodi, Nityanand
AU - Shashikant, Cooduvalli
AU - Setaluri, Vijayasaradhi
N1 - Funding Information:
We thank Dr Kageyama for providing pCI-Hes1 construct and anti-Hes1 antibody, Dr Jan for providing pcDNA-NeuroD1-FLAG construct, and Dr Suh-Kim for providing NeuroD antibody. We also thank Ms. Smita Ramprakash, Ms. Namratha Sangha and Dr Pichardo for valuable technical help, and Drs Rajendra Kedlaya and Akihiro Ikeda for comments and suggestions. Funding to pay the Open Access publication charges for this article was provided by the Department of Dermatology, University of Wisconsin, Madison, USA.
PY - 2006
Y1 - 2006
N2 - Microtubule-associated protein 2 (MAP2), a neuron-specific protein, stabilizes microtubules and is critical for neurite outgrowth and dendrite development. Although MAP2 is widely used as a marker of neuronal differentiation, regulation of its transcription has not been investigated. We showed that MAP2 is frequently activated in human cutaneous melanoma. Here, we identified a 2.2 kb region that is sufficient for neuronal-specific expression in vitro and in vivo. Comparative analysis of the mouse, rat and human MAP2 promoter sequences showed the presence of a conserved bHLH factor binding sites. Electrophoretic mobility shift analysis, promoter mutagenesis and co-transfection experiments showed that NeuroD, a pro-neuronal differentiation factor, and Hairy and Enhancer of Split (HES1), a transcription repressor, are involved in the regulation of MAP2 promoter activity. Melanoma cells express both NeuroD and HES1. Chromatin immunoprecipitation showed that in metastatic melanoma cells N-box region of the MAP2 promoter is occupied by endogenous HES1. We show that the inhibition of Notch signaling, a regulator of HES1 gene expression, and/or shRNA knockdown of HES1 results in the upregulation of MAP2 promoter activity. Thus, our data suggest that Notch signaling, which is implicated in melanoma progression, and HES1 play a role in MAP2 gene regulation during melanoma progression.
AB - Microtubule-associated protein 2 (MAP2), a neuron-specific protein, stabilizes microtubules and is critical for neurite outgrowth and dendrite development. Although MAP2 is widely used as a marker of neuronal differentiation, regulation of its transcription has not been investigated. We showed that MAP2 is frequently activated in human cutaneous melanoma. Here, we identified a 2.2 kb region that is sufficient for neuronal-specific expression in vitro and in vivo. Comparative analysis of the mouse, rat and human MAP2 promoter sequences showed the presence of a conserved bHLH factor binding sites. Electrophoretic mobility shift analysis, promoter mutagenesis and co-transfection experiments showed that NeuroD, a pro-neuronal differentiation factor, and Hairy and Enhancer of Split (HES1), a transcription repressor, are involved in the regulation of MAP2 promoter activity. Melanoma cells express both NeuroD and HES1. Chromatin immunoprecipitation showed that in metastatic melanoma cells N-box region of the MAP2 promoter is occupied by endogenous HES1. We show that the inhibition of Notch signaling, a regulator of HES1 gene expression, and/or shRNA knockdown of HES1 results in the upregulation of MAP2 promoter activity. Thus, our data suggest that Notch signaling, which is implicated in melanoma progression, and HES1 play a role in MAP2 gene regulation during melanoma progression.
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U2 - 10.1093/nar/gkl476
DO - 10.1093/nar/gkl476
M3 - Article
C2 - 16916793
AN - SCOPUS:33747866678
SN - 0305-1048
VL - 34
SP - 3819
EP - 3832
JO - Nucleic acids research
JF - Nucleic acids research
IS - 13
ER -