Expression of gp100 and CDK2 in melanoma cells is not co-regulated by a shared promoter region

Lawrence S. Stennett, Adam I. Riker, Tara M. Kroll, Janine Chamberlin, Toru Miki, Brian J. Nickoloff, I. Caroline Le Poole*

*Corresponding author for this work

Research output: Contribution to journalArticle

8 Scopus citations

Abstract

Expression of the pigmentation-associated gene PMel17 is regulated by a 1 kB promoter region shared between the PMel17 and CDK2 genes. The encoded melanosomal glycoprotein gp100 and the cell cycle regulatory protein CDK2 are transcribed in opposite directions. Luciferase reporter constructs were generated for subregions of the promoter containing 0, 1, 2 or 3 putative binding sites for transcription factors with basic helix-loop-helix (bHLH) motifs. The potential contribution of bHLH transcription factor microphthalmia transcription factor (MITF) to promoter activity was investigated by re-introducing microphthalmia into melanoma cells lacking expression. A bi-directional reporter construct was generated to investigate potential co-regulation of gp100 and CDK2 transcription. Promoter activity was assessed in presence and absence of phorbol ester tetradecanoyl phorbol 13-acetate (TPA). FACS analysis and immunohistology served to evaluate co-regulation of gp100 and CDK2 expression at the protein level. The full-length promoter, including a consensus binding site for MITF was found to contain sequences that suppressed gp100 expression. Introduction of MITF into nonexpressing 1123 melanoma cells did not restore gp100 expression levels. A lack of coregulation for gp100 and CDK2 as suggested by immunostaining was supported by findings of dissimilar expression regulation by TPA for either gene. The current study provides insight into transcriptional regulation of the PMel17 and CDK2 genes, important to identify strategies for modulating expression of gp100 and CDK2 proteins by melanoma cells.

Original languageEnglish (US)
Pages (from-to)525-532
Number of pages8
JournalPigment Cell Research
Volume17
Issue number5
DOIs
StatePublished - Oct 1 2004

Keywords

  • Cyclin dependent kinase 2
  • Gene expression
  • gp100
  • Melanoma
  • Promoter
  • Transcription factor
  • Tumor associated antigen

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Plant Science
  • Developmental Biology
  • Clinical Biochemistry
  • Cell Biology

Fingerprint Dive into the research topics of 'Expression of gp100 and CDK2 in melanoma cells is not co-regulated by a shared promoter region'. Together they form a unique fingerprint.

  • Cite this