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Updated: May 29, 2026

Analysis of the c-KIT Ligand Promoter Using Chromatin Immunoprecipitation
09:40

Analysis of the c-KIT Ligand Promoter Using Chromatin Immunoprecipitation

Published on: June 27, 2017

C-KIT signaling depends on microphthalmia-associated transcription factor for effects on cell proliferation

Bengt Phung1, Jianmin Sun, Alexander Schepsky

  • 1Wallenberg Laboratory, Experimental Clinical Chemistry, Department of Laboratory Medicine, Lund University, Skåne University Hospital, Malmö, Sweden. bengt.phung@med.lu.se

Plos One
|September 3, 2011
PubMed

Insights

The tyrosine kinase receptor c-KIT regulates melanocyte development and melanoma by activating the transcription factor Mitf. This study identifies key c-KIT phosphorylation sites and signaling pathways essential for Mitf activation and cell proliferation.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cancer Research

Background:

  • Melanocyte development relies on the tyrosine kinase receptor c-KIT and transcription factor Mitf.
  • Both c-KIT and Mitf are crucial for melanocyte survival and are implicated in malignant melanoma.
  • Mechanisms regulating c-KIT signaling and Mitf activation remain incompletely understood.

Purpose of the Study:

  • To elucidate the signaling pathways and mechanisms underlying c-KIT-mediated regulation of Mitf.
  • To identify specific c-KIT phosphorylation sites critical for Mitf activation.
  • To investigate the role of Mitf in c-KIT-driven cell proliferation.

Main Methods:

  • Stimulation of c-KIT and analysis of Mitf activation.
  • Site-directed mutagenesis of c-KIT phosphorylation sites (Y721, Y568, Y570).
  • Pharmacological inhibition of key kinases (PI3K, Akt, Src, p38, Mek) and assessment of Mitf activation and cell proliferation.

Main Results:

  • c-KIT activation of Mitf is dependent on phosphorylation at Y721 (PI3K binding), Y568, and Y570 (Src binding sites).
  • The Ras-Erk pathway is involved, and Src kinase binding to c-KIT is required for Mitf activation.
  • c-KIT-induced cell proliferation in HEK293T cells is Mitf-dependent and impaired in Y568F and Y721F mutants.

Conclusions:

  • Novel mechanisms reveal c-KIT signaling regulates Mitf through specific phosphorylation sites and downstream kinases.
  • Src kinase and PI3K/Akt/MAPK pathways are critical for c-KIT-mediated Mitf activation.
  • Understanding these pathways offers insights into melanocyte development and melanoma pathogenesis.

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