MITF and TFEB cross-regulation in melanoma cells

PLoS One. 2020 Sep 3;15(9):e0238546. doi: 10.1371/journal.pone.0238546. eCollection 2020.

Abstract

The MITF, TFEB, TFE3 and TFEC (MiT-TFE) proteins belong to the basic helix-loop-helix family of leucine zipper transcription factors. MITF is crucial for melanocyte development and differentiation, and has been termed a lineage-specific oncogene in melanoma. The three related proteins MITF, TFEB and TFE3 have been shown to be involved in the biogenesis and function of lysosomes and autophagosomes, regulating cellular clearance pathways. Here we investigated the cross-regulatory relationship of MITF and TFEB in melanoma cells. Like MITF, the TFEB and TFE3 genes are expressed in melanoma cells as well as in melanoma tumors, albeit at lower levels. We show that the MITF and TFEB proteins, but not TFE3, directly affect each other's mRNA and protein expression. In addition, the subcellular localization of MITF and TFEB is subject to regulation by the mTOR signaling pathway, which impacts their cross-regulatory relationship at the transcriptional level. Our work shows that the relationship between MITF and TFEB is multifaceted and that the cross-regulatory interactions of these factors need to be taken into account when considering pathways regulated by these proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / physiology*
  • Cell Line, Tumor
  • HEK293 Cells
  • Humans
  • Melanoma / metabolism*
  • Microphthalmia-Associated Transcription Factor / physiology*
  • Signal Transduction
  • TOR Serine-Threonine Kinases / physiology

Substances

  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • MITF protein, human
  • Microphthalmia-Associated Transcription Factor
  • TFE3 protein, human
  • TFEB protein, human
  • MTOR protein, human
  • TOR Serine-Threonine Kinases

Associated data

  • figshare/10.6084/m9.figshare.12568646

Grants and funding

ES, 130230-052, Research fund of Iceland, www.rannis.is ES, 163413-051, Research fund of Iceland, www.rannis.is.