KSHV-encoded miRNAs target MAF to induce endothelial cell reprogramming

Genes Dev. 2010 Jan 15;24(2):195-205. doi: 10.1101/gad.553410.

Abstract

Kaposi sarcoma herpesvirus (KSHV) induces transcriptional reprogramming of endothelial cells. In particular, KSHV-infected lymphatic endothelial cells (LECs) show an up-regulation of genes associated with blood vessel endothelial cells (BECs). Consequently, KSHV-infected tumor cells in Kaposi sarcoma are poorly differentiated endothelial cells, expressing markers of both LECs and BECs. MicroRNAs (miRNAs) are short noncoding RNA molecules that act post-transcriptionally to negatively regulate gene expression. Here we validate expression of the KSHV-encoded miRNAs in Kaposi sarcoma lesions and demonstrate that these miRNAs contribute to viral-induced reprogramming by silencing the cellular transcription factor MAF (musculoaponeurotic fibrosarcoma oncogene homolog). MAF is expressed in LECs but not in BECs. We identify a novel role for MAF as a transcriptional repressor, preventing expression of BEC-specific genes, thereby maintaining the differentiation status of LECs. These findings demonstrate that viral miRNAs could influence the differentiation status of infected cells, and thereby contribute to KSHV-induced oncogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Differentiation
  • Cell Line
  • Cell Line, Tumor
  • Cellular Reprogramming*
  • Down-Regulation
  • Endothelial Cells / cytology*
  • Endothelial Cells / metabolism
  • Endothelial Cells / pathology*
  • Endothelial Cells / virology
  • Gene Expression Regulation, Viral
  • Gene Silencing
  • HeLa Cells
  • Herpesviridae Infections / physiopathology
  • Herpesvirus 8, Human / genetics
  • Herpesvirus 8, Human / metabolism*
  • Humans
  • MicroRNAs / metabolism*
  • Oncogene Protein v-maf / metabolism*
  • Sarcoma, Kaposi / physiopathology*

Substances

  • MicroRNAs
  • Oncogene Protein v-maf