Dicer knockdown induces fibronectin-1 expression in HEK293T cells via induction of Egr1

Biochim Biophys Acta. 2010 Mar;1800(3):380-4. doi: 10.1016/j.bbagen.2009.11.009. Epub 2009 Nov 13.

Abstract

Background: Dicer is a multidomain ribonuclease III enzyme involved in the biogenesis of microRNAs (miRNAs) and small interfering RNAs (siRNAs); depletion of Dicer was found to impair the migration of endothelial cells.

Methods: siRNA transfection, cell migration assay, real-time RT-PCR, chromatin immunoprecipitation, Western blotting, ELISA, caspase-3 activity assay, and annexin-V-FITC assay were utilized.

Results: Knockdown of Dicer impairs the migratory capacity of HEK293T cells and induces fibronectin-1. The upregulation of fibronectin-1 is dependent on Egr1. Fibronectin-1/Dicer double-knockdown cells showed a marked increase in apoptosis compared with fibronectin-1 single knockdown cells.

Conclusions: Decreased Dicer expression induces fibronectin-1 expression via an Egr1-dependent manner.

General significance: Our data suggest that upregulation of fibronectin-1 protects Dicer knockdown HEK293T cells against apoptosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis
  • Blotting, Western
  • Cell Line
  • Cell Movement / physiology
  • Chromatin / genetics
  • DNA Primers
  • Early Growth Response Protein 1 / biosynthesis*
  • Enzyme-Linked Immunosorbent Assay
  • Fibronectins / genetics*
  • Fibronectins / physiology
  • Gene Expression
  • Gene Knockdown Techniques*
  • Humans
  • Kidney / embryology
  • Kidney / physiology*
  • RNA, Small Interfering / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Ribonuclease III / genetics*
  • Up-Regulation

Substances

  • Chromatin
  • DNA Primers
  • EGR1 protein, human
  • Early Growth Response Protein 1
  • Fibronectins
  • RNA, Small Interfering
  • Ribonuclease III