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.
Copyright (c) 2009 Elsevier B.V. All rights reserved.