RNA-induced silencing complex (RISC) Proteins PACT, TRBP, and Dicer are SRA binding nuclear receptor coregulators

Proc Natl Acad Sci U S A. 2013 Apr 16;110(16):6536-41. doi: 10.1073/pnas.1301620110. Epub 2013 Apr 2.

Abstract

The cytoplasmic RNA-induced silencing complex (RISC) contains dsRNA binding proteins, including protein kinase RNA activator (PACT), transactivation response RNA binding protein (TRBP), and Dicer, that process pre-microRNAs into mature microRNAs (miRNAs) that target specific mRNA species for regulation. There is increasing evidence for important functional interactions between the miRNA and nuclear receptor (NR) signaling networks, with recent data showing that estrogen, acting through the estrogen receptor, can modulate initial aspects of nuclear miRNA processing. Here, we show that the cytoplasmic RISC proteins PACT, TRBP, and Dicer are steroid receptor RNA activator (SRA) binding NR coregulators that target steroid-responsive promoters and regulate NR activity and downstream gene expression. Furthermore, each of the RISC proteins, together with Argonaute 2, associates with SRA and specific pre-microRNAs in both the nucleus and cytoplasm, providing evidence for links between NR-mediated transcription and some of the factors involved in miRNA processing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Carrier Proteins / metabolism*
  • Cell Fractionation
  • Chromatin Immunoprecipitation
  • Cloning, Molecular
  • DEAD-box RNA Helicases / metabolism*
  • Gene Expression Regulation / genetics*
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Luciferases
  • MCF-7 Cells
  • MicroRNAs / metabolism*
  • Plasmids / genetics
  • RNA Interference
  • RNA-Binding Proteins / metabolism*
  • RNA-Induced Silencing Complex / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Ribonuclease III / metabolism*
  • Transfection
  • Two-Hybrid System Techniques

Substances

  • Carrier Proteins
  • MicroRNAs
  • PRKRA protein, human
  • RNA-Binding Proteins
  • RNA-Induced Silencing Complex
  • steroid receptor RNA activator, human
  • trans-activation responsive RNA-binding protein
  • Luciferases
  • DICER1 protein, human
  • Ribonuclease III
  • DEAD-box RNA Helicases