KRAS Engages AGO2 to Enhance Cellular Transformation

Cell Rep. 2016 Feb 16;14(6):1448-1461. doi: 10.1016/j.celrep.2016.01.034. Epub 2016 Feb 4.

Abstract

Oncogenic mutations in RAS provide a compelling yet intractable therapeutic target. Using co-immunoprecipitation mass spectrometry, we uncovered an interaction between RAS and Argonaute 2 (AGO2). Endogenously, RAS and AGO2 co-sediment and co-localize in the endoplasmic reticulum. The AGO2 N-terminal domain directly binds the Switch II region of KRAS, agnostic of nucleotide (GDP/GTP) binding. Functionally, AGO2 knockdown attenuates cell proliferation in mutant KRAS-dependent cells and AGO2 overexpression enhances KRAS(G12V)-mediated transformation. Using AGO2-/- cells, we demonstrate that the RAS-AGO2 interaction is required for maximal mutant KRAS expression and cellular transformation. Mechanistically, oncogenic KRAS attenuates AGO2-mediated gene silencing. Overall, the functional interaction with AGO2 extends KRAS function beyond its canonical role in signaling.

Keywords: Argonaute 2; EIF2C2; KRAS; RNA silencing; cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Argonaute Proteins / antagonists & inhibitors
  • Argonaute Proteins / genetics*
  • Argonaute Proteins / metabolism
  • Base Sequence
  • Carboxypeptidases / genetics
  • Carboxypeptidases / metabolism
  • Cell Transformation, Neoplastic / genetics*
  • Cell Transformation, Neoplastic / metabolism
  • Cell Transformation, Neoplastic / pathology
  • Endoplasmic Reticulum / metabolism*
  • Gene Expression Regulation, Neoplastic*
  • Gene Silencing
  • Humans
  • Mice
  • MicroRNAs / genetics
  • MicroRNAs / metabolism
  • Molecular Sequence Data
  • Mutation
  • NIH 3T3 Cells
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / metabolism
  • Protein Binding
  • Proto-Oncogene Proteins p21(ras) / genetics*
  • Proto-Oncogene Proteins p21(ras) / metabolism
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Transgenes

Substances

  • AGO2 protein, human
  • Argonaute Proteins
  • KRAS protein, human
  • MicroRNAs
  • RNA, Small Interfering
  • Phosphatidylinositol 3-Kinases
  • Carboxypeptidases
  • SCPEP1 protein, human
  • Proto-Oncogene Proteins p21(ras)