KRAS Engages AGO2 to Enhance Cellular Transformation

Abstract

SUMMARY 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 KRASG12V-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.

Resolving Subcellular miRNA Trafficking and Turnover at Single-Molecule Resolution

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A novel method to accurately locate and count large numbers of steps by photobleaching

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“…, 2012, 2014, 2013; Shankar et al. , 2016), using a home-built IX-81 Olympus microscope with a 60×, 1.49 numerical aperture oil immersion objective (Olympus, Lombard, IL), 2× magnification wheel, P–545.3C7 capacitive piezoelectric xyz -stage (Physik Instrumente, Karlsruhe, Germany), iXon 897 (Andor, Belfast, United Kingdom) electron-multiplying charge-coupled device camera, and a Cell-TIRF module (Olympus).…”

An Essential Role forArgonaute 2in EGFR-KRAS Signaling in Pancreatic Cancer Development

“…To investigate potential additional modulators of RAS-mediated oncogenesis, we previously performed a screen for direct interactors of RAS in a panel of cancer cell lines and identified a direct interaction between KRAS and Argonaute 2 (AGO2), independent of KRAS mutation status 15 . The N-terminal domain of AGO2 was found to bind the regulatory Switch II region in RAS and was required for oncogenic KRAS-driven cellular transformation.…”