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bioRxiv · 10.1101/2022.04.14.488377

The E3/E4 ubiquitin ligase UFD-2 mediates negative feedback on Raf protein stability

Townley, R.·Deniaud, A.·Stacy, K. S.·Rodriguez Torres, C. S.·Cheraghi, F.·de la Cova, C. C.
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Abstract

Signaling by the kinase cascade comprised of Raf, MEK, and ERK is critical for animal development; moreover, its inappropriate activation is commonly found in human malignancies. In a genetic screen for factors that control signaling by the Caenorhabditis elegans Raf ortholog LIN-45, we found that it is negatively regulated by the E3/E4 ubiquitin ligase UFD-2. Both UFD-2 and its partner, the ATP-dependent unfoldase CDC-48, were required for degradation of LIN-45 protein. Our structure-function studies showed that disruption of LIN-45 domains that mediate protein interactions and complex formation, including the Ras binding domain, cysteine-rich domain, or C-terminus, allow for UFD-2-independent degradation. We propose a model whereby UFD-2 mediates a novel step of Raf degradation, by acting with the CDC-48 unfoldase machinery to extract Raf from multiprotein complexes. One-Sentence SummaryRaf kinase complexes are degraded by the UFD-2 ubiquitin ligase and CDC-48 unfoldase during Raf-MEK-ERK signal transduction.

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Townley, R., Deniaud, A., Stacy, K. S., Rodriguez Torres, C. S., Cheraghi, F., de la Cova, C. C.. 2022-04-15. The E3/E4 ubiquitin ligase UFD-2 mediates negative feedback on Raf protein stability. https://doi.org/10.1101/2022.04.14.488377

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