Adaptor linked K63 di-Ubiquitin activates Nedd4/Rsp5 E3 ligase
Nedd4/Rsp5 family E3 ligases mediate numerous cellular processes, many of which require the E3 ligase to interact with PY-motif containing adaptor proteins. Several Arrestin-Related Trafficking adaptors (ARTs) of Rsp5 were self-ubiquitinated for activation, but the regulation mechanism remains elusive. Remarkably, we demonstrate that Art1, Art4, and Art5 undergo K63 linked di-Ubiquitination by Rsp5. This modification enhances the PM recruitment of Rsp5 by Art1 or Art5 upon substrate induction, required for cargo protein ubiquitination. In agreement with these observations, we find that di-ubiquitin strengthens the interaction between the Pombe orthologs of Rsp5 and Art1, Pub1 and Any1. Further, we discover that the HECT domain exosite protects the K63 linked di-Ubiquitin on the adaptors from cleavage by the deubiquitination enzyme Ubp2. Together, our study uncovers a novel ubiquitination modification implemented by Rsp5 adaptor proteins, underscoring the regulatory mechanism of how adaptor proteins control the recruitment and activity of Rsp5 for the turnover of membrane proteins.
All data generated or analysed during this study are included in the manuscript. Source Data files have been provided for figures.
Article and author information
Cornell University (CU563704)
- Scott D Emr
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Wade Harper, Harvard Medical School, United States
- Preprint posted: November 26, 2021 (view preprint)
- Received: January 28, 2022
- Accepted: June 8, 2022
- Accepted Manuscript published: June 30, 2022 (version 1)
- Version of Record published: July 14, 2022 (version 2)
© 2022, Zhu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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