PH domain-mediated autoinhibition and oncogenic activation of Akt
Abstract
Akt is a Ser/Thr protein kinase that plays a central role in metabolism and cancer. Regulation of Akt's activity involves an autoinhibitory intramolecular interaction between its pleckstrin homology (PH) domain and its kinase domain that can be relieved by C-tail phosphorylation. PH domain mutant E17K Akt is a well-established oncogene. Previously, we reported that the conformation of autoinhibited Akt may be shifted by small molecule allosteric inhibitors limiting the mechanistic insights from existing X-ray structures that have relied on such compounds (Chu, Viennet, et al, 2020). Here we discover unexpectedly that a single mutation R86A Akt exhibits intensified autoinhibitory features with enhanced PH domain-kinase domain affinity. Structural and biochemical analysis uncovers the importance of a key interaction network involving Arg86, Glu17, and Tyr18 that controls Akt conformation and activity. Our studies also shed light on the molecular basis for E17K Akt activation as an oncogenic driver.
Data availability
Diffraction data have been deposited in PDB under the accession code: 7MYXSource data are uploaded as Zip files on the eLife website
Article and author information
Author details
Funding
National Cancer Institute (R01CA74305)
- Philip A Cole
National Cancer Institute (R35CA242461)
- Michael J Eck
National Cancer Institute (K22CA241105)
- Nam Chu
Claudia Adams Barr Program (Grant)
- Haribabu Arthanari
National Institutes of Health (EB002026)
- Haribabu Arthanari
Kwanjeong Education Foundation (Fellowship)
- Hwan Bae
National Institute of General Medical Sciences (GM124165)
- Michael J Eck
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Bae 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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