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Oligopeptide Competition Assay for Phosphorylation Site Determination
Published on: May 18, 2017
Phosphorylation of AKT: a mutational analysis.
Jonathan R Hart1, Peter K Vogt
1The Scripps Research Institute, Molecular and Experimental Medicine, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. jhart@scripps.edu
Oncotarget
|June 15, 2011
Summary
Phosphorylation of Akt at T308 and S473 is crucial for cell proliferation and apoptosis resistance, key aspects of oncogenic transformation. T450 phosphorylation plays a minimal role in these processes.
Area of Science:
- Molecular Biology
- Cellular Signaling
- Oncogenesis
Background:
- The Akt signaling pathway, regulated by phosphatidylinositol 3-kinase (PI3K), is vital for cell growth, differentiation, and apoptosis.
- Aberrant Akt activation contributes to uncontrolled cell proliferation and apoptosis resistance, characteristic of cancer.
Purpose of the Study:
- To investigate the roles of Akt phosphorylation at T308, S473, and T450 in oncogenic transformation and signaling.
- To elucidate the distinct functions of T308 and S473 phosphorylation in cellular processes.
Main Methods:
- Site-directed mutagenesis to create inactivating and phosphomimetic mutations at Akt residues T308, S473, and T450.
- Analysis of cellular proliferation, apoptosis, and signaling pathways in response to these mutations.
Main Results:
- Phosphorylation at T450 exhibits minimal impact on oncogenic transformation and signaling.
- Phosphorylation at T308 and S473 are essential for distinct, non-overlapping functions in cell proliferation and apoptosis regulation.
- Mutational analysis revealed specific roles for T308 and S473 phosphorylation in cellular transformation.
Conclusions:
- T308 and S473 phosphorylation sites on Akt are critical regulators of oncogenic transformation, with distinct functional contributions.
- Targeting T308 and S473 phosphorylation may offer therapeutic strategies for cancers driven by Akt pathway activation.
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