2026-10-11T16:50:37Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34025270 2026-09-29T17:03:53Z category_1 category_4 category_915 category_7 category_12 category_14 category_46 category_69 category_132 category_133 portal_63 item_type_3 month_year_09_2026

Cooperative Membrane Recognition by Lipid-Sensing and Kinase Domains Shapes Membrane-Bound States of AKT Yuki Nakagaki (25138004) Toshiki Mori (5982395) Kenichi G. N. Suzuki (9444191) Eiji Yamamoto (113384) Biophysics Biochemistry Physical Sciences not elsewhere classified Medicine Cell Biology Molecular Biology Immunology Inorganic Chemistry Infectious Diseases Plant Biology threonine kinase composed terminal pleckstrin homology 5 )- trisphosphate providing molecular insight membranes remains unclear secondary binding site terminal kinase domain regulate akt activation akt signaling pathway binding modes depend cooperative membrane recognition 3 </ sub observed specific pip akt membrane recruitment binding modes molecular level cellular membranes cooperative roles cooperative contributions residence membrane membrane recruitment membrane contacts supports distinct stable mode stabilizes longer multidomain serine molecule imaging findings suggest domains cooperate cell single bound states basic residues The PI3K/AKT signaling pathway is triggered by the recruitment of AKT to cellular membranes. Although AKT is a multidomain serine/threonine kinase composed of an N-terminal pleckstrin homology (PH) domain and a C-terminal kinase domain (KD), how these domains cooperate to regulate AKT activation on membranes remains unclear at the molecular level. Here, using molecular dynamics simulations of full-length AKT on phosphatidylinositol (3,4,5)-trisphosphate (PIP₃)-containing lipid bilayers, we identify four distinct membrane-binding modes that differ in the orientations and membrane contacts of the PH domain and KD. In addition to PIP₃ binding to the PH domain, we observed specific PIP₃ interactions with basic residues in the KD. In the most stable mode, PIP₃ interacts with both the canonical and a secondary binding site in the PH domain, while the KD adopts an orientation in which the activation loop phosphorylation site is exposed to the solvent. The populations of these binding modes depend on the PIP₃ concentration in the membrane, leading to changes in the preferred orientation of AKT. Live-cell single-molecule imaging further supports distinct but cooperative roles of the PH domain and KD in membrane recruitment: the PH domain primarily promotes membrane association, whereas the KD enhances recruitment efficiency and stabilizes longer-residence membrane-bound states. These findings suggest that AKT membrane recruitment is governed by cooperative contributions from both the PH domain and the KD, providing molecular insight into how AKT is positioned and stabilized on PIP₃-containing membranes. 2026-09-29T00:00:00Z Dataset Dataset 10.1021/jacs.6c13162.s001 https://figshare.com/articles/dataset/Cooperative_Membrane_Recognition_by_Lipid-Sensing_and_Kinase_Domains_Shapes_Membrane-Bound_States_of_AKT/34025270 CC BY-NC 4.0