The structural determinants of PH domain-mediated regulation of Akt revealed by segmental labeling

TY - JOUR

T1 - The structural determinants of PH domain-mediated regulation of Akt revealed by segmental labeling

AU - Chu, Nam

AU - Viennet, Thibault

AU - Bae, Hwan

AU - Salguero, Antonieta

AU - Boeszoermenyi, Andras

AU - Arthanari, Haribabu

AU - Cole, Philip A.

N1 - Publisher Copyright: © Chu et al.

PY - 2020/8

Y1 - 2020/8

N2 - Akt is a critical protein kinase that governs cancer cell growth and metabolism. Akt appears to be autoinhibited by an intramolecular interaction between its N-terminal pleckstrin homology (PH) domain and kinase domain, which is relieved by C-tail phosphorylation, but the precise molecular mechanisms remain elusive. Here, we use a combination of protein semisynthesis, NMR, and enzymological analysis to characterize structural features of the PH domain in its autoinhibited and activated states. We find that Akt autoinhibition depends on the length/flexibility of the PH-kinase linker. We identify a role for a dynamic short segment in the PH domain that appears to regulate autoinhibition and PDK1-catalyzed phosphorylation of Thr308 in the activation loop. We determine that Akt allosteric inhibitor MK2206 drives distinct PH domain structural changes compared to baseline autoinhibited Akt. These results highlight how the conformational plasticity of Akt governs the delicate control of its catalytic properties.

AB - Akt is a critical protein kinase that governs cancer cell growth and metabolism. Akt appears to be autoinhibited by an intramolecular interaction between its N-terminal pleckstrin homology (PH) domain and kinase domain, which is relieved by C-tail phosphorylation, but the precise molecular mechanisms remain elusive. Here, we use a combination of protein semisynthesis, NMR, and enzymological analysis to characterize structural features of the PH domain in its autoinhibited and activated states. We find that Akt autoinhibition depends on the length/flexibility of the PH-kinase linker. We identify a role for a dynamic short segment in the PH domain that appears to regulate autoinhibition and PDK1-catalyzed phosphorylation of Thr308 in the activation loop. We determine that Akt allosteric inhibitor MK2206 drives distinct PH domain structural changes compared to baseline autoinhibited Akt. These results highlight how the conformational plasticity of Akt governs the delicate control of its catalytic properties.

UR - http://www.scopus.com/inward/record.url?scp=85089768636&partnerID=8YFLogxK

U2 - 10.7554/ELIFE.59151

DO - 10.7554/ELIFE.59151

M3 - Journal article

C2 - 32744507

AN - SCOPUS:85089768636

SN - 2050-084X

VL - 9

SP - 1

EP - 23

JO - eLife

JF - eLife

M1 - e59151

ER -