A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Finnish-specific AKT2 gene variant leads to impaired insulin signalling in myotubes
Tekijät: Mäkinen Selita, Datta Neeta, Rangarajan Savithri, Nguyen Yen H., Olkkonen Vesa M., Latva-Rasku Aino, Nuutila Pirjo, Laakso Markku, Koistinen Heikki A.
Julkaisuvuosi: 2023
Journal: Journal of Molecular Endocrinology
Tietokannassa oleva lehden nimi: Journal of molecular endocrinology
Lehden akronyymi: J Mol Endocrinol
Artikkelin numero: e210285
Vuosikerta: 70
Numero: 2
ISSN: 0952-5041
eISSN: 1479-6813
DOI: https://doi.org/10.1530/JME-21-0285
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/178245413
Finnish-specific gene variant p.P50T/AKT2 (minor allele frequency (MAF) = 1.1%) is associated with insulin resistance and increased predisposition to type 2 diabetes. Here, we have investigated in vitro the impact of the gene variant on glucose metabolism and intracellular signalling in human primary skeletal muscle cells, which were established from 14 male p.P50T/AKT2 variant carriers and 14 controls. Insulin-stimulated glucose uptake and glucose incorporation into glycogen were detected with 2-[1,2-3H]-deoxy-D-glucose and D-[14C]-glucose, respectively, and the rate of glycolysis was measured with a Seahorse XFe96 analyzer. Insulin signalling was investigated with Western blotting. The binding of variant and control AKT2-PH domains to phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3) was assayed using PIP StripsTM Membranes. Protein tyrosine kinase and serine-threonine kinase assays were performed using the PamGene® kinome profiling system. Insulin-stimulated glucose uptake and glycogen synthesis in myotubes in vitro were not significantly affected by the genotype. However, the insulin-stimulated glycolytic rate was impaired in variant myotubes. Western blot analysis showed that insulin-stimulated phosphorylation of AKT-Thr308, AS160-Thr642 and GSK3β-Ser9 was reduced in variant myotubes compared to controls. The binding of variant AKT2-PH domain to PI(3,4,5)P3 was reduced as compared to the control protein. PamGene® kinome profiling revealed multiple differentially phosphorylated kinase substrates, e.g. calmodulin, between the genotypes. Further in silico upstream kinase analysis predicted a large-scale impairment in activities of kinases participating, for example, in intracellular signal transduction, protein translation and cell cycle events. In conclusion, myotubes from p.P50T/AKT2 variant carriers show multiple signalling alterations which may contribute to predisposition to insulin resistance and T2D in the carriers of this signalling variant.
Ladattava julkaisu This is an electronic reprint of the original article. |  |
