Drosophila PI3 kinase and Akt involved in insulin-stimulated proliferation and ERK pathway activation in Schneider cells.
We have characterized the role of Drosophila PI3K and AKT in ERK pathway activation involving insulin-induced proliferation using Drosophila Schneider cells. After insulin treatment, dPI3K and dAKT activities were both increased along with activation of the dERK pathway components dMEK and dERK. The insulin-induced activations of dERK and dAKT were blocked by LY294002, dPTEN, and by an AKT inhibitor, indicating involvement of dPI3K and dAKT in the insulin-induced dERK and dAKT activations. Proliferation and the G1 to S phase cell cycle progression due to insulin were also blocked by PI3K and AKT inhibitors, indicating that the Drosophila PI3K-AKT pathway involves insulin-mediated cell proliferation. The insulin-stimulated size increase was blocked by both LY294002 and AKT inhibitor, not by U0126, indicating that insulin-mediated size control by dPI3K and dAKT occurs independently of the ERK pathway. This study indicates that dPI3K and dAKT are involved in insulin-induced ERK pathway activation leading to proliferation in Drosophila Schneider cells.
Kim
Sung-Eun
SE
Department of Biotechnology, Division of Cellular and Molecular Biology, Yonsei University, 132 Shinchon-Dong, Seodemun-Gu, Seoul 120-752, South Korea.
Cho
Jae-Young
JY
Kim
Kyung-Sup
KS
Lee
Su-Jae
SJ
Lee
Ki-Hoo
KH
Choi
Kang-Yell
KY
D000818:Animals; D002453:Cell Cycle / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster; D004791:Enzyme Inhibitors / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000187:drug effects / Q000378:metabolism*; D016193:G1 Phase / Q000187:drug effects / Q000502:physiology; D007328:Insulin / Q000378:metabolism* / Q000494:pharmacology; D048369:MAP Kinase Kinase 1 / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt; D016196:S Phase / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
D029721:Drosophila Proteins; D004791:Enzyme Inhibitors; D048049:Extracellular Signal-Regulated MAP Kinases; D007328:Insulin; D048369:MAP Kinase Kinase 1; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; C494917:Akt1 protein, Drosophila