Initiation factor eIF2B not p70 S6 kinase is involved in the activation of the PI‐3K signalling pathway induced by the v‐src oncogene

FEBS Letters

Kučerová, Dana¹  Jiřička, Jaroslav¹  Sovová, Vlasta¹  Šloncová, Eva¹  Vojtěchová, Martina¹  Tuháčková, Zdena¹ 

[1] Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, 16637 Prague 6, Czech Republic

关键词: Phosphoinositide 3′-kinase signalling pathway;    mRNA translation;    70-kDa Ribosomal protein S6 kinase;    v-Src transformation;    Initiation factor eIF2B;    RSV;    Rous sarcoma virus;    PI-3K;    phosphoinositide 3′-kinase;    mTOR;    mammalian target of rapamycin;    eIF;    eukaryotic initiation factor;    4E-BP1;    eukaryotic initiation factor 4E-binding protein;    GSK-3;    glycogen synthase kinase 3;    p70 S6k;    70-kDa ribosomal protein S6 kinase;   

DOI  :  10.1016/S0014-5793(03)00415-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Our data show that in hamster fibroblasts transformed by Rous sarcoma virus (RSV), the phosphoinositide 3′-kinase (PI-3K)/Akt/glycogen synthase kinase 3 antiapoptotic pathway is upregulated and involved in increased protein synthesis through activation of initiation factor eIF2B. Upon inhibition of PI-3K by wortmannin, phosphorylation of 70-kDa ribosomal protein S6 kinase (p70 S6k) and its physiological substrate, ribosomal protein S6, decreased in the non-transformed cells but not in RSV-transformed cells. Thus PI-3K, which is thought to be involved in regulation of p70 S6k, signals to p70 S6k in normal fibroblasts, but it does not appear to be an upstream effector of p70 S6k in fibroblasts transformed by v-src oncogene, suggesting that changes in the PI-3K signalling pathway upstream of p70 S6k are induced by RSV transformation.

【 授权许可】

Unknown