Reduced eIF2α phosphorylation and increased proapoptotic proteins in aging
Section snippets
Materials
Wistar rats were kept under standard conditions of light and temperature and fed ad libitum access on commercial rat chow and water. All experiments were carried out according to the Committee for the Purpose of Control and Supervision of Experiments on Animals (CPCSEA), Government of India, guidelines. The antibodies are obtained from Cell Signaling Technologies (eIF4E, phospho-eIF4E, phospho-4EBP’s, S6, and phospho-S6), Research Genetics (phospho-eIF2α), Calbiochem (GRP-78/BiP), Sigma
Initiation factors and their phosphorylation are reduced during aging
Relative levels of several eukaryotic initiation factors (eIFs) viz., eIF2α, eIF2Bε, eIF5, eIF4E (Fig. 1), and S6, a 40S ribosomal protein (Fig. 1), and also the phosphorylation of eIF2α, eIF4E, S6, and eIF4E binding proteins (eIF4E BPs) (Fig. 2) reduced during aging in different rat tissues. The reduction in the abundance of ribosomes as measured from S6 levels and in translational factors during aging is consistent with the previous observations that translation decreases with aging [1], [25]
Acknowledgments
K.V.A.R. thanks ICMR, New-Delhi for financial support of a Project 52/6/99-BMS and S.H. thanks UGC for a fellowship.
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