HCMV Targets the Metabolic Stress Response through Activation of AMPK Whose Activity Is Important for Viral Replication
Figure 7
Impact of CaMKK inhibition on AMPK substrates.
Serum-starved MRC-5 human fibroblasts were mock infected or infected with HCMV (MOI = 3). After adsorption, cells were treated with the CaMKK inhibitor STO-609 (10 µg/ml) or DMSO (-). At 24, 48 and 72 h post infection cells harvested in lysis buffer and the resulting lysates were assayed for AMPK activity using the SAMS peptide as a substrate (A) or analyzed by Western blotting with antibodies specific for Ser79-pACC, ACC, TSC1, Glut4,Thr172-pAMPK, AMPK and tubulin (B). Relative pACC/ACC and Thr172-pAMPK/AMPK signal ratios in (B) were estimated during HCMV infection for DMSO and Compound C-treated cells using densitometry and subsequently normalized to the DMSO control. (C) At 40 h post infection, fresh media was added to all cells. At 58 h post infection, media was removed from mock and HCMV-infected fibroblasts and lactate secretion into the media over the 18 hr time frame was analyzed. All values are means + SE (n = 6).