FIGURE 1.

CaMKII activation is sensitive to metabolic status. A, Xenopus egg extracts were treated with or without G6P for 0. 5 h at room temperature and analyzed for CaMKII Thr²⁸⁶ autophosphorylation using a Thr(P)²⁸⁶ antibody. Note that the middle and bottom panels are from two different films as the CaMKII antibody recognized CaMKIIα (∼50 kDa) much more strongly than the other isoforms, so detection of this isoform and the others required very different exposures. B, GST tagged Xenopus caspase-2 prodomain or GST bound to glutathione-Sepharose was incubated with Xenopus egg extracts supplemented with [γ-³²P]ATP and treated with or without G6P. Samples were resolved by SDS-PAGE and detected by autoradiography. CB, Coomassie Blue. C, glucose-starved 293T cells treated with or without glucose (25 mm) were lysed and analyzed for CaMKII Thr²⁸⁶ autophosphorylation. D, glucose-starved 293T cells treated with or without glucose and with or without dehydroepiandrosterone (DHEA) were lysed and analyzed for CaMKII Thr²⁸⁶ autophosphorylation.