Proteomic analysis of protein complexes in human SH-SY5Y neuroblastoma cells by using blue-native gel electrophoresis: an increase in lamin A/C associated with heat shock protein 90 in response to 6-hydroxydopamine-induced oxidative stress.

There is accumulating evidence that oxidative stress plays an important role in aging. Our previous phosphoproteomic study of the human neuroblastoma cell line SH-SY5Y revealed changes in the phosphorylation of several proteins such as lamin A/C during 6-hydroxydopamine-induced oxidative stress. The present study employed native proteomic analysis to clarify protein-protein interaction under physiological conditions. We examined oxidative stress-related changes in SH-SY5Y cellular proteins using blue-native polyacrylamide gel electrophoresis (BN-PAGE), a powerful tool for the separation of protein complexes. BN-PAGE gel images showed successful separation of several complexes. Components of these complexes, separated by 2-D BN-PAGE in combination with SDS-PAGE, were identified by peptide mass fingerprinting employing MALDI-TOF MS and an MS/MS ion search on LC-MS/MS. TCP-1 complex, ATP synthase, and the complex of heat shock protein 90 with its client proteins such as pyruvate kinase were detected. Two dimensional BN-PAGE and Western blot analysis revealed an increase of lamin A/C associated with heat shock protein 90 in response to 6-OHDA-induced oxidative stress.