Mild electrical stimulation increases ubiquitinated proteins and Hsp72 in A549 cells via attenuation of proteasomal degradation.
To explore the cellular effects of mild electrical stimulation (MES), we treated A549 cells with low-intensity direct current at 5 V applied for 10 min. MES did not induce cell cytotoxicity or the unfolded protein response (UPR). Interestingly, the expression of ubiquitinated proteins and heat shock protein (Hsp) 72 was increased but not that of other Hsps. MES attenuated the degradation of Hsp72, which is a substrate of the proteasome-ubiquitin system. These results, along with the observed increase in expression of ubiquitinated proteins, imply that MES may affect the proteasome system, which regulates the fate of many proteins.
Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Global COE "Cell Fate Regulation Research and Education Unit", Kumamoto University, 5-1 Oe-honmachi, Kumamoto, Japan.
Saori
S
Morino
Mary Ann
MA
Suico
Tatsuya
T
Kondo
Erika
E
Sekimoto
Shuichiro
S
Yano
Tomoko
T
Matsuda
Takashi
T
Matsuno
Tsuyoshi
T
Shuto
Eiichi
E
Araki
Hirofumi
H
Kai
D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D004558:Electric Stimulation; D050884:HSP72 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008175:Lung Neoplasms / Q000201:enzymology / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D061988:Proteasome Inhibitors; D011499:Protein Processing, Post-Translational; D013997:Time Factors; D025801:Ubiquitin / Q000378:metabolism*; D015854:Up-Regulation
D050884:HSP72 Heat-Shock Proteins; D061988:Proteasome Inhibitors; D025801:Ubiquitin; D007770:L-Lactate Dehydrogenase; D046988:Proteasome Endopeptidase Complex; D002118:Calcium