earticle

영어

Maintenance of mitochondria integrity by overexpression of Bcl-2, a typical anti-apoptotic protein, is a critical point in recombinant Chinese hamster ovary (rCHO) cell culture treated with sodium butyrate (NaBu) known as a typical specific productivity-enhancing factor. Bcl-2 distributes and functions in multiple intracellular organelles such as nucleus, mitochondria, and ER. To evaluate the effect of organelle -specific overexpression of Bcl-2 on NaBu-induced apoptosis, Bcl-2 expression was restricted at mitochondria or ER by employing mitochondrial insertion sequence of ActA or ER-specific sequence of cytochrome b5 to its sequence. The rCHO cell lines over -expressing mitochondrial Bcl-2 (MT-Bcl-2) or ER-targeted Bcl-2 (ER-Bcl-2) were established. Overexpression of MT-Bcl-2 or ER-Bcl-2 could increase cell viability and decrease LDH release under NaBu-treated condition. Also, it could suppress NaBu-induced apoptosis as evidenced from DNA fragmentation assay. Mitochondria membrane potential assay revealed that ER-Bcl-2 overexpression can maintain the mitochondria membrane integrity without helping MT-Bcl-2 overexpression, indicating the role of ER should be considered in alleviating NaBu-induced apoptosis by genetic modulation strategy. Taken together, it was found that restricted Bcl-2 overexpression at ER could inhibit the NaBu-induced apoptosis via maintaining mitochondria integrity in rCHO cells.