Carbamoyl Phosphate Synthetase I이 요소회로 유전자를 발현하는 CHO 세포 주의 세포 성장과 재조합 Erythropoietin의 생산에 미치는 영향

Effects of Carbamoyl Phosphate Synthetase I against Cell Growth and Production of Recombinant Erythropoietin in Urea Cycle Enzyme Expressing CHO Cell Line

In the previous reports, we developed the CO5 by introducing genes for the first and second urea cycle enzymes, carbamoyl phosphate synthetase I (CPS I) and ornithine transcarbamoylase (OTC) into the IBE cell lines producing erythropoietin (EPO). The CO5 have been found out to have 15~20% higher cell growth rate and produce 2-times more EPO than the parental cell line, IBE. To investigate the rele of CPS I in CO5 cell line for the cell growth and amount of EPO, we knock-downed CPS I gene expression via siRNA treatment. Expression level of IPO in cell lysate of CO5 was 3~5 fold higher than that of IBE. After siRNA treatment, the cell growth of CO5 was decreased 8~21% and the EPO productivity in the cell lysate was significantly decreased. However, these changes of the cell growth and EPO productivity were not observed in IBE. These results indicate that CPS I gene expression is important for the increased cell growth and EPO productivity of CO5 cell line.