Expression of the selectable marker gene bsrm in BALB/MK cells induces apoptosis by overproduction of hydrogen peroxide

• Autor(a) principal: Takeshita, Daniela
• Data de Publicação: 2007
• Outros Autores: Bento, Fernanda Mara, Chammas, Roger, Belizario, Jose Ernesto, Carmona, Adriana Karaoglanovic, Konno, Katsuhiro, Melo, Robson Lopes de, Molina, Gustavo, Lisboa, Bianca Cristina Garcia, Han, Sang Won [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://repositorio.unifesp.br/handle/11600/30058; http://dx.doi.org/10.1139/O07-058
• topic: selectable marker; apoptosis; hydrogen peroxide; blasticidin S.

Transduction of the retroviral vector LBmSN, which expresses the blasticidin S resistance gene bsrm in the murine keratinocyte cell line BALB/MK, induces death in these cells. Cell death is caused by a factor called DOKEB (death factor obtained from keratinocytes expressing bsrm), which is released before the cells' death. in this report we describe and discuss the purification and characterization of DOKEB. Our results were as follows. (i) the 5-day-old medium from the modified BALB/MK cells with LBmSN was used for purification and characterization by filtration and chromatography: DOKEB was a stable and highly hydrophilic compound, with a molecular mass less than that of I amino acid. (ii) the conditioned medium containing DOKEB was reactive against thiobarbituric acid and dichlorofluorescein diacetate. (iii) DOKEB activity was neutralized by the incubation of the conditioned medium with catalase. Therefore, our conclusion is that the BALB/MK cells expressing bsrm produce a large amount of hydrogen peroxide, which catalyzes the process of apoptosis of those cells.