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Accelerated induction of apoptosis in insect cells by baculovirus-expressed SARS-CoV membrane protein.

ABSTRACT: It has been shown that severe acute respiratory syndrome-associated coronavirus (SARS-CoV) 3a and 7a proteins, but not membrane (M) protein, induce apoptosis in mammalian cells. Upon expression of SARS-CoV M protein using the baculovirus/insect cell expression system, however, we found that the expressed M protein triggered accelerated apoptosis in insect cells, as characterized by rapid cell death, elevated cytotoxicity, cell shrinkage, nuclear condensation and DNA fragmentation. Conversely, the M protein expressed in mammalian cells did not induce apoptosis. This is the first report describing the induction of apoptosis by SARS-CoV M protein in animal cells and possible implications are discussed.

SUBMITTER: Lai CW

PROVIDER: S-EPMC7094299 | biostudies-literature |

REPOSITORIES: biostudies-literature

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