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M and N proteins of SARS coronavirus induce apoptosis in HPF cells

Gang Zhao1, Shu-Qun Shi, Ying Yang

  • 1State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100080, China.

Cell Biology and Toxicology
|July 18, 2006
PubMed
Abstract

Insights

Severe acute respiratory syndrome coronavirus (SARS-CoV) structural proteins M and N induce apoptosis in human pulmonary fibroblast cells. Co-expression of M and N proteins significantly enhances this apoptotic effect, highlighting their role in SARS-CoV pathogenesis.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • Severe acute respiratory syndrome coronavirus (SARS-CoV) is known to induce apoptosis.
  • The role of specific SARS-CoV structural proteins in this process requires further investigation.

Purpose of the Study:

  • To investigate whether the M and N structural proteins of SARS-CoV can induce apoptosis.
  • To assess the combined effect of M and N proteins on apoptosis induction.

Main Methods:

  • Human pulmonary fibroblast (HPF) cells were transfected with plasmids encoding the M or N genes.
  • Apoptosis was assessed using TdT-mediated dUTP nick end labeling (TUNEL) and Hoechst 33342 staining.
  • Cell morphology was observed to identify apoptotic characteristics.

Main Results:

  • Transfection with M or N genes individually led to a significant increase in apoptotic cells compared to mock-transfected cells.
  • Co-transfection with both M and N genes resulted in a substantially higher percentage of apoptotic cells.
  • Statistical analysis confirmed significant differences between single-protein transfection and co-transfection groups.

Conclusions:

  • The M and N structural proteins of SARS-CoV are capable of inducing apoptosis in HPF cells.
  • Co-expression of M and N proteins potentiates the apoptotic effect, suggesting a synergistic role.
  • These findings indicate that SARS-CoV structural proteins play a crucial role in viral invasion and the pathogenetic process within host cells.

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