The ion channel activity of the SARS-coronavirus 3a protein is linked to its pro-apoptotic function

摘要: The severe acute respiratory syndrome-coronavirus (SARS-CoV) caused an outbreak of atypical pneumonia in 2003. SARS-CoV viral genome encodes several proteins which have no homology to any other coronaviruses, and a number these been implicated cytopathies. One such protein is 3a, also known as X1, ORF3 U274. 3a expression detected both infected cultured cells patients. Among the different functions identified, capable inducing apoptosis. We previously showed that caspase pathways are involved 3a-induced In this study, we attempted find out domains on essential for its pro-apoptotic function. Protein sequence analysis reveals possesses three major signatures, cysteine-rich, Yxx phi diacidic domains. carrying respective mutations exhibit reduced activities, indicating importance 3a's It was reported potassium ion channel activity. further demonstrated blockade activity abolished caspase-dependent This report provides first evidence required As has regulate apoptosis pathologic conditions, finding ways modulate may offer new direction toward inhibition triggered by SARS-CoV.