Avian reovirus sigmaC protein induces apoptosis in cultured cells.
The avian reovirus (ARV) infection is associated with various disease conditions in poultry. However, the pathogenesis mechanisms are poorly characterized. In the present study, we clearly demonstrated that the sigmaC of ARV S1133 strain induced apoptosis in both BHK-21 and Vero cells. Five kinds of assays for apoptosis were used in analyzing ARV-infected BHK-21 and Vero cells: (1) assay for DNA ladders, (2) ELISA detection of cytoplasmic histone-associated DNA fragments, (3) nuclear staining with acridine orange, (4) Western blot, Northern blot, and immunofluorescent assay (IFA), and (5) flow cytometric analysis. The sigmaC protein of ARV could elicit apoptosis occurring in a dose- and time-dependent manner. The current results further our understanding of the function of sigmaC in cultured cells and suggest that sigmaC is a viral-encoded apoptin and possesses apoptosis-inducing ability. Furthermore, deletion analysis of the ARV sigmaC protein suggests that the carboxyl-terminus of sigmaC is important in mediating sigmaC-induced apoptosis because its deletion abolished the induction of apoptosis.
Shih
Wen L
WL
Department of Life Science, Tzu-Chi University, Hualien, Taiwan.
Hsu
Hsiao W
HW
Liao
Ming H
MH
Lee
Long H
LH
Liu
Hung J
HJ
D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D036022:Capsid Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D002460:Cell Line; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular; D006224:Cricetinae; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D017353:Gene Deletion; D007668:Kidney; D030101:Orthoreovirus, Avian / Q000737:chemistry / Q000472:pathogenicity / Q000502:physiology*; D013997:Time Factors; D014709:Vero Cells; D014774:Virulence
D036022:Capsid Proteins; C031728:sigma 1 protein, reovirus