A wide variety of other proteins, including caspase-3, and bcl-2 family members (bcl2, bclX, MCL1, BAK, BAX, BIM, BAD) showed wide variations in expression among the different viral infections.
Further study displayed that the potential mechanisms mainly relied on regulation of the expressions of pro-apoptotic protein Bax and anti-apoptotic Bcl-2, thus speeding up the process of IBDV-infected cell apoptosis and preventing virus infection.
Here we review the structural biology, interactions, and mechanisms of action of virus-encoded Bcl-2 proteins, and how they impact on host-virus interactions to ultimately enable successful establishment and propagation of viral infections.
The B-cell lymphoma 2 (Bcl-2) proteins family is the main arbiter of mitochondrially mediated apoptosis, and viruses have evolved sequence and structural mimics of Bcl-2 to subvert premature host cell apoptosis in response to viral infection.
However, the expression of the inhibitory apoptosis protein B-cell lymphoma 2 (bcl-2) did not change, but bcl-2-associated X/bcl-2 ratio was higher in the rL-RVG group than that in the NDV group.
BCL-2 gene polymorphism at codon 43 (127G/A) has been found to be a reliable and sensitive marker for the prediction of response to interferon therapy during viral infections.
The increase in Bcl-2 levels seems to be controlled by the virus infection itself and results in the establishment of long-term, persistently infected cultures that continue to produce virus.
Thus, exploring the biochemical and biological functions of the viral BCL-2 family proteins will increase our understanding of their role in virus infections and will undoubtedly teach us something about their cellular kin.
The significance of low bcl-2 expression by CD45RO T cells in normal individuals and patients with acute viral infections. The role of apoptosis in T cell memory.
Thus cellular bcl-2 oncogene expression plays a role in the establishment of persistent viral infection by blocking virus-induced programmed cell death.