Our experiments have shown that the viral DNA replication inhibitor ACG completely abolished the HSV 1 mediated induction of TAp63�� in SIRC cells, indicating that replication of viral DNA is necessary for the accumulation of TAp63��. This observation strongly supports the view that the dysregulation of Rucaparib structure p63 expression depends on the cellular DDR, but does not exclude the role of HSV 1 encoded proteins. Thus, additional studies are required to eluci date the potential contributions of vhs, TIF, ICP0 and other viral proteins to the development of the HSV 1 mediated dysregulation of p63 expression. Our data fur ther demonstrated that HSV 1 infected SIRC cells display decreased viability and an increased apoptotic rate.
Together, these results suggest that the altered pattern of p63 expression observed in HSV 1 infected SIRC cells may represent a mechanism by which this virus perturbs the functions of the corneal epithelial cells and leads to their demise. Inhibitors,Modulators,Libraries In line with these data, we next investigated the expres sion of Bax, which is known to be upregulated by TAp63 and TAp63��. Previous studies have demonstrated the existence of several Bax isoforms. It is well docu mented that Bax is a central component of apoptosis induction. In response to apoptotic stimuli, Bax becomes activated, translocates to the mitochondria and triggers the release of cytochrome c and caspase 9, which in turn results in the irreversible execution of the apop totic program. It has been reported that the Bax B protein is expressed constitutively in several human cell types, and its level is controlled by proteasomal degrada tion.
Various stressors inhibit ubiquitination of the Bax B protein and thereby prevent its proteasomal degra Inhibitors,Modulators,Libraries dation, leading to the accumulation of this Bax isoform. Similarly to Bax, Bax B has the capability to trig ger apoptosis via the mitochondrial pathway. Moreover, Bax B associates with and promotes Bax activation. Our experiments revealed no constitutive expression of any of the Bax isoforms in the mock infected SIRC cells. Interestingly, we observed Inhibitors,Modulators,Libraries a dramatic rise in the level of Bax B in HSV 1 infected cul tures. Following the demonstration of an altered Bax expression pattern in SIRC cells, we postulate an important role for Bax B in the apoptotic responsiveness of corneal epithelial cells infected with HSV 1.
Other interesting Inhibitors,Modulators,Libraries recent data have proved that HSVs encode ubiquitinating and deubiquitinating enzymes, which can modify the ubiquitination status of both viral and host cell proteins. In view of these observations, it is reasonable Inhibitors,Modulators,Libraries to infer that the Bax B protein may be a novel target of HSV 1 mediated deubiquitinating events. find more information How ever, the precise molecular mechanisms responsible for stabilization of the Bax B protein in HSV 1 infected cells remain to be elucidated. Conclusions Overall, this study demonstrates that the KOS strain of HSV 1 modulates the patterns of p63 and Bax expression in the SIRC cell line.