This is the first demonstration of such a promoter. late transcription factor/antioxidant response element (MLTF/ARE), the STAT3 binding site around the upstream promoter, and the glucocorticoid responsive element (gene, in the induction process in the liver and lung. In the lung, inducible footprinting was also identified at a unique gamma interferon (IFN-) response element (-IRE) and at Sp1 sites. The mobility shift analysis showed activation of STAT3 and the glucocorticoid receptor in the liver and lung nuclear extracts, which was consistent with the IVGF data. Analysis of the newly synthesized mRNA for cytokines in the infected lung by real-time PCR showed a robust increase in the levels of IL-10 and IFN- mRNA that can activate STAT3 and STAT1, respectively. A STAT1-made up of complex that binds to the -IRE in vitro was activated in the infected lung. No major change in MLTF/ARE DNA binding activity in the liver and lung occurred after contamination. These results have exhibited that MT-I and MT-II can be induced robustly in (24R)-MC 976 the liver and lung following experimental influenza virus contamination by overlapping but distinct molecular mechanisms. Viral contamination of the respiratory tract remains a leading cause of morbidity and mortality worldwide. Influenza virus contamination causes approximately 20,000 deaths and 110,000 hospitalizations per year in the United States (13). Influenza virus A is usually a member of the orthomyxovirus family of enveloped, segmented, negative-strand RNA viruses. This virus replicates in the epithelial cells lining the upper respiratory tract of humans and in both the upper and lower respiratory tract of mice. The infection and initial replication cycle stimulate the production and release of antiviral and proinflammatory cytokines such as alpha, beta, and gamma interferon (IFN) and interleukin-6 (IL-6) (32, 38). The cytokines limit viral replication as well as stimulate the innate immune response, leading (24R)-MC 976 to recruitment of activated monocytes/macrophages. These immune cells use a variety of mechanisms to limit viral replication until the host can generate a cell-mediated, antigen-specific response. One such mechanism involves macrophage phagocytosis, which generates reactive oxygen species. These oxygen species contribute to the immune-mediated pathology associated with the contamination. Successful resolution of the contamination requires viral clearance as well as restriction of immune-mediated damage. Experimental influenza virus contamination also induces expression of a set of cellular genes that include acute-phase proteins in the liver. Metallothionein I (MT-I) and MT-II are stress response proteins that are coordinately induced at a very high level in response to variety of pathological conditions, including inflammation, bacterial infection, restraint stress, anticancer drugs, heavy metals, and (24R)-MC 976 brokers that generate reactive oxygen species (for reviews, see references 5 and 21). The unique metal-thiolate bonds of these cysteine-rich, heavy-metal-binding proteins can scavenge most potent hydroxyl and other free radicals very efficiently (60, 64). MT-I and MT-II are expressed in all eukaryotes and are conserved throughout evolution, whereas the isoforms MT-III and MT-IV are expressed only in mammals (58). Unlike MT-I and MT-II, which (24R)-MC 976 are ubiquitous (21, 53), MT-III and MT-IV are expressed primarily in the brain and NFKB1 stratified squamous epithelium (58), respectively. MT-I and MT-II have been implicated in the scavenging of toxic metals, such as cadmium and mercury, as well as in maintaining homeostasis of biologically essential metals, e.g., zinc and copper (42, 43). Recent studies, however, suggest a significant role for MT-I and MT-II in the maintenance of redox balance (51), controlling the activity of zinc-containing enzymes (37, 52), modulating mitochondrial respiration (67), and scavenging free radicals (64). Studies have exhibited a protective role of MT-I and MT-II against brokers that generate free radicals, e.g., NO, UV radiation, and cadmium (45, 46). Recent investigations with transgenic mice overexpressing MT selectively in the heart have shown that MT can safeguard cardiac tissues from injuries caused by the potent anticancer drug doxorubicin (39, (24R)-MC 976 40). In general, cells refractory to heavy metals and reactive oxygen species appear to tolerate these insults by producing relatively high levels of MT. The genetic evidence that MT is usually a free radical scavenger was exhibited in the yeast in which Cu-Zn superoxide dismutase (SOD) mutant cells are very sensitive to free-radical generators, (e.g., H2O2 and paraquat), and mammalian or yeast MT could replace the function of SOD in these cells (63). Similarly, we have recently shown that this MT level is usually significantly elevated in the livers of Cu-Zn SOD-null mice (24). Most.
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