Rabbit Anti-Human AIF Polyclonal Antibody Knockout Validated

BackgroundPorcine Epidemic Diarrhea (PED) is an acute and highly contagious enteric disease caused by PED virus (PEDV), characterized by vomitting, watery diarrhea and fatal dehydration with high mortality in sucking piglets of one week of age. Although PEDV induced cell apoptosis has been established in vitro and in vivo, the functional protein that contributes to this event remains unclear.MethodsThe activation or cleavage of main apoptosis-associated molecular such as AIFM1, caspase-3, caspase-8, caspase-9 and PARP in PEDV infected host cells were analyzed by western blotting. The nuclear change of infected cell was monitored by confocal immunofluorescence assay. The overexpressing plasmids of 16 non-structural proteins (Nsp1-16) and 6 structural proteins (M, N, E, ORF3, S1 and S2) were constructed by cloning. Cell apoptosis induced by PEDV or overexpression non-structural or structural proteins was measured by the flow cytometry assay.ResultsPEDV could infect various host cells including Vero, Vero-E6 and Marc-145 and cause obvious cytopathic effects, including roundup, cell fusion, cell membrane vacuolation, syncytium formation and cause apparent apoptosis. In infected cells, PEDV-induced apoptosis is accompanied by nuclear concentration and fragmentation as a result of caspase-3 and caspase-8 activation and AIFM1 and PARP cleavage. Overexpression of S1 Spike protein of PEDV SM98 strain effectively induced host cell apoptosis, while the expression of the other non-structure proteins (Nsp1-16) and structural proteins (M, N, E, S2 and ORF3) has no or less effect on cell apoptosis. Similarly, expression of S1 protein from wild-type strain BJ2011 or cell-adapted strain CV777, also induce apoptosis in transfected cells. Finally, we demonstrated that the S1 proteins from various coronavirus family members such as TGEV, IBV, CCoV, SARS and MERS could also induce Vero-E6 cells apoptosis.ConclusionS1 Spike protein is one of the most critical functional proteins that contribute to cell apoptosis. Expression of S1 proteins of the coronavirus tested in this study could all induce cell apoptosis suggesting S1 maybe is an effective inducer in Coronavirus-induced cell apoptosis and targeting S1 protein expression probably is a promising strategy to inhibit coronavirus infection and thus mediated apoptosis on host cells.

Inhibition of oxidative phosphorylation (OXPHOS) by 1-cyclopropyl-4-(4-[(5-methyl-3-(3-[4-(trifluoromethoxy) phenyl]-1,2,4-oxadiazol-5-yl)-1H-pyrazol-1-yl) methyl] pyridin-2-yl) piperazine (BAY87-2243, abbreviated as B87), a complex I inhibitor, fails to kill human cancer cells in vitro. Driven by this consideration, we attempted to identify agents that engage in synthetically lethal interactions with B87. Here, we report that dimethyl alpha-ketoglutarate (DMKG), a cell-permeable precursor of alpha-ketoglutarate that lacks toxicity on its own, kills cancer cells when combined with B87 or other inhibitors of OXPHOS. DMKG improved the antineoplastic effect of B87, both in vitro and in vivo. This combination caused MDM2-dependent, tumor suppressor protein p53 (TP53)-independent transcriptional reprogramming and alternative exon usage affecting multiple glycolytic enzymes, completely blocking glycolysis. Simultaneous inhibition of OXPHOS and glycolysis provoked a bioenergetic catastrophe culminating in the activation of a cell death program that involved disruption of the mitochondrial network and activation of PARP1, AIFM1, and APEX1. These results unveil a metabolic liability of human cancer cells that may be harnessed for the development of therapeutic regimens.