Selective 14-3-3γ induction quenches p-ß-catenin Ser37/Bax-enhanced cell death in cerebral cortical neurons during ischemia.

Ischemia-induced cell death is a major cause of disability or death after stroke. Identifying the key intrinsic protective mechanisms induced by ischemia is critical for the development of effective stroke treatment. Here, we reported that 14-3-3γ was a selective ischemia-inducible survival factor in cerebral cortical neurons reducing cell death by downregulating Bax depend direct 14-3-3γ/p-ß-catenin Ser37 interactions in the nucleus. 14-3-3γ, but not other 14-3-3 isoforms, was upregulated in primary cerebral cortical neurons upon oxygen-glucose deprivation (OGD) as measured by quantitative PCR, western blot and fluorescent immunostaining. The selective induction of 14-3-3γ in cortical neurons by OGD was verified by the in vivo ischemic stroke model. Knocking down 14-3-3γ alone or inhibiting 14-3-3/client interactions was sufficient to induce cell death in normal cultured neurons and exacerbate OGD-induced neuronal death. Ectopic overexpression of 14-3-3γ significantly reduced OGD-induced cell death in cultured neurons. Co-immunoprecipitation and fluorescence resonance energy transfer demonstrated that endogenous 14-3-3γ bound directly to more p-ß-catenin Ser37 but not p-Bad, p-Ask-1, p-p53 and Bax. During OGD, p-ß-catenin Ser37 but not p-ß-catenin Ser45 was increased prominently, which correlated with Bax elevation in cortical neurons. OGD promoted the entry of 14-3-3γ into the nuclei, in correlation with the increase of nuclear p-ß-catenin Ser37 in neurons. Overexpression of 14-3-3γ significantly reduced Bax expression, whereas knockdown of 14-3-3γ increased Bax in cortical neurons. Abolishing ß-catenin phosphorylation at Ser37 (S37A) significantly reduced Bax and cell death in neurons upon OGD. Finally, 14-3-3γ overexpression completely suppressed ß-catenin-enhanced Bax and cell death in neurons upon OGD. Based on these data, we propose that the 14-3-3γ/p-ß-catenin Ser37/Bax axis determines cell survival or death of neurons during ischemia, providing novel therapeutic targets for ischemic stroke as well as other related neurological diseases.

Detection of animal viruses using nucleic acid sequence-based amplification (NASBA).

As seen in recent avian influenza outbreaks in Asia, prevention is the key to fighting infectious disease successfully. Efficient disease surveillance systems on the basis of molecular diagnostics will help monitor the emergence of viruses in the early stage and thus prompt containment measures can be in place to minimize disease spread. Here we describe and review molecular diagnostics focusing on nucleic acid sequence-based amplification (NASBA) technology in detecting viruses causing animal diseases, such as avian influenza, foot-and-mouth disease, and Newcastle disease. NASBA offers high sensitivity, specificity, accuracy, and speed of availability of results, and NASBA would be the most applicable molecular diagnostics for disease surveillance and control.