ARMS-NF-κB signaling regulates intracellular ROS to induce autophagy-associated cell death upon oxidative stress

Abstract

Summary: Ankyrin repeat-rich membrane spanning (ARMS) plays roles in neural development, neuropathies, and tumor formation. Such pleiotropic function of ARMS is often attributed to diverse ARMS-interacting molecules in different cell context. However, it might be achieved by ARMS’ effect on global biological mediator like reactive oxygen species (ROS). We established ARMS-knockdown in melanoma cells (siARMS) and in Drosophila eyes (GMR>dARMSRNAi) and challenged them with H2O2. Decreased ARMS in both systems compromises nuclear translocation of NF-κB and induces ROS, which in turn augments autophagy flux and confers susceptibility to H2O2-triggered autophagic cell death. Resuming NF-κB activity or reducing ROS by antioxidants in siARMS cells and GMR>dARMSRNAi fly decreases intracellular peroxides level concurrent with reduced autophagy and attenuated cell death. Conversely, blocking NF-κB activity in wild-type flies/melanoma enhances ROS and induces autophagy with cell death. We thus uncover intracellular ROS modulated by ARMS-NFκB signaling primes autophagy for autophagic cell death upon oxidative stress.

Keywords

• Biological sciences
• Molecular biology
• Cell biology