Methods to Visualize MAVS Subcellular Localization
The mitochondrial antiviral signaling (MAVS) protein is a central adaptor protein required for antiviral innate immune signaling. To facilitate its roles in innate immunity, MAVS localizes to multiple intracellular membranous compartments, including the mitochondria, the mitochondrial-associated ER membrane (MAM), and peroxisomes. Studies of MAVS function therefore often require an analysis of MAVS localization. To detect MAVS protein on intracellular membranes, biochemical fractionation to isolate MAMs, mitochondria, or peroxisomes can be used. Further, immunofluorescence with antibodies against specific membrane markers can be used to visualize MAVS distribution throughout the cell. Here, we describe the biochemical fractionation and immunofluorescence protocols used to detect MAVS subcellular localization.
Key wordsMAVS Mitochondria MAM Peroxisomes Endoplasmic reticulum Fractionation Immunofluorescence Interferon
We thank the Duke University Light Microscopy Core Facility for assistance with imaging and analysis. Research in the Horner laboratory is supported by funds from the National Institutes of Health (NIH) (R01AI125416 and R21AI124100) and a Duke School of Medicine Whitehead Scholarship. Additional funding sources include the Ford Foundation (CV) and NIH T32CA009111 (DCB).
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