Suppressed Fusion: Concurrently, HIV infection often downregulates the key proteins mediating mitochondrial fusion, such as MFN1, MFN2 (Mitofusin 1 and Mitofusin 2, regulating outer membrane fusion), and OPA1,(Optic atrophy 1, regulating inner membrane fusion) (17). This evidence concerns the gene MFN2 and HIV infectious disease.