HIV-1 Nef co-localizes with the astrocyte-specific cytoskeleton protein GFAP in persistently nef-expressing human astrocytes

In T-cells HIV-1 Nef exerts various functions and interacts with actin. In astrocytes interaction of Nef xvith cellular proteins is poorly understood. Therefore, human astrocytic cell clones stably transfected with nef-genes derived from HIV-1 Bru and its myristoylation-defective TH-variant were inv estigated by confocal laser scanning microscopy for expression of Nef and c ytoskeleton proteins actin and GFAP, a marker for activated astrocytes. Myr istoylated Nef was detected in cytoplasm, Golgi and plasmamembrane, while n on-myristoylated Nef was exclusively cytoplasmic. Nef co-localised with GFA P in the perinuclear region of astrocytes. In contrast, Nef did not interac t with actin filaments in human astrocytes. Nef/GFAP interaction could cont ribute to changes in morphology and activation state of astrocytes shown pr eviously which are both critical for development of astrogliosis in HIV-1 i nfected brain.