APOBEC3 proteins can inhibit human immunodeficiency virus type 1 (HIV-1) replication by inducing G-to-A mutations in newly synthesized viral DNA. However, HIV-1 is able to overcome the antiretroviral activity of some of those enzymes by the viral protein Vif. We investigated the impact of different processivities of HIV-1 reverse transcriptases (RT) on the frequencies of G-to-A mutations introd...

Human APOBEC3G inhibits the replication of Vif-deficient HIV-1 by hypermutating nascent viral cDNA (reviewed in [1– 3]). Zheng and colleagues recently reported that the HIV-1 restriction activity of APOBEC3G requires a cellular co-factor [4]. Their conclusion depended on three critical observations: i) CEM-T4 cells support the replication of Vif-deficient HIV-1, ii) CEM-T4 cells express restric...

Introduction Dynamic contrast enhanced MRI (DCE-MRI) holds potential for characterizing key physiological markers of tumor vascularity such as blood brain barrier permeability, which is believed to predict response to therapy and correlate with overall survival time [1]. Robust quantification of permeability is contingent on reliable characterization of contrast agent concentration in feeding v...

APOBEC3 proteins inhibit HIV-1 replication in experimental systems and induce hypermutation in infected patients; however, the relative contributions of several APOBEC3 proteins to restriction of HIV-1 replication in the absence of the viral Vif protein in human primary CD4(+) T cells and macrophages are unknown. We observed significant inhibition of HIV-1Δvif produced in 293T cells in the pres...