tailieunhanh - Báo cáo y học: " The cellular source for APOBEC3G’s incorporation into HIV"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: The cellular source for APOBEC3G’s incorporation into HIV-1. | Ma et al. Retrovirology 2011 8 2 http content 8 1 2 RETR0VIR0L0GY RESEARCH Open Access The cellular source for APOBEC3G s incorporation into HIV-1 134 1 1 71 1 1 1 1 I- z 2 Jing Ma Xiaoyu Li Jian Xu Quan Zhang Zhenlong Liu Pingping Jia Jinming Zhou Fei Guo Xuefu You1 Liyan Yu1 Lixun Zhao1 Jiandong Jiang1 Shan Cen1 3 4 Abstract Background Human APOBEC3G hA3G has been identified as a cellular inhibitor of HIV-1 infectivity. Viral incorporation of hA3G is an essential step for its antiviral activity. Although the mechanism underlying hA3G virion encapsidation has been investigated extensively the cellular source of viral hA3G remains unclear. Results Previous studies have shown that hA3G forms low-molecular-mass LMM and high-molecular-mass HMM complexes. Our work herein provides evidence that the majority of newly-synthesized hA3G interacts with membrane lipid raft domains to form Lipid raft-associated hA3G RA hA3G which serve as the precursor of the mature HMM hA3G complex while a minority of newly-synthesized hA3G remains in the cytoplasm as a soluble LMM form. The distribution of hA3G among the soluble LMM form the RA LMM form and the mature forms of HMM is regulated by a mechanism involving the N-terminal part of the linker region and the C-terminus of hA3G. Mutagenesis studies reveal a direct correlation between the ability of hA3G to form the RA LMM complex and its viral incorporation. Conclusions Together these data suggest that the Lipid raft-associated LMM A3G complex functions as the cellular source of viral hA3G. Background Human APOBEC3G hA3G has been identified as one of anti-HIV-1 host factors 1 . hA3G belongs to an APOBEC superfamily containing at least 11 members which share a cytidine deaminase motif a conserved His-X-Glu and Cys-X-X-Cys zinc coordination motif 2 . The APOBEC superfamily in humans includes APO-BEc1 APOBEC2 aPoBEC3A-H hA3A-H APOBEC4 and activation-induced cytidine deaminase AID . The virus counters hA3G s .