日前，在《自然》杂志网站上的报告称，英国研究人员探明了人体内一种蛋白质对抗艾滋病病毒的原理，并有望在此基础上开发出新的艾滋病治疗方法。
此前美、法等国的研究人员曾发现，人体内一种名为SAMHD1的蛋白质能阻止艾滋病病毒在一些白细胞中的复制，但对其中的原理并不清楚。
英国曼彻斯特大学等机构的研究人员发现，这种蛋白质能降解脱氧核苷酸，而脱氧核苷酸正是艾滋病病毒复制所需要的基础。
领导研究的米歇尔·韦布说，艾滋病病毒的复制在艾滋病感染进程中是关键的一步，如能阻止病毒复制，就可有效遏制艾滋病的感染进程。研究人员未来可通过模拟相关生理过程，开发出新的艾滋病治疗方法或艾滋病疫苗。（生物谷 Bioon.com)
doi:10.1038/nature10623
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HIV-1 restriction factor SAMHD1 is a deoxynucleoside triphosphate triphosphohydrolase
David C. Goldstone, Valerie Ennis-Adeniran, Joseph J. Hedden, Harriet C. T. Groom, Gillian I. Rice, Evangelos Christodoulou, Philip A. Walker, Geoff Kelly, Lesley F. Haire, Melvyn W. Yap, Luiz Pedro S. de Carvalho, Jonathan P. Stoye, Yanick J. Crow, Ian A. Taylor & Michelle Webb
SAMHD1, an analogue of the murine interferon (IFN)-γ-induced gene Mg11 (ref. 1), has recently been identified as a human immunodeficiency virus-1 (HIV-1) restriction factor that blocks early-stage virus replication in dendritic and other myeloid cells2, 3 and is the target of the lentiviral protein Vpx, which can relieve HIV-1 restriction4, 5, 6, 7. SAMHD1 is also associated with Aicardi–Goutières syndrome (AGS), an inflammatory encephalopathy characterized by chronic cerebrospinal fluid lymphocytosis and elevated levels of the antiviral cytokine IFN-α8. The pathology associated with AGS resembles congenital viral infection, such as transplacentally acquired HIV. Here we show that human SAMHD1 is a potent dGTP-stimulated triphosphohydrolase that converts deoxynucleoside triphosphates to the constituent deoxynucleoside and inorganic triphosphate. The crystal structure of the catalytic core of SAMHD1 reveals that the protein is dimeric and indicates a molecular basis for dGTP stimulation of catalytic activity against dNTPs. We propose that SAMHD1, which is highly expressed in dendritic cells, restricts HIV-1 replication by hydrolysing the majority of cellular dNTPs, thus inhibiting reverse transcription and viral complementary DNA (cDNA) synthesis.
