Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157.
Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157.
J Biol Chem. 2011 Dec 23;286(51):43596-43600. doi: 10.1074/jbc.C111.317628. Epub 2011 Nov 7.
The SAMHD1 protein is an HIV-1 restriction factor that is targeted by the HIV-2 accessory protein Vpx in myeloid lineage cells. Mutations in the SAMHD1 gene cause Aicardi-Goutières syndrome, a genetic disease that mimics congenital viral infection. To determine the physiological function of the SAMHD1 protein, the SAMHD1 gene was cloned, recombinant protein was produced, and the catalytic activity of the purified enzyme was identified. We show that SAMHD1 contains a dGTP-regulated deoxynucleotide triphosphohydrolase. We propose that Vpx targets SAMHD1 for degradation in a viral strategy to control cellular deoxynucleotide levels for efficient replication.
SAMHD1 蛋白是一种 HIV-1 限制因子,可被 HIV-2 辅助蛋白 Vpx 靶向作用于髓系细胞。SAMHD1 基因突变会导致 Aicardi-Goutières 综合征,这是一种类似于先天性病毒感染的遗传性疾病。为了确定 SAMHD1 蛋白的生理功能,我们克隆了 SAMHD1 基因,制备了重组蛋白,并鉴定了纯化酶的催化活性。结果表明,SAMHD1 包含一个 dGTP 调节的脱氧核苷酸三磷酸水解酶。我们提出 Vpx 靶向 SAMHD1 进行降解,这是一种病毒策略,可控制细胞内脱氧核苷酸水平,以实现高效复制。