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Functional organization of human SAMHD1 and mechanisms of HIV-1 restriction.

ABSTRACT: Sterile alpha motif and histidine-aspartate domain containing protein 1 (SAMHD1) is a triphosphohydrolase that catalyzes the conversion of deoxyribonucleoside triphosphate to deoxyribonucleoside and triphosphate. SAMHD1 has been a recent focus of study since it was identified as a potent human immunodeficiency virus-1 (HIV-1) restriction factor in the intrinsic antiviral immune system. Recent biochemical and biological studies have suggested that SAMHD1 restricts HIV-1 infection in non-cycling cells by limiting the pool of deoxyribonucleoside triphosphates, thereby interfering with HIV-1 reverse transcription. SAMHD1 also possesses single-stranded DNA and RNA binding activity, with reported nuclease activity, conferring additional HIV-1 restriction function. This review summarizes current knowledge regarding the structure of SAMHD1 and the regulation of its function in HIV-1 restriction.

SUBMITTER: Ahn J

PROVIDER: S-EPMC4939630 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Functional organization of human SAMHD1 and mechanisms of HIV-1 restriction.

Ahn Jinwoo J

Biological chemistry 20160401 4

Sterile alpha motif and histidine-aspartate domain containing protein 1 (SAMHD1) is a triphosphohydrolase that catalyzes the conversion of deoxyribonucleoside triphosphate to deoxyribonucleoside and triphosphate. SAMHD1 has been a recent focus of study since it was identified as a potent human immunodeficiency virus-1 (HIV-1) restriction factor in the intrinsic antiviral immune system. Recent biochemical and biological studies have suggested that SAMHD1 restricts HIV-1 infection in non-cycling c ...[more]

PMID: 26733158

Similar Datasets

The ribonuclease activity of SAMHD1 is required for HIV-1 restriction.

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| S-EPMC4318684 | biostudies-literature

The ribonuclease activity of SAMHD1 is required for HIV-1 restriction

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2014-06-13 | GSE58418 | GEO

Nuclease activity of the human SAMHD1 protein implicated in the Aicardi-Goutieres syndrome and HIV-1 restriction.

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SAMHD1-mediated HIV-1 restriction in cells does not involve ribonuclease activity.

Project description: Not available

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HIV-2 Vpx neutralizes host restriction factor SAMHD1 to promote viral pathogenesis.

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SAMHD1 is the dendritic- and myeloid-cell-specific HIV-1 restriction factor counteracted by Vpx.

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