Restricting HIV the SAMHD1 way: through nucleotide starvation.

Institut Pasteur, Unité Virus et Immunité, Département de Virologie, Centre National de la Recherche Scientifique, Unité de Recherche Associée 3015, 28 rue du Docteur Roux, F-75015 Paris, France.
Nature Reviews Microbiology (Impact Factor: 23.32). 08/2012; 10(10):675-80. DOI: 10.1038/nrmicro2862
Source: PubMed

ABSTRACT HIV replication is limited by cellular restriction factors, such as APOBEC and tetherin, which themselves are counteracted by viral proteins. SAMHD1 was recently identified as a novel HIV restriction factor in myeloid cells, and was shown to be blocked by the lentiviral protein Vpx. SAMHD1 limits viral replication through an original mechanism: it hydrolyses intracellular dNTPs in non-cycling cells, thus decreasing the amount of these key substrates, which are required for viral DNA synthesis. In this Progress article, we describe how SAMHD1 regulates the pool of intracellular nucleotides to control HIV replication and the innate immune response.

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