SAMHD1

SAMHD1

A gene on chromosome 20pter-q12 that encodes a putative nuclease involved in the innate immune response, which acts by downregulating cell-intrinsic antiviral response. It may play a role in mediating pro-inflammatory responses to TNF-alpha signalling. It is expressed in the heart, skeletal muscle, spleen, liver and elsewhere, but not in the brain or thymus.

Molecular pathology
Defects in SAMHD1 cause Aicardi-Goutieres syndrome type 5 and chilblain lupus type 2.
References in periodicals archive ?
Scientists realized HIV was only capable of multiplying in macrophages when an antiviral protein called SAMHD1 was temporarily turned off.
We knew that SAMHD1 is switched off when cells multiply, but macrophages do not multiply so it seemed unlikely that SAMHD1 would be switched off in these cells," Gupta wrote.
SAMHD1 es una proteina inducida por el IFN-[alpha].
Contribution of SAM and HD domains to retroviral restriction mediated by human SAMHD1.
SAMHD1 is the dendritic- and myeloid-cell-specific HIV-1 restriction factor counteracted by Vpx.
Since the discovery, scientists have sought to understand how SAMHD1 works to protect these cells, with hopes that science might find a way to synthetically apply that protection to other cells.
Researchers wanted to understand how cells containing the SAMHD1 protein are protected from such hijacking.
Instead, the virus has evolved to replicate mainly in a different kind of cell, called CD4 T-cells, which do not contain SAMHD1 and therefore have a healthy pool of dNTPs.
Scientists in the United States and France recently discovered that a protein named SAMHD1 was able to prevent HIV replicating in a group of white blood cells called myeloid cells.
Now, crucially, the teams from Manchester and the MRC have shown how SAMHD1 prevents the virus from replicating itself within these cells, opening up the possibility of creating drugs that imitate this biological process to prevent HIV replicating in the sentinel cells of the immune system.
The factor, a protein called SAMHD1, is part of the nucleic acid sensing machinery within the body's own immune system.
SAMHD1 factor, researchers have found, can also sense and interfere with infection of myeloid cells, such as macrophages and dendritic cells, with HIV-1 and related immunodeficiency viruses.