SAMHD1 and HIV-1 infection: Thus, in contrast to other antiretroviral host restriction factors, such as TRIM-5alpha, ABOPEC3G proteins, and tetherin [7-9], SAMHD1 does not directly target viral components to suppress viral replication but seems to restrict HIV-1 infection of non-dividing cells by decreasing the dNTP pool concentration below the threshold required for effective reverse transcription [10,11].