Figure 3. SAMHD1 acetylation upregulates its dNTPase activity.
(A and B) Recombinant GST-SAMHD1 proteins were acetylated in vitro with ±His-ARD1 and blotted with anti-Lys-Ac antibody (lower right). Products were subjected to dGTP-triphosphohydrolase assay and imaged using a phosphorimager (left). The released amount of α-[32P]PP were measured and presented as mean ±S.D. (n=3) (upper right). (C and D) FLAG-mock, SAMHD1 wildtype or K405R mutants were overexpressed with ±MYC-ARD1, then FLAG-tagged proteins were immunoprecipitated from HEK293T (lower right). Precipitated proteins were subjected to dGTP-triphosphohydrolase assay (left) and were quantified (upper right). Shown are mean ±S.D. (n=3). *P<0.05; **P<0.01; t test, N.S.; not significant.