Figure 2.

Expression patterns of SAMHD1 during HCMV infection in HF cells. (A) Non-synchronized sub-confluent HF cells in six-well plates were mock-infected (M) or infected with intact HCMV (Towne) or UV-inactivated virus (UV-HCMV) at an MOI of 1. Total cell lysates were prepared at the indicated time points, subjected to SDS-8% PAGE, and immunoblotted with antibodies for SAMHD1, IE1/IE2, and β-actin. SAMHD1 bands are indicated with an arrowhead and non-specific bands are indicated as an open circle. (B) HF cells were infected as in (A). Total mRNAs were prepared at the indicated time points, and the levels of SAMHD1 and β-actin transcripts were measured by qRT-PCR. The relative SAMHD1 mRNA level is normalized with the level of β-actin. Results shown are mean values and standard errors of three independent experiments. Values of *P < 0.05 and **P < 0.01 are indicated. (C) HF cells in six-well plates were mock-infected or infected with HCMV (Towne) at an MOI of 0, 5, or 3, and harvested at the indicated time points. Total cell lysates were prepared and subjected to SDS-8% PAGE, followed by immunoblotting with antibodies for SAMHD1, IE1/IE2, p52 (UL44), pp28 (UL99), and β-actin. (D) HF cells in six-well plates were mock-infected or infected with HCMV (Towne) at an MOI of 1 and harvested at the indicated time points. For inhibitor treatment, cells were treated with DMSO or phosphonoacetic acid (PAA) (200 μg/ml; Sigma-Aldrich) at 24 h post infection. Total cell lysates were prepared and subjected to SDS-8% PAGE, followed by immunoblotting with antibodies for SAMHD1, IE1/IE2, p52 (UL44), pp28 (UL99), and β-actin.