Phosphorylation of STAT-1 serine 727 is only partially dependent on PKR activity.

<p>U937 transfectants were PMA-maturated, infected with <i>S. enteritidis</i>, and treated with a PKR inhibitor (PKR+) or an inhibitor control (PKR−). Cells were harvested 2 hours (A and B) or 5 hours (C and D) after excess bacteria were washed away. The Phosphorylation of STAT-1 serine 727 was studied by Western blot method with p-STAT-1 Ser727 antibody. Cell extracts (35 µg of each) were loaded on SDS-page gel. <b>A</b>, The representative figure at 2 hour time point of U937 cells transfected with genomic clone B27g, vector (mock), misfolding B27H9F or with non-misfolding B27E45 mutants. “C” denotes control <i>S. enteritidis</i>-infected cells without PKR-treatment. <b>B</b>, The relative intensity of STAT-1 serine 727 phosphorylation after PKR inhibition at 2 hour time point. The bars show the mean ± SD of 3 independent experiments. <b>C</b>, The representative figure at 5 hour time point of U937 cells transfected with genomic clone B27g, vector (mock), B27H9F or with B27E45 mutants. <b>D</b>, The relative intensity of STAT-1 serine 727 phosphorylation after PKR inhibition at 5 hour time point. The bars show the mean ± SD of 4 independent experiments. The blots were stripped and reprobed with STAT-1 antibody and Hsc70 antibody as a loading control. The relative Intensity values were normalized to the <i>S. enteritidis</i>-infected control (C, which is given value one). * = <i>P</i><0.05 versus 2 h/5 h of the respective cell line.