Figure 1
From: Phosphorylation of HIV Tat by PKR increases interaction with TAR RNA and enhances transcription
Phosphorylation of HIV-1 Tat86 by PKR. (a) PKR was immunoprecipitated from HeLa cell extracts and activated with synthetic dsRNA in the presence of γ-32P-ATP. This activated 32P-PKR was used to phosphorylate 0.5, 1 and 5 μg of synthetic Tat86 in the presence of γ-32P-ATP, at 30°C for 15 minutes. Proteins were separated by 15% SDS-PAGE. (b) PKR immunoprecipitated from HeLa cell extracts, and activated with dsRNA and ATP, was used to phosphorylate 2 μg of synthetic Tat86 at 30°C for the times indicated.