Figure 6

The HSP83 3'-UTR is essential for enhanced translation during heat shock. L. infantum promastigotes transfected with constructs pXCATIRs (A), pXIRPstCATIR (B), pX5HisCATIR (C), or pX5HisCAT3His (D) were metabolically labeled for 2 h at 26°C (lanes 1), 37°C (lanes 2), 39°C (lanes 3), or 41°C (lanes 4) in the presence of [³⁵S]methionine/cysteine. Proteins (4 × 10⁶ cells per lane) were separated by SDS-PAGE and the corresponding autoradiographies are shown (panels a). In parallel, cells were harvested and lysed, and the CAT protein was immunoprecipited using a specific antibody. Panel b shows the immunoprecipitation followed by autoradiography. Panel c shows the immunoprecipitation followed by Western blot using an anti-CAT antibody. The label intensity of the immunoprecipitated CAT protein (panels b) was measured by densitometric scanning and normalized relative to the total amount of immunoprecipitated CAT protein as determined by Western blot (panels c). The relative signals are shown in panels d. Data represent mean values derived from at least two independent experiments.