Immobilized pH gradient two-dimensional gel electrophoresis and mass spectrometric identification of cytokine-regulated proteins in ME-180 cervical carcinoma cells.

Two-dimensional (2-D) polyacrylamide gel electrophoresis combined with mass spectrometry is a powerful combination of technologies that allows high resolution separation of proteins and their rapid identification. Immobilized pH gradient (IPG) first-dimensional gels have several advantages over carrier ampholyte isoelectric focusing, including a high degree of reproducibility, good protein spot resolution, and a selection of pH range. Here we demonstrate the utility and efficacy of combining IPG 2-D gel electrophoresis with mass spectrometry to identify interferon-gamma- (IFN) and tumor necrosis factor (TNF)-regulated proteins in ME-180 cervical carcinoma cells.

Functional expression of falcipain, a Plasmodium falciparum cysteine proteinase, supports its role as a malarial hemoglobinase.

Erythrocytic malaria parasites degrade hemoglobin as a principal source of amino acids for parasite protein synthesis. We have previously shown that a Plasmodium falciparum trophozoite cysteine proteinase, now termed falcipain, is required for hemoglobin degradation, and we have hypothesized that this proteinase is responsible for initial cleavages of hemoglobin. To further evaluate the biological role of falcipain, we expressed the enzyme in bacterial and viral expression systems.