Band 3 Erythrocyte Membrane Protein Acts as Redox Stress Sensor Leading to Its Phosphorylation by p⁷² Syk

Figure 5

Band 3 modifications, hemichrome formation, and hemolysis after phenylhydrazine treatment. Erythrocytes were treated with 1 mM phenylhydrazine (PHZ) at different incubation times in the presence or in the absence of Syk inhibitor II (Syk I.). Band 3 tyrosine phosphorylation (panel (a)), oxidized band 3 (panel (b)), Syk phosphorylation (panel (c)), and Syk translocation (panel (d)) were quantified acquiring anti-phosphotyrosine, anti-band 3, and anti-Syk western blots using an IR fluorescence detection scanner (Odyssey, Licor, USA) and analyzing images with Odyssey V3.0 software. Values are the average of 5 separated experiments and are expressed as arbitrary units (au); the bars represent the standard deviations. Hemichromes (HMC) were quantified by vis spectrometry (panel (e)), hemolysisby measuring hemoglobin absorbance at 405 nm (panel (f)) and are expressed in nmoles/mL. indicates the minimal concentration or shorter incubation time that determines a statistically significant change by Student’s -test in comparison to the control sample ().

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