Fig. 5

Effect of CBL on insect cells. a CBL-FITC binding to sf21 cells. CBL-FITC (1μg/mL) was added to sf21 cells for 30 mins. The surface binding of CBL-FITC to sf21 cells was determined by mean fluorescence intensity (FL1) using flow cytometry. The sugar used as a competitor in the binding solution of CBL-FITC and sf21 cells was indicated. Purple: cells without CBL-FITC treatment; light blue: N-Acetyl-D-glucosamine pretreated (GlcNAc); red: N-Acetyl-D-galactosamine pretreated (GalNAc); deep blue: CBL-FITC alone (Non); orange: N-Acetyl-β-D-mannosamine pretreated (ManNAc). b CBL reduces the mitochondrial membrane potential in sf21 cells. Sf21 cells were incubated with or without CBL for 24 h. Cells were stained for JC-1 to measure the change in mitochondrial membrane potential and observed under the fluorescence microscope. The reduction in mitochondrial membrane potential corresponds to increase in green fluorescence (free JC-1) and decrease in red fluorescence (aggregates JC-1)