Fig. 1. Co-expression of BRII and BRIa leads to rearrangement of BRIa on the cell surface. Stimulation of cells expressing BRII and BRIa with BMP-2 causes an aggregation of the receptors. BRIa-ca, which is constitutively active, needs the co-expression of BRII for redistribution. COS-7 cells were transiently transfected with myc-tagged BRII and HA-tagged versions of BRIa or BRIa-ca. After 48 hours, cells stimulated with BMP-2 or nonstimulated cells were fixed and the receptors labelled with fluorescent antibodies against the epitope tags. Cell membrane expression of the receptors was visualised by confocal microscopy. Forty images were collected at the highest magnification (Zoom10). From these images the CD value of the BMP receptors was calculated using ICS. (A) COS7 cells were mock transfected, fixed and incubated with the fluorescent HA-antibody. The mock-transfected cells showed no significant fluorescence. (B) COS7 cells were mock transfected, fixed and incubated with the biotin conjugated myc antibody followed by the secondary anti-biotin RRX antibody. The mock-transfected cells show no significant fluorescence. (C) COS7 cells were transfected with a plasmid encoding HA-BRIa, fixed and fluorescently labelled using the FITC conjugated HA-antibody. (D) COS7 cells were transfected with a plasmid encoding myc-BRII. Cells were fixed and fluorescently labelled using the biotin-conjugated myc-antibody followed by a RRX conjugated anti-biotin antibody. (E) Calculated average CD values for BRIa or BRIa-ca. Transfected COS7 cells were fluorescently labelled with a fluorescent antibody against the HA-epitope. Confocal images were taken and the CD values for BRIa and BRIa-ca were calculated by applying ICS. (F) Calculated average CD values for myc-BRIa. After transfection cells were fixed and labelled using a biotin-conjugated antibody against the myc-epitope followed by a fluorescent secondary antibody. Confocal images were taken and the CD values for myc-BRIa were calculated by applying ICS. (G) Calculated average CD values for myc-BRII. Transfected COS7 cells were fluorescently labelled with a biotin-conjugated antibody against the myc-epitope followed by a fluorescent anti-biotin antibody. Confocal images were taken and the CD values for BRII were calculated by applying ICS.

Return to article