2. Right - for instance: the secondary antibody is past its expiration date - rodamine is no longer conjugated to the antibody and it binds in a non specific manner to the plasma membrane because it is a hydrophobic moeity.
3. Right - this is the cell line you should select as your overexpression system.
4. Wrong - since the antibody can react only with protein present on the extracellular face of the cell membrane, when a high signal is detected we know that the protein is located in the cell membrane.
5. Right - you can see that the overall expression of BHR1 in these cells is lower in the western blot as well.
6. Wrong - look at the western blot - these cells express high amounts of the protein, but the protein is not located in the plasma membrane.
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