The purpose of figure 3A was to

A  Show that treatment of RBC and K562 cells overexpressing ABCB6 with PNGase F proved ABCB6 is expressed as a N-glycosylated protein.

B  Provide evidence that overexpression of HA-tagged ABCB6 in K562 cells was not identified using the ABCB6 antibodies and test four different ABCB6 antibodies; some of which were commerically made and others custom made.

C  Test four different ABCB6 antibodies; some of which were commerically made and others custom made and show that porin was not located in the membranes of red blood cell ghosts.

D  Provide evidence that overexpression of HA-tagged ABCB6 in K562 cells was not identified using the ABCB6 antibodies and show that porin was not located in the membranes of red blood cell ghosts.