Fusion-mediated implantation of band 3 into living cells. A new system to study degradation of membrane proteins.
Sendai virus (SV) glycoproteins were co-reconstituted with the erythrocyte membrane polypeptide designated as band 3 (B3). Fusion of the hybrid vesicles, SV-B3, with L, HeLa and Friend erythroleukemic (FEL) cells led to fusion-mediated implantation of the erythrocyte band 3 into the plasma membranes of the above cells. By the use of radiolabelled band 3 [( 3H]H2DIDS-B3) it was possible to demonstrate that about 1-4 X 10(6) molecules of band 3 can be transferred to the membranes of each of the above cell lines. Cultivation of the recipient cells in growth medium resulted in gradual decrease of the cell-associated counts. The reduction pattern followed first-order kinetics, reaching t 1/2 of disappearance at about 25-30 h in the case of L and HeLa cells, and 57 h in the case of FEL cells. NH4Cl added to the growth medium significantly inhibited the disappearance of band 3 during growth. The studies of the present work indicate that the reduction in the cell-associated band 3 during growth may represent degradation of this polypeptide by the recipient cells.
D000643:Ammonium Chloride / Q000494:pharmacology; D000818:Animals; D001457:Anion Exchange Protein 1, Erythrocyte / Q000378:metabolism*; D001769:Blood; D002455:Cell Division; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007700:Kinetics; D007739:L Cells; D008561:Membrane Fusion; D051379:Mice; D010222:Parainfluenza Virus 1, Human / Q000502:physiology
D001457:Anion Exchange Protein 1, Erythrocyte; D000643:Ammonium Chloride