Human Erythrocyte Glycophorin Research Articles

Red cell membrane glycoprotein: Amino acid sequence of an intramembranous region

Human erythrocyte glycophorin has been purified and partially sequenced. The portion of the sequence reported here (51 residues) represents a unique region of glycophorin that, on the basis of labeling experiments reported elsewhere, is probably associated with the hydrophobic interior of the red cell membrane. This sequence has the anticipated hydrophobic characteristics for interaction with the hydrocarbon interior of a membrane and, as far as we are aware, represents the first reported sequence from a hydrophobic region of an integral membrane protein. There is a distribution of charged and hydrophobic residues topographically similar to a cross-section of a phospholipid bilayer, a structure many now accept as the basic feature of a biological membrane. We propose that the hydrophobic sequence of approximately 23 residues comprises the intramembranous domain of human erythrocyte glycophorin and is intimately and possibly specifically associated with lipids of the membrane.