Phosphorylation of human erythrocyte band 3 by endogenous p72syk.
The anion transporter, band 3, is the major tyrosine kinase substrate in both red cell membranes and intact human erythrocytes. Using antibodies to various protein-tyrosine kinases, we found that p72syk and p56/53lyn are present in human red cells, while p56lck, pp60src, p59fyn, and p55blk are absent. Treatment of intact red cells with a combination of vanadate and hydrogen peroxide dramatically increased the tyrosine phosphorylation of band 3. This treatment increased the tyrosine kinase activity of p72syk and decreased the activity of p56/53lyn in immune complex kinase assays. Band 3 was found to be associated in immune complexes with p72syk but not with p56/53lyn. These findings suggest that p72syk is responsible, at least in part, for the tyrosine phosphorylation of band 3 in human erythrocytes.
Harrison
M L
ML
Department of Medicinal Chemistry and Pharmacognosy, Purdue University, West Lafayette, Indiana 47907.
Isaacson
C C
CC
Burg
D L
DL
Geahlen
R L
RL
Low
P S
PS
D001457:Anion Exchange Protein 1, Erythrocyte / Q000378:metabolism*; D004792:Enzyme Precursors / Q000097:blood*; D004910:Erythrocyte Membrane / Q000378:metabolism*; D004912:Erythrocytes / Q000201:enzymology; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D010449:Peptide Mapping; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000097:blood*; D000072377:Syk Kinase; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism; D019061:src-Family Kinases
D001457:Anion Exchange Protein 1, Erythrocyte; D004792:Enzyme Precursors; D047908:Intracellular Signaling Peptides and Proteins; D019000:Phosphotyrosine; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases; C000606896:SYK protein, human; D000072377:Syk Kinase; C060902:lyn protein-tyrosine kinase; D019061:src-Family Kinases