Metabolic depletion effect on serine/threonine- and tyrosine-phosphorylations of membrane proteins in human erythrocytes.
The response of serine/threonine-phosphorylation of the major transmembrane protein (band 3) in human erythrocytes to the metabolic state of the cells is different from that exhibited by the tyrosine-phosphorylation of the same protein. Precisely, both serine- and tyrosine-phosphorylation are decreased during metabolic depletion of the erythrocytes. However, the depletion-induced tyrosine-phosphorylation decrease of band 3 is not reversed by the subsequent metabolic repletion of the depleted cells, being accompanied by an irreversible inactivation of both membrane-bound and cytosolic tyrosine-protein kinase(s). By contrast, the depletion-induced phosphoserine-dephosphorylation is reversed by the following repletion, being accompanied by a reversible translocation of casein kinase(s) between cytosolic and membrane compartments. A possible functional correlation between the serine-phosphorylation state of band 3 protein and the band 3-mediated anion transport across the membrane is discussed.
Clari
G
G
Dipartimento Chimica Biologica, Università di Padova, Italy.
Marzaro
G
G
Moret
V
V
D001345:Autoradiography; D001692:Biological Transport; D047388:Casein Kinases; D002463:Cell Membrane Permeability; D003600:Cytosol / Q000201:enzymology / Q000378:metabolism; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D012694:Serine / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*
D008565:Membrane Proteins; D013912:Threonine; D014443:Tyrosine; D012694:Serine; D011494:Protein Kinases; D011505:Protein-Tyrosine Kinases; D047388:Casein Kinases