Shape control in the human red cell.
When the human red cell consumes its ATP, the cell loses its discoid character in favour of a spiculated and eventually a spherical form. This discocyte-echinocyte transformation parallels both degradation of phosphatidylinositol 4,5-bisphosphate and phosphatidic acid but not dephosphorylation of cytoskeletal proteins. Dephosphorylation of both spectrin and band 3 lags behind metabolic crenation. Exogenous vanadate accelerates both shape changes and lipid dephosphorylation in a parallel manner during metabolic depletion. In contrast to its effect on lipids, vanadate reduces the rate of protein dephosphorylation. These observations strongly support a shape control mechanism in the red cell, based on phosphoinositide metabolism and compatible with a bilayer-couple model.
D000255:Adenosine Triphosphate / Q000378:metabolism; D002118:Calcium / Q000494:pharmacology; D004912:Erythrocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D010712:Phosphatidic Acids / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate; D010716:Phosphatidylinositols / Q000378:metabolism; D010766:Phosphorylation; D014638:Vanadates; D014639:Vanadium / Q000494:pharmacology
D010712:Phosphatidic Acids; D019269:Phosphatidylinositol 4,5-Diphosphate; D010716:Phosphatidylinositols; D014639:Vanadium; D014638:Vanadates; D000255:Adenosine Triphosphate; D002118:Calcium