title: The contribution of Ca+ calmodulin activation of human erythrocyte AMP deaminase (isoform E) to the erythrocyte metabolic dysregulation of familial phosphofructokinase deficiency.
abstract: Erythrocyte membrane leakage of Ca2+ in familial phosphofructokinase deficiency results in a compensatory increase of Ca2+-ATPase activity that depletes ATP and leads to diminished erythrocyte deformability and a higher rate of hemolysis. Lowered ATP levels in circulating erythrocytes are accompanied by increased IMP, indicating that activated AMP deaminase plays a role in this metabolic dysregulation. Exposure to a calmodulin antagonist significantly slows IMP accumulation during experimental energy imbalance in patients' cells to levels that are similar to those in untreated controls, implying that Ca2+-calmodulin is involved in erythrocyte AMP deaminase activation in familial phosphofructokinase deficiency. Therapies directed against activated isoform E may be beneficial in this compensated anemia.
authors: Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA. sabinar@mcw.edu
authors: Richard L
authors: RL
authors: Sabina
authors: Anders
authors: A
authors: Waldenström
authors: Gunnar
authors: G
authors: Ronquist