Band 3 Tokyo: Thr837-->Ala837 substitution in erythrocyte band 3 protein associated with spherocytic hemolysis.
We report a case of spherocytosis associated with erythrocyte band 3 deficiency. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of erythrocyte membrane proteins showed that the patient's band 3 was reduced to about 80% of the control level. Molecular analysis revealed that this quantitative alteration was accompanied by a novel base change at codon 837 (ACG-->GCG) of the AE1 gene, resulting in substitution of alanine for threonine. In bone marrow mononuclear cells, both mutant and wild-type mRNA were comparably detected, suggesting that this mutation interfered with band 3 processing or assembly, leading to impaired accumulation of mutant band 3 in the plasma membrane.
Iwase
S
S
Department of Internal Medicine, Aoto Hospital, Jikei University School of Medicine, Tokyo, Japan. aoto-hsp@fa2.so-net.pr.jp
Ideguchi
H
H
Takao
M
M
Horiguchi-Yamada
J
J
Iwasaki
M
M
Takahara
S
S
Sekikawa
T
T
Mochizuki
S
S
Yamada
H
H
D000328:Adult; D000409:Alanine / Q000235:genetics; D019943:Amino Acid Substitution / Q000235:genetics*; D001457:Anion Exchange Protein 1, Erythrocyte / Q000172:deficiency / Q000235:genetics*; D006801:Humans; D008297:Male; D017354:Point Mutation; D013103:Spherocytosis, Hereditary / Q000097:blood / Q000235:genetics*; D013912:Threonine / Q000235:genetics