title: A study of membrane protein defects and alpha hemoglobin chains of red blood cells in human beta thalassemia.
abstract: The soluble pool of alpha hemoglobin chains present in blood or bone marrow cells was measured with a new affinity method using a specific probe, beta A hemoglobin chain labeled with [3H]N-ethylmaleimide. This pool of soluble alpha chains was 0.067 +/- 0.017% of hemoglobin in blood of normal adult, 0.11 +/- 0.03% in heterozygous beta thalassemia and ranged from 0.26 to 1.30% in homozygous beta thalassemia intermedia. This elevated pool of soluble alpha chains observed in human beta thalassemia intermedia decreased 33-fold from a value of 10% of total hemoglobin in bone marrow cells to 0.3% in the most dense red blood cells. The amount of insoluble alpha chains was measured by using the polyacrylamide gel electrophoresis in urea and Triton X-100. In beta thalassemia intermedia the amount of insoluble alpha chains was correlated with the decreased spectrin content of red cell membrane and was associated with a decrease in ankyrin and with other abnormalities of the electrophoretic pattern of membrane proteins. The loss and topology of the reactive thiol groups of membrane proteins was determined by using [3H]N-ethylmaleimide added to membrane ghosts prior to urea and Triton X-100 electrophoresis. Spectrin and ankyrin were the major proteins with the most important decrease of thiol groups.
authors: Institut National de la Santé et de la Recherche Médicale, U 91 Hôpital Henri Mondor, Créteil, France.
authors: P
authors: P
authors: Rouyer-Fessard
authors: M C
authors: MC
authors: Garel
authors: C
authors: C
authors: Domenget
authors: D
authors: D
authors: Guetarni
authors: D
authors: D
authors: Bachir
authors: P
authors: P
authors: Colonna
authors: Y
authors: Y
authors: Beuzard
mesh_terms: D004910:Erythrocyte Membrane / Q000032:analysis*; D005033:Ethylmaleimide / Q000097:blood; D006580:Genetic Carrier Screening; D006441:Hemoglobin A / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D046911:Macromolecular Substances; D008565:Membrane Proteins / Q000097:blood* / Q000235:genetics; D011485:Protein Binding; D012016:Reference Values; D013789:Thalassemia / Q000097:blood* / Q000235:genetics; D014316:Tritium
chemical_list: D046911:Macromolecular Substances; D008565:Membrane Proteins; D014316:Tritium; D006441:Hemoglobin A; D005033:Ethylmaleimide