Hereditary elliptocytosis due to both qualitative and quantitative defects in membrane skeletal protein 4.1

Blood ◽  
1991 ◽  
Vol 78 (9) ◽  
pp. 2438-2443 ◽  
Author(s):  
JG Conboy ◽  
R Shitamoto ◽  
M Parra ◽  
R Winardi ◽  
A Kabra ◽  
...  
Keyword(s):  
Amino Acids ◽  
Mechanical Stability ◽  
Membrane Skeleton ◽  
Actin Binding ◽  
Erythrocyte Morphology ◽  
Protein 4.1 ◽  
Hereditary Elliptocytosis ◽  
Exon Expression ◽  
Amino Acid Peptide ◽  
Skeletal Protein

Abstract Protein 4.1 is an important structural component of the membrane skeleton that helps determine erythrocyte morphology and membrane mechanical properties. In a previous study we identified a case of human hereditary elliptocytosis (HE) in which decreased membrane mechanical stability was due to deletion of 80 amino acids encompassing the entire 10-Kd spectrin-actin binding domain. A portion of this domain (21 amino acids) is encoded by an alternatively spliced exon that is expressed in late but not early erythroid cells. We now report a case of canine HE in which the abnormal phenotype is caused by failure to express this alternative peptide in the mature red blood cell (RBC) membrane skeleton, in conjunction with quantitative deficiency of protein 4.1. Western blotting of RBC membranes from a dog with HE showed a truncated protein 4.1 that did not react with antibodies directed against the alternative peptide. In addition, sequencing of cloned reticulocyte protein 4.1 cDNA showed a precise deletion of 63 nucleotides comprising this exon. Normal dog reticulocytes did express this exon. Expression of this 21 amino acid peptide during erythroid maturation is therefore essential for proper assembly of a mechanically competent membrane skeleton, because RBCs lacking this peptide have unstable membranes.

scholarly journals Hereditary elliptocytosis due to both qualitative and quantitative defects in membrane skeletal protein 4.1

Blood ◽  
1991 ◽  
Vol 78 (9) ◽  
pp. 2438-2443
Author(s):  
JG Conboy ◽  
R Shitamoto ◽  
M Parra ◽  
R Winardi ◽  
A Kabra ◽  
...  
Keyword(s):  
Amino Acids ◽  
Mechanical Stability ◽  
Membrane Skeleton ◽  
Actin Binding ◽  
Erythrocyte Morphology ◽  
Protein 4.1 ◽  
Hereditary Elliptocytosis ◽  
Exon Expression ◽  
Amino Acid Peptide ◽  
Skeletal Protein

Protein 4.1 is an important structural component of the membrane skeleton that helps determine erythrocyte morphology and membrane mechanical properties. In a previous study we identified a case of human hereditary elliptocytosis (HE) in which decreased membrane mechanical stability was due to deletion of 80 amino acids encompassing the entire 10-Kd spectrin-actin binding domain. A portion of this domain (21 amino acids) is encoded by an alternatively spliced exon that is expressed in late but not early erythroid cells. We now report a case of canine HE in which the abnormal phenotype is caused by failure to express this alternative peptide in the mature red blood cell (RBC) membrane skeleton, in conjunction with quantitative deficiency of protein 4.1. Western blotting of RBC membranes from a dog with HE showed a truncated protein 4.1 that did not react with antibodies directed against the alternative peptide. In addition, sequencing of cloned reticulocyte protein 4.1 cDNA showed a precise deletion of 63 nucleotides comprising this exon. Normal dog reticulocytes did express this exon. Expression of this 21 amino acid peptide during erythroid maturation is therefore essential for proper assembly of a mechanically competent membrane skeleton, because RBCs lacking this peptide have unstable membranes.

scholarly journals An analogue of the erythroid membrane skeletal protein 4.1 in nonerythroid cells.

1984 ◽  
Vol 99 (3) ◽  
pp. 886-893 ◽  
Author(s):  
J E Spiegel ◽  
D S Beardsley ◽  
F S Southwick ◽  
S E Lux
Keyword(s):  
Binding Protein ◽  
Protein S ◽  
Membrane Skeleton ◽  
Cross Reactivity ◽  
Lymphoid Cells ◽  
Actin Binding ◽  
Protein 4.1 ◽  
Reactive Protein ◽  
Skeletal Protein ◽  
Associated Proteins

Protein 4.1 is a crucial component of the erythrocyte membrane skeleton. Responsible for the amplification of the spectrin-actin interaction, its presence is required for the maintenance of erythrocyte integrity. We have demonstrated a 4.1-like protein in nonerythroid cells. An antibody was raised to erythrocyte protein 4.1 purified by KCl extraction (Tyler, J. M., W. R. Hargreaves, and D. Branton, 1979, Proc. Natl. Acad. Sci. USA, 76:5192-5196), and used to identify a serologically cross-reactive protein in polymorphonuclear leukocytes, platelets, and lymphoid cells. The cross-reactive protein(s) were localized to various regions of the cells by immunofluorescence microscopy. Quantitative adsorption studies indicated that at least 30-60% of the anti-4.1 antibodies reacted with this protein, demonstrating significant homology between the erythroid and nonerythroid species. A homologous peptide doublet was observed on immunopeptide maps, although there was not complete identity between the two proteins. When compared with erythrocyte protein 4.1, the nonerythroid protein(s) displayed a lower molecular weight--68,000 as compared with 78,000-and did not bind spectrin or the nonerythroid actin-binding protein filamin. There was no detectable cross-reactivity between human acumentin or human tropomyosin-binding protein, which are similarly sized actin-associated proteins, and erythrocyte protein 4.1. The possible origin and significance of 4.1-related protein(s) in nonerythroid cells are discussed.

scholarly journals Disorders of the erythrocyte membrane

2015 ◽  
Vol 9 (4) ◽  
pp. 323
Author(s):  
Sophia Delicou ◽  
Aikaterini Xydaki ◽  
Chryssanthi Kontaxi ◽  
Konstantinos Maragkos
Keyword(s):  
Surface Area ◽  
Erythrocyte Membrane ◽  
Structural Integrity ◽  
Mechanical Stability ◽  
Hereditary Spherocytosis ◽  
Membrane Surface ◽  
Membrane Skeleton ◽  
Inherited Disorders ◽  
Hereditary Elliptocytosis ◽  
Area Loss

Hemolytic anemia due to abnormalities of the erythrocyte membrane comprises an important group of inherited disorders. These include hereditary spherocytosis, hereditary elliptocytosis, hereditary pyropoikilocytosis, and the hereditary stomatocytosis syndromes. The erythrocyte membrane skeleton composed of spectrin, actin, and several other proteins is essential for the maintenance of the erythrocyte shape, reversible deformability, and membrane structural integrity in addition to controlling the lateral mobility of integral membrane proteins. These disorders are characterized by clinical and laboratory heterogeneity and, as evidenced by recent molecular studies, by genetic heterogeneity. Defects in various proteins involved in linking the lipid bilayer to membrane skeleton result in loss in membrane cohesion leading to surface area loss and hereditary spherocytosis while defects in proteins involved in lateral interactions of the spectrin-based skeleton lead to decreased mechanical stability, membrane fragmentation and hereditary elliptocytosis. The disease severity is primarily dependent on the extent of membrane surface area loss. Treatment with splenectomy is curative in most patients.

Mild spherocytic hereditary elliptocytosis and altered levels of α- and γ-adducins in β-adducin-deficient mice

Blood ◽  
2000 ◽  
Vol 95 (12) ◽  
pp. 3978-3985 ◽  
Author(s):  
Andrés F. Muro ◽  
Martı́n L. Marro ◽  
Srećko Gajović ◽  
Fabiola Porro ◽  
Lucio Luzzatto ◽  
...  
Keyword(s):  
Membrane Surface ◽  
Osmotic Fragility ◽  
Membrane Skeleton ◽  
Blood Film ◽  
Mean Corpuscular Hemoglobin ◽  
Messenger Rnas ◽  
Inherited Disorders ◽  
Erythrocyte Morphology ◽  
Mild Phenotype ◽  
Hereditary Elliptocytosis

Abstract The membrane skeleton, a dynamic network of proteins associated with the plasma membrane, determines the shape and mechanical properties of erythrocytes. Deficiencies or defects in membrane skeletal proteins are associated with inherited disorders of erythrocyte morphology and function. Adducin is one of the proteins localized at the spectrin-actin junction of the membrane skeleton. In this work we show that deficiency of β-adducin produces an 80% decrease of -adducin and a fourfold up-regulation of γ-adducin in erythrocytes. β-Adducin or any other isoform generated by translation of abnormally spliced messenger RNAs could not be detected by our antibodies either in ghosts or in cytoplasm of −/− erythrocytes. Actin levels were diminished in mutant mice, suggesting alterations in the actin-spectrin junctional complexes due to the absence of adducin. Elliptocytes, ovalocytes, and occasionally spherocytes were found in the blood film of −/− mice. Hematological values showed an increase in reticulocyte counts and mean corpuscular hemoglobin concentration, decreased mean corpuscular volume and hematocrit, and normal erythrocyte counts that, associated to splenomegaly, indicate that the mice suffer from mild anemia with compensated hemolysis. These modifications are due to a loss of membrane surface and dehydration that result in an increase in the osmotic fragility of red blood cells. The marked alteration in osmotic fragility together with the predominant presence of elliptocytes is reminiscent of the human disorder called spherocytic hereditary elliptocytosis. Our results suggest that the amount of adducin remaining in the mutant animals (presumably γ adducin) could be functional and might account for the mild phenotype.

A Drosophila homologue of membrane-skeleton protein 4.1 is associated with septate junctions and is encoded by the coracle gene

Development ◽  
1994 ◽  
Vol 120 (3) ◽  
pp. 545-557 ◽  
Author(s):  
R.G. Fehon ◽  
I.A. Dawson ◽  
S. Artavanis-Tsakonas
Keyword(s):  
Egf Receptor ◽  
Normal Development ◽  
Membrane Skeleton ◽  
Septate Junction ◽  
Cellular Functions ◽  
Septate Junctions ◽  
Protein 4.1 ◽  
Skeletal Protein ◽  
Developmental Role ◽  
Primary Mutant

Protein 4.1 functions to link transmembrane proteins with the underlying spectrin/actin cytoskeleton. To permit a genetic analysis of the developmental role and cellular functions of this membrane-skeletal protein, we have identified and characterized its Drosophila homologue (termed D4.1). D4.1 is localized to the septate junctions of epithelial cells and is encoded by the coracle gene, a new locus whose primary mutant phenotype is a failure in dorsal closure. In addition, coracle mutations dominantly suppress Ellipse, a hypermorphic allele of the Drosophila EGF-receptor homologue. These data indicate that D4.1 is associated with the septate junction, and suggest that it may play a role in cell-cell interactions that are essential for normal development.

The C-Terminus of Alpha Spectrin Binds Protein 4.2 and Is Necessary for Optimal Spectrin-Actin Binding.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 810-810 ◽  
Author(s):  
Catherine Korsgren ◽  
Connie S. Birkenmeier ◽  
Jane E. Barker ◽  
Luanne L. Peters ◽  
Samuel E. Lux
Keyword(s):  
Amino Acids ◽  
Membrane Skeleton ◽  
Binding Domain ◽  
Actin Binding ◽  
C Terminus ◽  
Actin Binding Domain ◽  
Ef Hand ◽  
Protein 4.2 ◽  
Protein 4.1R ◽  
Β Chain

Abstract The red blood cell (RBC) membrane skeleton is composed principally of short F-actin filaments crosslinked by α2β2-spectrin tetramers with the assistance of protein 4.1R. Actin and 4.1R bind to the actin-binding domain (βABD) at the N-terminus of the spectrin β-chain. The adjacent, C-terminal end of α-spectrin, contains a calmodulin-like domain (αCML, aa 2262–2418) that is also called the EF hand domain and is thought to be inert or vestigial. However, the sph1J/sph1J mouse, which has severe hereditary spherocytosis and unstable RBC membranes, makes a mutant α-spectrin that lacks the last 13 amino acids (αCMLΔC13), showing that the domain has some important function. To investigate this function we “fished” for interacting proteins using glutathione-S-transferase (GST)-fused to the CML domain—either the wildtype (αGST-CML) or sph1J (αGST-CMLΔC13). αGST-CML retrieved protein 4.2 from a 2M Tris HCl extract of spectrin-actin depleted human RBC membranes. Protein 4.2 bound αGST-CML with high affinity (Kd = 2.7 x 10−7M) but did not bind αGST-CMLΔC13. Binding was abolished by 1 mM Ca2+, which converts the CML domain to the liganded conformation. The binding site on protein 4.2 localized, at least partly, to amino acids 411–492. Because red cells lacking protein 4.2 are not as severely affected as sph1J/sph1J RBCs, we also tested the effect of the αCMLΔC13 mutation on spectrin-actin binding. A minispectrin was prepared containing the actin-binding domain plus the first four spectrin repeats of the β-chain, combined with the CML domain (±ΔC13) and the last four repeats of the α-chain. The normal and mutant minispectrins were incubated with protein 4.1R, F-actin, or both proteins. The results were striking. The minispectrin containing the normal CML domain bound actin in the presence of protein 4.1R, but the minispectrin containing the mutant CML domain did not. Similarly, the mutant minispectrin was defective in its ability to bind 125I-4.1R in the presence of a constant amount of F-actin. However, the mutation did not affect binding of the minispectrin to protein 4.1R in the absence of actin. We have not yet tested whether protein 4.2 or Ca2+ modulate the effects of the CML domain on spectrin-actin binding. In summary, these experiments clearly show that the calmodulin-like (EF hand) domain of α-spectrin, which was previously considered inert, binds protein 4.2 and also contributes to spectrin-actin binding in the presence of protein 4.1R. Further experiments will be needed to determine whether the CML domain binds actin directly or strengthens the binding of the adjacent actin-binding domain.

scholarly journals Primary structure and domain organization of human alpha and beta adducin.

1991 ◽  
Vol 115 (3) ◽  
pp. 665-675 ◽  
Author(s):  
R Joshi ◽  
D M Gilligan ◽  
E Otto ◽  
T McLaughlin ◽  
V Bennett
Keyword(s):  
Amino Acids ◽  
Sequence Similarity ◽  
Complete Sequence ◽  
Amino Acid Sequences ◽  
Actin Binding ◽  
Cell Contact ◽  
Binding Motif ◽  
Rat Tissues ◽  
Erythroleukemia Cells ◽  
Skeletal Protein

Adducin is a membrane-skeletal protein which is a candidate to promote assembly of a spectrin-actin network in erythrocytes and at sites of cell-cell contact in epithelial tissues. The complete sequence of both subunits of human adducin, alpha (737 amino acids), and beta (726 amino acids) has been deduced by analysis of the cDNAs. The two subunits have strikingly conserved amino acid sequences with 49% identity and 66% similarity, suggesting evolution by gene duplication. Each adducin subunit has three distinct domains: a 39-kD NH2-terminal globular protease-resistant domain, connected by a 9-kD domain to a 33-kD COOH-terminal protease-sensitive tail comprised almost entirely of hydrophilic amino acids. The tail is responsible for the high frictional ratio of adducin noted previously, and was visualized by EM. The head domains of both adducin subunits exhibit a limited sequence similarity with the NH2-terminal actin-binding motif present in members of the spectrin superfamily and actin gelation proteins. The COOH-termini of both subunits contain an identical, highly basic stretch of 22 amino acids with sequence similarity to the MARCKS protein. Predicted sites of phosphorylation by protein kinase C include the COOH-terminus and sites at the junction of the head and tail. Northern blot analysis of mRNA from rat tissues, K562 erythroleukemia cells and reticulocytes has shown that alpha adducin is expressed in all the tissues tested as a single message size of 4 kb. In contrast, beta adducin shows tissue specific variability in size of mRNA and level of expression. A striking divergence between alpha and beta mRNAs was noted in reticulocytes, where alpha adducin mRNA is present in at least 20-fold higher levels than that of beta adducin. The beta subunit thus is a candidate to perform a limiting role in assembly of functional adducin molecules.

scholarly journals Identification of a functional role for human erythrocyte sialoglycoproteins beta and gamma

Blood ◽  
1987 ◽  
Vol 69 (4) ◽  
pp. 1068-1072
Author(s):  
ME Reid ◽  
JA Chasis ◽  
N Mohandas
Keyword(s):  
Erythrocyte Membrane ◽  
Material Properties ◽  
Functional Role ◽  
Mechanical Stability ◽  
Membrane Skeleton ◽  
Membrane Properties ◽  
Membrane Material ◽  
Skeletal Protein ◽  
Alpha Beta ◽  
Normal Erythrocyte

Four distinct erythrocyte membrane sialoglycoproteins (SGPs) denoted alpha, beta, gamma, and delta have been described, but their functions have not yet been defined. Recent evidence suggests that several of these SGPs associate with membrane skeletal proteins. Because the membrane skeletal protein network plays an important role in regulating the membrane material properties of deformability and mechanical stability, we wanted to determine whether the SGPs, through their interaction with the membrane skeleton, can modulate these membrane properties. We measured membrane mechanical stability and membrane deformability of erythrocytes that were deficient in either alpha, or delta or beta and gamma SGPs. Only erythrocytes deficient in beta and gamma SGP had altered membrane properties, as evidenced by marked decreases in both membrane mechanical stability (50% of normal) and membrane deformability (40% of normal). Erythrocytes deficient in either alpha or delta SGP had normal deformability and stability. Based on these data, we suggest that an interaction of beta and/or gamma SGP with the membrane skeleton plays a functionally important role in regulating normal erythrocyte membrane properties.

Mild spherocytic hereditary elliptocytosis and altered levels of α- and γ-adducins in β-adducin-deficient mice

Blood ◽  
2000 ◽  
Vol 95 (12) ◽  
pp. 3978-3985 ◽  
Author(s):  
Andrés F. Muro ◽  
Martı́n L. Marro ◽  
Srećko Gajović ◽  
Fabiola Porro ◽  
Lucio Luzzatto ◽  
...  
Keyword(s):  
Membrane Surface ◽  
Osmotic Fragility ◽  
Membrane Skeleton ◽  
Blood Film ◽  
Mean Corpuscular Hemoglobin ◽  
Messenger Rnas ◽  
Inherited Disorders ◽  
Erythrocyte Morphology ◽  
Mild Phenotype ◽  
Hereditary Elliptocytosis

The membrane skeleton, a dynamic network of proteins associated with the plasma membrane, determines the shape and mechanical properties of erythrocytes. Deficiencies or defects in membrane skeletal proteins are associated with inherited disorders of erythrocyte morphology and function. Adducin is one of the proteins localized at the spectrin-actin junction of the membrane skeleton. In this work we show that deficiency of β-adducin produces an 80% decrease of -adducin and a fourfold up-regulation of γ-adducin in erythrocytes. β-Adducin or any other isoform generated by translation of abnormally spliced messenger RNAs could not be detected by our antibodies either in ghosts or in cytoplasm of −/− erythrocytes. Actin levels were diminished in mutant mice, suggesting alterations in the actin-spectrin junctional complexes due to the absence of adducin. Elliptocytes, ovalocytes, and occasionally spherocytes were found in the blood film of −/− mice. Hematological values showed an increase in reticulocyte counts and mean corpuscular hemoglobin concentration, decreased mean corpuscular volume and hematocrit, and normal erythrocyte counts that, associated to splenomegaly, indicate that the mice suffer from mild anemia with compensated hemolysis. These modifications are due to a loss of membrane surface and dehydration that result in an increase in the osmotic fragility of red blood cells. The marked alteration in osmotic fragility together with the predominant presence of elliptocytes is reminiscent of the human disorder called spherocytic hereditary elliptocytosis. Our results suggest that the amount of adducin remaining in the mutant animals (presumably γ adducin) could be functional and might account for the mild phenotype.

scholarly journals A malaria membrane skeletal protein is essential for normal morphogenesis, motility, and infectivity of sporozoites

2004 ◽  
Vol 167 (3) ◽  
pp. 425-432 ◽  
Author(s):  
Emad I. Khater ◽  
Robert E. Sinden ◽  
Johannes T. Dessens
Keyword(s):  
Cell Shape ◽  
Mechanical Stability ◽  
Membrane Skeleton ◽  
Apicomplexan Parasites ◽  
Membrane Complex ◽  
Skeletal Protein ◽  
Complex Protein ◽  
Parasite Biology ◽  
Inner Membrane Complex ◽  
Membrane Skeletons

Membrane skeletons are structural elements that provide mechanical support to the plasma membrane and define cell shape. Here, we identify and characterize a putative protein component of the membrane skeleton of the malaria parasite. The protein, named PbIMC1a, is the structural orthologue of the Toxoplasma gondii inner membrane complex protein 1 (TgIMC1), a component of the membrane skeleton in tachyzoites. Using targeted gene disruption in the rodent malaria species Plasmodium berghei, we show that PbIMC1a is involved in sporozoite development, is necessary for providing normal sporozoite cell shape and mechanical stability, and is essential for sporozoite infectivity in insect and vertebrate hosts. Knockout of PbIMC1a protein expression reduces, but does not abolish, sporozoite gliding locomotion. We identify a family of proteins related to PbIMC1a in Plasmodium and other apicomplexan parasites. These results provide new functional insight in the role of membrane skeletons in apicomplexan parasite biology.

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