Bilayer/cytoskeleton interactions in lipid-symmetric erythrocytes assessed by a photoactivable phospholipid analogue

Journal Article · Tue Aug 06 00:00:00 EDT 1991 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00245a012· OSTI ID:5701916

Pradhan, D; Schlegel, R A ^[1]; Williamson, P ^[2]

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1. Pennsylvania State Univ., University Park (United States)
2. Amherst Coll., MA (United States)

Two mechanisms have been proposed for maintenance of transbilayer phospholipid asymmetry in the erythrocyte plasma membrane, one involving specific interactions between the aminophospholipids of the inner leaflet of the bilayer and the cytoskeleton, particularly spectrin, and the other involving the aminophospholipid translocase. If the former mechanism is correct, then erythrocytes which have lost their asymmetric distribution of phospholipids should display altered bilayer/cytoskeleton interactions. To test this possibility, normal erythrocytes, erythrocytes from patients with chronic myelogenous leukemia or sickle disease, and lipid-symmetric and -asymmetric erythrocyte ghosts were labeled with the radioactive photoactivable analogue of phosphatidylethanolamine, 2-(2-azido-4-nitrobenzoyl)-1-acyl-sn-glycero-3-phospho({sup 14}C) ethanolamine (({sup 14}C)AzPE), previously shown to label cytoskeletal proteins from the bilayer. The labeling pattern of cytoskeletal proteins in pathologic erythrocytes and lipid-asymmetric erythrocyte ghosts was indistinguishable from normal erythrocytes, indicating that the probe detects no differences in bilayer/cytoskeleton interactions in these cells. In contrast, in lipid-symmetric erythrocyte ghosts, labeling of bands 4.1 and 4.2 and actin, and to a lesser extent ankyrin, by ({sup 14}C)AzPE was considerably reduced. Significantly, however, labeling of spectrin was unaltered in the lipid-symmetric cells. These results do not support a model in which spectrin is involved in the maintenance of an asymmetric distribution of phospholipids in erythrocytes.

• OSTI ID: 5701916
• Journal Information: Biochemistry; (United States), Vol. 30:31; ISSN 0006-2960
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
AMINES
BIOCHEMISTRY
PHOSPHOLIPIDS
SUBCELLULAR DISTRIBUTION
ASYMMETRY
CARBON 14 COMPOUNDS
CELL MEMBRANES
ELECTROPHORESIS
ERYTHROCYTES
LEUKEMIA
SICKLE CELL ANEMIA
ANEMIAS
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CARBON COMPOUNDS
CELL CONSTITUENTS
CHEMISTRY
DISEASES
DISTRIBUTION
ESTERS
HEMIC DISEASES
IMMUNE SYSTEM DISEASES
LABELLED COMPOUNDS
LIPIDS
MATERIALS
MEMBRANES
NEOPLASMS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
SYMPTOMS
550201* - Biochemistry- Tracer Techniques