Dataset Information

Phase separation and crystallization of hemoglobin C in transgenic mouse and human erythrocytes.

ABSTRACT: Individuals expressing hemoglobin C (beta6 Glu-->Lys) present red blood cells (RBC) with intraerythrocytic crystals that form when hemoglobin (Hb) is oxygenated. Our earlier in vitro liquid-liquid (L-L) phase separation studies demonstrated that liganded HbC exhibits a stronger net intermolecular attraction with a longer range than liganded HbS or HbA, and that L-L phase separation preceded and enhanced crystallization. We now present evidence for the role of phase separation in HbC crystallization in the RBC, and the role of the RBC membrane as a nucleation center. RBC obtained from both human homozygous HbC patients and transgenic mice expressing only human HbC were studied by bright-field and differential interference contrast video-enhanced microscopy. RBC were exposed to hypertonic NaCl solution (1.5-3%) to induce crystallization within an appropriate experimental time frame. L-L phase separation occurred inside the RBC, which in turn enhanced the formation of intraerythrocytic crystals. RBC L-L phase separation and crystallization comply with the thermodynamic and kinetics laws established through in vitro studies of phase transformations. This is the first report, to the best of our knowledge, to capture a temporal view of intraerythrocytic HbC phase separation, crystal formation, and dissolution.

SUBMITTER: Canterino JE

PROVIDER: S-EPMC2553125 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Phase separation and crystallization of hemoglobin C in transgenic mouse and human erythrocytes.

Canterino Joseph E JE Galkin Oleg O Vekilov Peter G PG Hirsch Rhoda Elison RE

Biophysical journal 20080711 8

Individuals expressing hemoglobin C (beta6 Glu-->Lys) present red blood cells (RBC) with intraerythrocytic crystals that form when hemoglobin (Hb) is oxygenated. Our earlier in vitro liquid-liquid (L-L) phase separation studies demonstrated that liganded HbC exhibits a stronger net intermolecular attraction with a longer range than liganded HbS or HbA, and that L-L phase separation preceded and enhanced crystallization. We now present evidence for the role of phase separation in HbC crystallizat ...[more]

PMID: 18621841

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Dataset Information

Phase separation and crystallization of hemoglobin C in transgenic mouse and human erythrocytes.

Publications

Phase separation and crystallization of hemoglobin C in transgenic mouse and human erythrocytes.

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