Disproportional synthesis of the adult duck's two hemoglobins during acute anemia.

Concurrent synthesis of two or more hemoglobins occurs in normal man, the human hemoglobinopathies, and certain animal species. Duck erythrocytes produced in response to acutely induced anemic hypoxia (hemolysis or blood loss) contained reciprocally altered proportions of Hb I (alpha(2) (I) beta(2) (I)) and Hb II (alpha(2) (II) beta(2) (II)); the relative proportion of Hb II was 50-100% increased. Relative rates of synthesis of the two hemoglobins remained proportional to their new concentrations throughout erythroid maturation. This information favors the proposal that relatively increased activity, not delayed decay, of biosynthetic processes responsible for net synthesis of Hb II had occurred. These studies support the concept that the individual biosyntheses of multiple hemoglobins, presumably under genetic control, are potentially manipulable, and they provide evidence for one mechanism leading in a reproducible fashion to alterations in net synthesis in vivo.