Expression, purification, and characterization of human hemoglobins Gower-1 (ζ2ε2), Gower-2 (α2ε2), and Portland-2 (ζ2β2) assembled in complex transgenic–knockout mice

摘要: Embryonic ζ- and e-globin subunits assemble with each other adult α- β-globin into hemoglobin heterotetramers in both primitive definitive erythrocytes. The properties of these hemoglobins—Hbs Gower-1 (ζ2e2), Gower-2 (α2e2), Portland-2 (ζ2β2)—have been incompletely described as they are difficult to obtain quantity from either primary human tissue or conventional expression systems. generation complex transgenic–knockout mice that express hemoglobins at levels between 24% 70% is described, efficient methods for their purification mouse hemolysates. Key physiological characteristics—including P50, Hill coefficient, Bohr effect, affinity 2,3-BPG—were established the 3 hemoglobins. stability face mechanical, thermal, chemical stresses was also determined. Analyses indicate ζ-for-α exchange distinguishing Hb A alters O2-transport capacity by increasing its P50 decreasing effect. By comparison, e-for-β has little impact on same functional parameters. Gower-1, assembled entirely embryonic subunits, displays an elevated level, a reduced increased 2,3-BPG binding compared A. data support hypothesis Gower-2, reactivated e globin individuals defined hemoglobinopathies thalassemias, would serve physiologically acceptable substitute deficient dysfunctional In addition, unexpected call question common role development.