Increased synthesis of mouse minor hemoglobin in erythroid colonies: a cellular model for hemoglobin regulation.

Globin synthesis was examined in mouse erythroid colonies. Bone marrow cells from DBA/2J adults were cultured in methylcellulose and labeled with 3H-leucine; globin synthesis ratios were determined following electrophoresis of lysates on polyacrylamide gels containing urea, acid, and Triton X-100. Colonies derived from the immature progenitor cells, BFU-E and CFU-E, produced close to 40% beta mi of total beta, while cluster-forming units, erythroblasts, and reticulocytes synthesized approximately 30% beta mi. Thus, beta mi synthesis decreased with increasing maturity of the erythroid compartment being examined, qualitatively resembling the decrease in fetal hemoglobin between BFU-E and erythrocytes in human adults. The mouse system described here thus provides a small animal model for studies of changes in hemoglobin expression during erythroid development.