Expression of embryonic haemoglobin in tsAEV-transformed embryonic erythroid cells during temperature-induced...

Cells prepared from 1-day-old chick blastoderms were infected with a temperature-sensitive mutant of avian erythroblastosis virus (tsAEV). Clonal strains of transformed erythroblasts were isolated from the infected blastoderm cells. By shift to the nonpermissive temperature, these cells could be induced to differentiate into erythrocyte-like cells which expressed embryonic haemoglobins. Embryonic haemoglobins could not be detected in tsAEV-transformed erythroblasts from adult bone marrow when induced to differentiate under the same conditions. In contrast to normal primitive erythrocytes, tsAEV-infected embryonic erythroblasts differentiated in vitro expressed also adult haemoglobin. These results suggest an influence of the haematopoietic environment on the switch from embryonic to adult erythrocytes.