Notably, although hemoglobin-synthesizing blood cells have the highest iron need in the human body, no significant impact on hemoglobin production was observed in the MEL (murine erythroleukemia) model of differentiating erythroid cells.
Plasmid transfection studies in erythroid MEL (murine erythroleukemia) cells demonstrated the HPFH2 element could function synergistically with the beta-globin locus control region to enhance the expression of an Agamma-globin gene with a truncated -382 bp promoter.
Evidence supporting such mechanisms has been derived from studying bone marrow leukemiogenesis and analyzing differentiation of leukemic cell lines in culture that serve as models of erythroleukemic (murine erythroleukemia [MEL] and human leukemia [K562] cells) and myeloid (human promyelocytic leukemia [HL-60] cells) cell maturation.
In non-B cells (murine erythroleukemia cells [MEL]), previous studies of segments within the mouse Igh locus demonstrated that DNA replication likely initiated downstream of the Igh gene cluster.
In mouse MELerythroleukemia cells, p16INK4a associates preferentially with cdk6 under conditions where cdk4 and cdk6 are coexpressed at equivalent levels.
Murine erythroleukemia (MEL or Friend) cells grown in culture and induced to differentiate into cells resembling orthochromatic normoblasts provide a suitable system for uncovering molecular and cellular mechanisms of hemopoiesis and for understanding globin gene regulation.