Specific globin mRNAs in human erythroleukemia (K562) cells

Abstract

Specific globin mRNA accumulation was quantitated in several lines of K562 cells in the absence and the presence of hemin. Using specific cloned DNA probes, the amounts of zeta, alpha, epsilon and gamma mRNAs were shown to be increased 2–3-fold in the presence of 20 microM hemin. No delta- or beta-globin mRNAs were detectable in any of the lines. In one line, Bos, there was a marked decrease in epsilon-globin mRNA, which increased with hemin, although still to much lower levels than in the other lines. The decreased epsilon-globin mRNA accumulation in Bos is shown to be due to decreased epsilon-globin gene transcription.

Fetal hemoglobin induction during decitabine treatment of elderly patients with high-risk myelodysplastic syndrome or acute myeloid leukemia: a potential dynamic biomarker of outcome

“…Cells were treated with three 24-h pulses of 100 and 20 nM decitabine (Sigma Aldrich) and harvested 144 h after the first treatment, as described previously. 20 Hemin (Sigma Aldrich), a positive control for induction of erythroid differentiation, 21 was added to the culture medium at a final concentration of 50 mM. 22 Cell viability was tested by 0.4% trypan blue staining.…”

Nuclease‐stimulated homologous recombination at the human β‐globin gene

“…The equivalent figure in iPSCs was only 0.3%, however, even after selecting against nontargeted integration with ganciclovir . This difference is difficult to explain in terms of HBB transcription that is silent both in iPSCs and in K562 cells but may reflect an apparent tendency for the targeted drug‐resistance gene in iPSCs cells to undergo silencing . Alternatively, it may reflect a favourable HR/NHEJ ratio in K562 compared to iPSCs.…”

Transacting regulation ofβglobin gene expression in erythroleukemia (K562) cells

“…One strain of K562, called K562 Bos, contains very low amounts of £ globin mRNA and protein. The low level of E globin mRNA in K562 Bos and the absence of B globin mRNA in all K562 strains is due to the lack of transcription of these genes (9,10). The absence of B globin gene transcription is not due to a gene deletion (2,5); in fact, a K562 B globin gene is expressed when isolated and tested in a transient expression assay (1,2).…”