scholarly journals Regulatory factors specific for adult and embryonic globin genes may govern their expression in erythroleukemia cells

Blood ◽  
1985 ◽  
Vol 65 (3) ◽  
pp. 705-712
Author(s):  
NP Anagnou ◽  
TY Yuan ◽  
E Lim ◽  
J Helder ◽  
S Wieder ◽  
...  

In order to test if trans-acting regulatory factors specific for globin genes of the adult and embryonic stages of development exist in erythroid cells, transcriptionally active embryonic and adult globin genes on the same chromosome were transferred by cell fusion from the human leukemia cell K562 into phenotypically adult mouse erythroleukemia cells. Restriction-fragment-length polymorphisms of the K562 zeta (embryonic) globin genes were used to establish that all three copies of human chromosome 16 present in the K562 cell showed the same pattern of human globin gene expression after transfer to the mouse erythroleukemia cell. Adult (alpha) but not embryonic (zeta) human globin mRNA was detected in all nine of the independently derived mouse erythroleukemia hybrid cells, each of which contained human chromosome 16. Restriction endonuclease studies of the K562 alpha- and zeta-globin genes after transfer into the mouse erythroleukemia cell showed no evidence of rearrangements or deletions that could explain this loss of zeta-globin gene expression. These data suggest that regulation of globin gene expression in these erythroleukemia cells involves trans-acting regulatory factors specific for the adult and embryonic stages of development.

Blood ◽  
1985 ◽  
Vol 65 (3) ◽  
pp. 705-712 ◽  
Author(s):  
NP Anagnou ◽  
TY Yuan ◽  
E Lim ◽  
J Helder ◽  
S Wieder ◽  
...  

Abstract In order to test if trans-acting regulatory factors specific for globin genes of the adult and embryonic stages of development exist in erythroid cells, transcriptionally active embryonic and adult globin genes on the same chromosome were transferred by cell fusion from the human leukemia cell K562 into phenotypically adult mouse erythroleukemia cells. Restriction-fragment-length polymorphisms of the K562 zeta (embryonic) globin genes were used to establish that all three copies of human chromosome 16 present in the K562 cell showed the same pattern of human globin gene expression after transfer to the mouse erythroleukemia cell. Adult (alpha) but not embryonic (zeta) human globin mRNA was detected in all nine of the independently derived mouse erythroleukemia hybrid cells, each of which contained human chromosome 16. Restriction endonuclease studies of the K562 alpha- and zeta-globin genes after transfer into the mouse erythroleukemia cell showed no evidence of rearrangements or deletions that could explain this loss of zeta-globin gene expression. These data suggest that regulation of globin gene expression in these erythroleukemia cells involves trans-acting regulatory factors specific for the adult and embryonic stages of development.


Blood ◽  
1998 ◽  
Vol 92 (9) ◽  
pp. 3416-3421 ◽  
Author(s):  
E. Skarpidi ◽  
G. Vassilopoulos ◽  
G. Stamatoyannopoulos ◽  
Q. Li

To examine whether transfer of γ globin genes into mouse erythroleukemia cells can be used for the analysis of regulatory elements of γ globin gene promoter, Aγ gene constructs carrying promoter truncations that have been previously analyzed in transgenic mice were used for production of stably transfected mouse erythroleukemia (MEL) cell clones and pools. We found that constructs, which contain a microlocus control region (μLCR) that efficiently protects globin gene expression from the effects of the position of integration in transgenic mice, display position-dependent globin gene expression in MEL cell clones. Aγ globin gene expression among MEL cell clones carrying the μLCR(−201)Aγ and μLCR(−382)Aγ gene constructs ranged 15.5-fold and 17.6-fold, respectively, and there was no correlation between theAγ mRNA levels and the copies of the transgene (r= .28, P = .18). There was significant variation in per copy Aγ globin gene expression among MEL cell pools composed of 10 clones, but not among pools composed of 50 clones, indicating that position effects are averaged in pools composed by large numbers of clones. The overall pattern of Aγ globin gene expression in MEL cell pools resembled that observed in transgenic mice indicating that MEL cell transfections can be used in the study ofcis elements controlling γ globin gene expression. MEL cell transfections, however, are not appropriate for investigation of cis elements, which either sensitize or protect the globin transgenes from position effects. © 1998 by The American Society of Hematology.


Blood ◽  
1998 ◽  
Vol 92 (9) ◽  
pp. 3416-3421 ◽  
Author(s):  
E. Skarpidi ◽  
G. Vassilopoulos ◽  
G. Stamatoyannopoulos ◽  
Q. Li

Abstract To examine whether transfer of γ globin genes into mouse erythroleukemia cells can be used for the analysis of regulatory elements of γ globin gene promoter, Aγ gene constructs carrying promoter truncations that have been previously analyzed in transgenic mice were used for production of stably transfected mouse erythroleukemia (MEL) cell clones and pools. We found that constructs, which contain a microlocus control region (μLCR) that efficiently protects globin gene expression from the effects of the position of integration in transgenic mice, display position-dependent globin gene expression in MEL cell clones. Aγ globin gene expression among MEL cell clones carrying the μLCR(−201)Aγ and μLCR(−382)Aγ gene constructs ranged 15.5-fold and 17.6-fold, respectively, and there was no correlation between theAγ mRNA levels and the copies of the transgene (r= .28, P = .18). There was significant variation in per copy Aγ globin gene expression among MEL cell pools composed of 10 clones, but not among pools composed of 50 clones, indicating that position effects are averaged in pools composed by large numbers of clones. The overall pattern of Aγ globin gene expression in MEL cell pools resembled that observed in transgenic mice indicating that MEL cell transfections can be used in the study ofcis elements controlling γ globin gene expression. MEL cell transfections, however, are not appropriate for investigation of cis elements, which either sensitize or protect the globin transgenes from position effects. © 1998 by The American Society of Hematology.


2018 ◽  
Vol 38 (19) ◽  
Author(s):  
Yong Shen ◽  
MacLean A. Bassett ◽  
Aishwarya Gurumurthy ◽  
Rukiye Nar ◽  
Isaac J. Knudson ◽  
...  

ABSTRACT The organization of the five β-type globin genes on chromosome 11 reflects the timing of expression during erythroid cell development, with the embryonic ε-globin gene being located at the 5′ end, followed by the two fetal γ-globin genes, and with the adult β- and δ-globin genes being located at the 3′ end. Here, we functionally characterized a DNase I-hypersensitive site (HS) located 4 kb upstream of the Gγ-globin gene (HBG-4kb HS). This site is occupied by transcription factors USF1, USF2, EGR1, MafK, and NF-E2 in the human erythroleukemia cell line K562 and exhibits histone modifications typical for enhancers. We generated a synthetic zinc finger (ZF) DNA-binding domain targeting the HBG-4kb HS (HBG-4kb ZF). The HBG-4kb ZF interacted with the target site in vitro and in the context of cells with a high affinity and specificity. Direct delivery of the HBG-4kb ZF to K562 and primary human erythroid cells caused a reduction in γ-globin gene expression which was associated with decreased binding of transcription factors and active histone marks at and downstream of the HS. The data demonstrate that the HBG-4kb HS is important for fetal globin production and suggest that it may act by opening chromatin in a directional manner.


1976 ◽  
Vol 2 (4) ◽  
pp. 373-384 ◽  
Author(s):  
Albert Deisseroth ◽  
Ramon Velez ◽  
Robert D. Burk ◽  
John Minna ◽  
W. French Anderson ◽  
...  

Cell ◽  
1984 ◽  
Vol 38 (1) ◽  
pp. 251-263 ◽  
Author(s):  
Patrick Charnay ◽  
Richard Treisman ◽  
Pamela Mellon ◽  
Moses Chao ◽  
Richard Axel ◽  
...  

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