1: Radiat Res. 1998 Dec;150(6):663-72. 

BIGEL analysis of gene expression in HL60 cells exposed to X rays or 60 Hz
magnetic fields.

Balcer-Kubiczek EK, Zhang XF, Han LH, Harrison GH, Davis CC, Zhou XJ, Ioffe V,
McCready WA, Abraham JM, Meltzer SJ.

Department of Radiation Oncology, School of Medicine; Veterans Affairs Hospital,
Baltimore, Maryland 21201, USA.

We screened a panel of 1,920 randomly selected cDNAs to discover genes that are
differentially expressed in HL60 cells exposed to 60 Hz magnetic fields (2 mT)
or X rays (5 Gy) compared to unexposed cells. Identification of these clones was
accomplished using our two-gel cDNA library screening method (BIGEL). Eighteen
cDNAs differentially expressed in X-irradiated compared to control HL60 cells
were recovered from a panel of 1,920 clones. Differential expression in
experimental compared to control cells was confirmed independently by Northern
blotting of paired total RNA samples hybridized to each of the 18 clone-specific
cDNA probes. DNA sequencing revealed that 15 of the 18 cDNA clones produced
matches with the database for genes related to cell growth, protein synthesis,
energy metabolism, oxidative stress or apoptosis (including MYC, neuroleukin,
copper zinc-dependent superoxide dismutase, TC4 RAS-like protein, peptide
elongation factor 1alpha, BNIP3, GATA3, NF45, cytochrome c oxidase II and
triosephosphate isomerase mRNAs). In contrast, BIGEL analysis of the same 1,920
cDNAs revealed no differences greater than 1.5-fold in expression levels in
magnetic-field compared to sham-exposed cells. Magnetic-field-exposed and
control samples were analyzed further for the presence of mRNA encoding
X-ray-responsive genes by hybridization of the 18 specific cDNA probes to RNA
from exposed and control HL60 cells. Our results suggest that differential gene
expression is induced in approximately 1% of a random pool of cDNAs by ionizing
radiation but not by 60 Hz magnetic fields under the present experimental
conditions.

PMID: 9840186 [PubMed - indexed for MEDLINE]


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2: EMBO J. 1996 Jan 15;15(2):319-33. 

GATA transcription factors associate with a novel class of nuclear bodies in
erythroblasts and megakaryocytes.

Elefanty AG, Antoniou M, Custodio N, Carmo-Fonseca M, Grosveld FG.

National Institute for Medical Research, UK.

The nuclear distribution of GATA transcription factors in murine haemopoietic
cells was examined by indirect immunofluorescence. Specific bright foci of
GATA-1 fluorescence were observed in erythroleukaemia cells and primary murine
erythroblasts and megakaryocytes, in addition to diffuse nucleoplasmic
localization. These foci, which were preferentially found adjacent to nucleoli
or at the nuclear periphery, did not represent sites of active transcription or
binding of GATA-1 to consensus sites in the beta-globin loci. Immunoelectron
microscopy demonstrated the presence of intensely labelled structures likely to
represent the GATA-1 foci seen by immunofluorescence. The GATA-1 nuclear bodies
differed from previously described nuclear structures and there was no
co-localization with nuclear antigens involved in RNA processing or other
ubiquitous (Spl, c-Jun and TBP) or haemopoietic (NF-E2) transcription factors.
Interestingly, GATA-2 and GATA-3 proteins also localized to the same nuclear
bodies in cell lines co-expressing GATA-1 and -2 or GATA-1 and -3 gene products.
This pattern of distribution is, thus far, unique to the GATA transcription
factors and suggests a protein-protein interaction with other components of the
nuclear bodies via the GATA zinc finger domain.

PMID: 8617207 [PubMed - indexed for MEDLINE]


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