The activation of a specific DNA binding protein by neutron irradiation.
OBJECTIVE
To determine whether the quality of ionizing radiation is critical for activation of a radiation-specific DNA binding protein.


METHODS
We have previously shown that after exposing Epstein Barr virus-transformed lymphoblastoid cells to ionizing radiation, a specific DNA binding factor appears in the nucleus apparently as a result of translocation from the cytoplasm. This protein binds to a number of different genomic sequences and a consensus motif has been identified. Because the protein was not activated by UV light, it was of interest whether high linear energy transfer (LET) radiation was capable of activation.


RESULTS
We describe here the activation of a specific DNA binding protein by high LET neutron radiation. The protein binds a region adjacent to and overlapping with the distal repeat within a 179 base-pair fragment of the well-characterized Simian Virus (SV40) bidirectional promoter/enhancer element. The appearance of the DNA binding activity was dose dependent and reached a maximum level by 90 min postirradiation. A reduction in DNA binding activity was evident at later times after irradiation.


CONCLUSIONS
The specific nature of this response and the rapidity of activation may indicate a pivotal role for this protein in repair or in some other aspect of the cellular response to radiation damage.
Teale
B
B
Queensland Cancer Fund Research Unit, Queensland Institute of Medical Research, Bancroft Centre, Brisbane, Australia.
Singh
S
S
Cohen
D
D
Lavin
M F
MF
D001483:Base Sequence; D002461:Cell Line, Transformed; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D018499:Linear Energy Transfer; D008969:Molecular Sequence Data; D009502:Neutrons; D011401:Promoter Regions, Genetic / Q000235:genetics*; D013539:Simian virus 40 / Q000235:genetics; D054334:Viral Regulatory and Accessory Proteins / Q000096:biosynthesis / Q000235:genetics / Q000528:radiation effects*
D004268:DNA-Binding Proteins; D054334:Viral Regulatory and Accessory Proteins