Abstract
Differential display analysis was used to search for novel radiation-inducible transcripts in human cells. Normal human or radiosensitive ataxia-telangiectasia (AT) derived fibroblasts were X-ray (6 Gy)-irradiated and total RNA was extracted 3 hours later. For differential display analysis, three oligo dT-based anchor primers and 20 arbitrary primers were used. A transcript whose expression was significantly elevated after irradiation in normal cells but not in AT cells was excised from the gel, PCR-amplified and cloned in pGEM-T Easy vector. The kinetics of transcriptional response was analyzed further by quantitative PCR method using the Light Cycler apparatus. The increase of the transcript was seen around 1 hour after 6 Gy exposure, and the increase was detectable as low as 0.5 Gy. The ATM status may not be the sole factor for this response, because some ATM-proficient tumor cell lines lacked this response. The transcript was derived from a gene located on human chromosome 12. Similar sequence was not found within the homologous region on mouse chromosome, suggesting this gene may have a recent evolutionary history. [J Radiat Res 44:445 (2003)]
