cDNA cloning and transcriptional controlling of a novel low dose radiation-induced gene and its function analysis.

Objective To clone a novel low dose radiation\|induced gene (LRIGx) and study its function as well as its transcriptional changes after irradiation. Methods Its cDNA was obtained by DDRT\|PCR and RACE techniques.Northern blot hybridization was used to investigate the gene transcription.Bioinformatics was employed to analysis structure and function of this gene. Results LRIGx cDNA was cloned.The sequence of LRIGx was identical to a DNA clone located in human chromosome 20 q 11\^2\|12.Bioinformatics analysis predicted an encoded protein with a conserved helicase domain.Northern analysis revealed a ～8 5 kb transcript which was induced after 0 2 Gy as well as 0 02 Gy irradiation,and the transcript level was increased 5 times at 4 h after 0\^2 Gy irradiation.The induced level of LRIGx transcript by 2\^0 Gy high dose was lower than by 0 2 Gy. Conclusion A novel low dose radiation\|induced gene has been cloned.It encodes a protein with a conserved helicase domain that could involve in DNA metabolism in the cellular process of radiation response.\;