title: Dose-dependent and gender-related radiation-induced transcription alterations of Gadd45a and Ier5 inhuman lymphocytes exposed to gamma ray emitted by (60)Co.
abstract: Growth arrest DNA damage-inducible 45a gene (Gadd45a) and immediate early response gene 5 (Ier5) have been emphasised as ideal radiation biomarkers in several reports. However, some aspects of radiation-induced transcriptional alterations of these genes are unknown. In this study, gender-dependency and dose-dependency as two factors that may affect radiation-induced transcription of Gadd45a and Ier5 genes were investigated. Human lymphocyte cells from six healthy voluntary blood donors (three women and three men) were irradiated in vitro with doses of 0.5-4.0 Gy from a (60)Co source and RNA isolated 4 h later using the High Pure RNA Isolation Kit. Dose and gender dependency of radiation-induced transcriptional alterations of Gadd45a and Ier5 genes were studied by quantitative real-time polymerase chain reaction. The results showed that as a whole, Gadd45a and Ier5 gave responses to gamma rays, while the responses were independent of radiation doses. Therefore, regardless of radiation dose, Gadd45a and Ier5 can be considered potential radiation biomarkers. Besides, although radiation-induced transcriptional alterations of Gadd45a in female and male lymphocyte samples were insignificant at 0.5 Gy, at other doses, their quantities in female samples were at a significantly higher level than in male samples. Radiation-induced transcription of Ier5 of females samples had a reduction in comparison with male samples at 1 and 2 Gy, but at doses of 0.5 and 4 Gy, females were significantly more susceptible to radiation-induced transcriptional alteration of Ier5.
authors.affiliation: Applied Neuroscience Research Center, Department of Physiology and Biophysics, Baqiyatallah University of Medical Sciences, Tehran, Iran. tavakoli@ibb.ut.ac.ir
authors.forename: Hassan
authors.initials: H
authors.lastname: Tavakoli
authors.forename: Mahdi
authors.initials: M
authors.lastname: Manoochehri
authors.forename: Sayed Mahdi
authors.initials: SM
authors.lastname: Modarres Mosalla
authors.forename: Mostafa
authors.initials: M
authors.lastname: Ghafori
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Karimi
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D018797:Cell Cycle Proteins / Q000235:genetics*; D003037:Cobalt Radioisotopes / Q000009:adverse effects*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005720:Gamma Rays / Q000009:adverse effects*; D005783:Gender Identity; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics*; D008214:Lymphocytes / Q000528:radiation effects*; D008297:Male; D009687:Nuclear Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000528:radiation effects*; D060888:Real-Time Polymerase Chain Reaction; D014158:Transcription, Genetic / Q000528:radiation effects*; D000097642:GADD45 Proteins
chemical_list: D015415:Biomarkers; D018797:Cell Cycle Proteins; D003037:Cobalt Radioisotopes; D017874:Immediate-Early Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C439070:GADD45A protein, human; D000097642:GADD45 Proteins; C118926:IER5 protein, human