Investigation of P53, HIPK-2 and EIF2S1 Genes Expression Changes Induced by in Vitro Gamma Radiation

Abstract

In this study, we have investigated induction of P53, HIPK-2 and EIF2S1 genes after exposure to low doses gam- ma radiation by using the peripheral human lymphocytes. Gene expression changes were analyzed in quanti- tative real time polymerase chain reaction QRT PCR by using B2M as a reference gene. Whole blood samples of ten young, healthy and non-smoking donors were taken. All samples were divided in to five specimens and four of them were irradiated using constant gamma irradiation source 60Co giving the dose rate of 0.0327 kGy/h while one sample used as control. Blood samples were exposed to 0.1 Gy, 0.5 Gy, 1 Gy and 3 Gy γ-rays. Results were expressed in terms of the threshold cycle value Ct in REST 2009 Relative Expression Software Tool V. 2.0.13 program and the difference between the CT values of the target gene and the reference gene was calculated. We found a linear dose–response relationship for P53, HIPK-2 and EIF2S1 genes. Results of the QRT PCR showed that three of the genes were up-regulated after radiation exposure. We concluded that P53, HIPK-2 and EIF2S1 genes can be promising for the assessment of gene expression changes in radiation expo- sure induced DNA damage.

Keywords

• Gene expression,Ionizing radiation,QRT PCR

İn Vitro Olarak Gama Radyasyon ile İndüklenen P53, HIPK-2 ve EIF2S1 Genlerinin Ekspresyon Değişikliklerinin Araştırılması

Abstract

B u çalışmada periferal insan lenfositlerinde düşük doz gama radyasyon maruziyeti sonrası P53, HIPK-2 ve EIF2S1 genlerinin indüksiyonunu araştırılmıştır. Gen ekspresyon değişiklikleri, B2M referans gen olarak kullanılarak kantitafif gerçek zamanlı polimeraz zincir reaksiyonu ile KRT PZR değerlendirilmiştir. Bu amaçla genç, sağlıklı ve sigara içmeyen on bireye ait kan örnekleri toplanmıştır. Her birey için beş tüpe bölünen örneklerden ilki kontrol olarak ayrılmış diğer dördü sabit gama kaynağında Co60 0,0327 kGy/sa doz hızına göre hesaplanmış 0,1 Gy, 0.5 Gy, 1 Gy ve 3 Gy gama radyasyonuna maruz bırakılmıştır. Sonuçlar eşik değerinin aşıldığı döngü değerlerine CT göre REST 2009 Relative Expression Software Tool V. 2.0.13 programında değerlendirilmiş, hedef genin ve referans genin CT değerleri arasındaki farklılıklara göre hesaplanmıştır. P53, HIPK2 ve EIF2S1 genleri için linear bir doz-cevap ilişkisi bulunmuştur. KRT PZR sonuçları bu üç geninin maruz kalınan dozlarda up-regüle olduğunu göstermiştir. Elde edilen sonuçlar P53, HIPK2 ve EIF2S1 genlerinin radyasyon maruziyeti sonrasında indüklenen DNA hasarında ki gen ekspresyon değişikliklerinin değerlendirilmesinde kullanılabileceğini göstermiştir

Keywords

• Gene ekspresyonu,iyonize radyasyon,QRT PCR

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