http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
THE SHORT‐TERM EFFECTS OF LOW‐DOSE‐RATE RADIATION ON EL4 LYMPHOMA CELL
봉진종,강유미,신석철,최무현,최승진,이경미,김희선 대한방사선방어학회 2012 방사선방어학회지 Vol.37 No.2
To determine the biological effects of low‐dose‐rate radiation (137Cs, 2.95 mGy/h) on EL4 lymphoma cells during 24 h, we investigated the expression of genes related to apoptosis, cell cycle arrest, DNA repair, iron transport, and ribonucleotide reductase. EL4 cells were continuously exposed to low‐dose‐rate radiation (total dose: 70.8 mGy) for 24 h. We analyzed cell proliferation and apoptosis by trypan blue exclusion and flow cytometry, gene expression by real‐time PCR, and protein levels with the apoptosis ELISA kit. Apoptosis increased in the low‐dose‐rate irradiated cells, but cell number did not differ between non‐ (Non‐IR) and low‐dose‐rate irradiated (LDR‐IR) cells. In concordance with apoptotic rate, the transcriptional activity of ATM, p53, p21, and Parp was upregulated in the LDR‐IR cells. Similarly, Phospho‐p53 (Ser15), cleaved caspase 3 (Asp175), and cleaved Parp (Asp214) expression was upregulated in the LDR‐IR cells. No difference was observed in the mRNA expression of DNA repair‐related genes (Msh2, Msh3, Wrn, Lig4, Neil3, ERCC8, and ERCC6) between Non‐IR and LDR‐IR cells. Interestingly, the mRNA of Trfc was upregulated in the LDR‐IR cells. Therefore, we suggest that short‐term low‐dose‐rate radiation activates apoptosis in EL4 lymphoma cells.
Differential expression of thymic DNA repair genes in low-dose-rate irradiated AKR/J mice
봉진종,강유미,신석철,최승진,이경미,김희선 대한수의학회 2013 Journal of Veterinary Science Vol.14 No.3
We previously determined that AKR/J mice housed in a low-dose-rate (LDR) (137Cs, 0.7 mGy/h, 2.1 Gy) γ-irradiation facility developed less spontaneous thymic lymphoma and survived longer than those receiving sham or high-dose-rate (HDR) (137Cs, 0.8 Gy/min, 4.5 Gy) radiation. Interestingly,histopathological analysis showed a mild lymphomagenesis in the thymus of LDR-irradiated mice. Therefore, in this study, we investigated whether LDR irradiation could trigger the expression of thymic genes involved in the DNA repair process of AKR/J mice. The enrichment analysis of Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways showed immune response, nucleosome organization,and the peroxisome proliferator-activated receptors signaling pathway in LDR-irradiated mice. Our microarray analysis and quantitative polymerase chain reaction data demonstrated that mRNA levels of Lig4 and RRM2 were specifically elevated in AKR/J mice at 130 days after the start of LDR irradiation. Furthermore, transcriptional levels of H2AX and ATM,proteins known to recruit DNA repair factors, were also shown to be upregulated. These data suggest that LDR irradiation could trigger specific induction of DNA repair-associated genes in an attempt to repair damaged DNA during tumor progression, which in turn contributed to the decreased incidence of lymphoma and increased survival. Overall, we identified specific DNA repair genes in LDR-irradiated AKR/J mice.
Expression Profiles of Apoptosis Genes in Mammary Epithelial Cells
백명기,Myung Bok Seol,봉진종 한국분자세포생물학회 2005 Molecules and cells Vol.20 No.1
To investigate apoptosis in HC11 mammary epithelial cells, we compared the gene expression profiles of actively growing and serum-starved apoptotic cells using a mouse apoptosis gene array and 33P-labeled cDNA prepared from the RNA of the two cultures. Analysis of the arrays showed that expression of several genes such as clusterin, secreted frizzled related protein mRNA (sFRP-1), CREB-binding protein (CBP), and others was higher in the apoptotic cells whereas expression of certain genes including survivin, cell division cycle 2 homolog A (CDC2), and cyclin A was lower. These expression patterns were confirmed by RT-PCR and/or Northern analyses. We compared the expression of some of these genes in the mouse mammary gland under various physiological conditions. The expression levels of genes (clusterin, CBP, and M6P-R) up-regulated in apoptotic conditions were higher at involution than during lactation. On the other hand, genes (Pin, CDC2) downregulated in apoptotic conditions were relatively highly expressed in virgin and pregnant mice. We conclude that certain genes such as clusterin, sFRP-1, GAS1 and CBP are induced in apoptotic mammary epithelial cells, and others are repressed. Moreover, the apoptosis array is an efficient technique for comparing gene expression profiles in different states of the same cell type.