60Co γ射线急性照射对比格犬外周血淋巴细胞基因表达谱的影响

Alteration of gene expression profile in Beagle dogs＇ peripheral blood lymphocytes after acute γ-rayirradiation

目的 探讨急性照射后比格犬外周血淋巴细胞基因表达谱的变化。方法 将20只雄性成年比格犬用单纯随机数字表法均衡分为4组：空白对照组和0.5、2.0、5.0 Gy 3个照射组，60Co γ射线急性照射相应剂量，照后6 h采集外周血，分离淋巴细胞进行总RNA提取和基因芯片杂交以开展差异表达基因筛选，并对差异表达基因进行基因本体（GO）分析，以及京都基因与基因组百科数据库（KEGG）通路分析，以实时定量PCR（qRT-PCR）进行结果验证。结果 与空白对照组相比，3个剂量组受照后6 h共有308条基因差异表达2倍以上，其中61条表达上调，247条表达下调，主要涉及免疫反应、肿瘤发生等。共同差异表达基因的GO富集分析涉及细胞连接、信号转导、氧化还原及物质代谢等，共同涉及的KEGG通路包含肿瘤途径、p53信号通路和JAK-STAT信号通路、酪氨酸代谢等。通过qRT-PCR验证，凋亡增强核酸酶（AEN）和促分裂原活化蛋白激酶13（MAP3K13）基因表达结果与基因芯片结果一致。结论 不同剂量的γ射线急性照射均对比格犬外周血淋巴细胞的基因表达谱产生明显影响，共同差异表达基因涉及免疫系统、物质代谢及致癌效应等多项生物学功能及相关通路。

Objective To investigate the changes of gene expression profile in Beagle dogs＇ peripheral blood lymphocytes after acute irradiation.Methods Totally 20 male adult Beagle dogs were randomly divided into four groups including non-treatment blank control group and three radiation groups exposed to 0.5, 2.0, and 5.0 Gy of γ-rays, respectively. Six hours after radiation, the peripheral blood were collected for lymphocytes isolation. Total RNA was extracted from the lymphocytes and analyzed by microarray hybridization. The differential gene profiles of radiation groups were analyzed by gene ontology （GO） analysis and kyoto encyclopedia of genes and genomes （KEGG） pathways analysis, and the alerted genes were further confirmed by the real time quantitative PCR （qRT-PCR） assay. Results Compared to the blank control group, the expressions of 308 genes in the radiation groups were perturbed over 2-fold of control, including 61 genes up-regulated and 247 genes down-regulated, which were mainly associated with immune response and cancer occurrence. The GO analysis indicated that the differential expressed genes were associated with cell connection, signal transduction, oxidation-reduction reaction and metabolism. The KEGG pathway analysis showed that some physiological and biochemical processes were involved, such as phagocytosis, tumor pathway, p53 signaling pathway, JAK-STAT signal pathway, cell differentiation, and proliferation, oxidative phosphorylation, glycogen dysplasia and other pathways. The microarray data of the alterations of apoptosis enhancing nuclease（AEN） and mitogenactivated protein kinase 13（MAP3K13） gene expressions were further confirmed by qRT-PCR. Conclusions Exposure to different doses of acute γ-ray irradiation had significant impact on the gene expressions in Beagle dogs＇ peripheral blood lymphocytes and those differential expressed genes were related to a series of biological processes and pathways including immune response, metabolism and carcinogenesis.