Effect of lonizing Radiation on the Expression of p16,CyclinD1 and CDK4 in Mouse Thymocytes and Splenocytes

OBJECTIVE: To investigate the effect of ionizing radiation on the expression of p16, CyclinD1, and CDK4 in mouse thymocytes and splenocytes. METHODS: Fluorescent staining and flow cytometry analysis were employed for the measurement of protein expression. RESULTS: In time course experiments, it was found that the expression of p16 protein was significantly increased at 8, 24, and 48 h for thymocytes (P < 0.05, P < 0.01, and P < 0.05, respectively) and at 24 h for splenocytes (P < 0.05) after whole body irradiation (WBI) with 2.0 Gy X-rays. However, the expression of CDK4 protein was significantly decreased from 8 h to 24 h for thymocytes (P < 0.05-P < 0.01) and from 8 h to 72 h for splenocytes (P < 0.05-P < 0.01). In dose effect experiments, it was found that the expression of p16 protein in thymocytes and splenocytes was significantly increased at 24 h after WBI with 1.0, 2.0, and 4.0 Gy (P < 0.05-P < 0.01), whereas the expression of CDK4 protein was significantly decreased with 2.0 Gy for thymocytes (P < 0.05) and 0.5-6.0 Gy for splenocytes (P < 0.05-P < 0.01). Results also showed that the expression of CyclinD1 protein decreased markedly in both thymocytes and splenocytes after exposure. CONCLUSION: The results indicate that the expression of p16 protein in thymocytes and splenocytes can be induced by ionizing radiation, and the p16-CyclinD1/CDK4 pathway may play an important role for G1 arrest of thymocytes induced by X-rays.     

电离辐射诱导细胞周期解偶联的实验研究

目的　观察电离辐射能否诱导细胞周期解偶联。方法　采用PI荧光标记及流式细胞术 (FCM)测定细胞周期并分析细胞倍体的变化。结果　 1 0、2 0、4 0和 6 0GyX射线照射后 2 4h ,SKOV 3的二倍体细胞数明显减少 (分别为P <0 0 1) ,且呈现明显的剂量依赖性 ;而四倍体细胞数明显增加 (分别为P <0 0 1) ,亦呈现明显的剂量依赖性 ;与此同时 ,八倍体细胞数显著增高 (分别为P <0 0 1)。结论　电离辐射可诱导人卵巢癌SKOV 3细胞周期解偶联。     

X射线全身照射对小鼠骨髓细胞周期的影响

目的 研究不同剂量X射线全身照射对小鼠骨髓细胞周期的影响。方法 采用PI标记及流式细胞术（FCM）检测细胞周期的变化。结果 发现，1.0-6.0GyX射线线全身照射后12h，小鼠骨髓细胞G1及G2期明显增高，而S期明显减少；同时发现，0.05-0.2Gy低剂量X射线全身照射后72h,G1期骨髓细胞明显减少。而S期细胞明显增高。结论 0.5Gy以上剂量X射线全身照射可诱导小鼠骨髓细胞G1及G2期阻滞，使骨髓细胞增殖明显受抑；而0.2Gy以下低剂量照射则可刺激骨髓细胞增殖。     

Effect of Ionizing Radiation on the Expression of p16, CyclinDI and CDK4 in Mouse Thymocytes and Splenocytes

Objective To investigate the effect of ionizing radiation on the expression of p16, CyclinDl, and CDK4 in mouse thymocytes and splenocytes. Methods Fluorescent staining and flow cytometry analysis were employed for the measurement of protein expression. Results In time course experiments, it was found that the expression of p16 protein was significantly increased at 8, 24, and 48 h for thymocytes (P<0.05, P<0.01, and P<0.05, respectively) and at 24 h for splenocytes (P<0.05) after whole body irradiation (WBI) with 2.0 Gy X-rays. However, the expression of CDK4 protein was significantly decreased from 8 h to 24 h for thymocytes (P<0.05,P<0.01) and from 8 h to 72 h for splenocytes (P<0.05-P<0.01). In dose effect experiments, it was found that the expression of p16 protein in thymocytes and splenocytes was significantly increased at 24 h after WBI with 1.0, 2.0, and 4.0 Gy (P<0.05-P<0.01), whereas the expression of CDK4 protein was significantly decreased with 2.0Gy for thymocytes (P<0.05) and 0.5-6.0 Gy f     

精神分裂症与染色体22q11的连锁不平衡研究

目的 探讨染色体22q11泛有素融合降解1型蛋白基因(UFD1L)和腭心面综合征缺失的核定位信号基因(NLVCF)多态性与精神分裂症的关系。方法 在138例吉林省汉族精神分裂症患者及其健康父母双亲的核心家系中，以聚合酶链反应(PCR)和限制性片段长度多态(RFLP)方法对UFDlL基因rs1547931(G／C碱基改变)和NLVCF基因rs1473109(C／T碱基改变)单核苷酸多态性(SNPs)进行检测。应用基于家系的连锁不平衡方法，包括单体型相对风险分析(HRR)，传递不平衡检验(TDT)及Transmit双位点单体型分析，分析基因型数据。结果 (1)HRR显示UFDlL基因rs1547931与精神分裂症有关联(χ^2=4．260，ν=1，P=0．039)，NLVCF基因rs1473109与精神分裂症无关联；(2)TDT显示UFDlL基因rs1547931与精神分裂症有连锁和关联(χ^2=5．333，ν=1，P=0．021)，NLVCF基因rs1473109与精神分裂症无连锁及关联；(3)Transmit双位点单体型分析显示rs1547931-rs1473109单体型与精神分裂症有关联(χ^2=9．723，ν=3，P=0．021)，rs1547931(C)-rs1473109(T)单体型与精神分裂症呈负相关(χ^2=6．607，ν=1，P=0．01)。结论 精神分裂症患者UFD1L基因本身或其附近的基因可能与精神分裂症的易感性相关。