Transcription-coupled repair pathway in UVC-induced SupF gene mutation in Tet-on 293 cell line

Objective： To explore the role of transcription-coupled repair （TCR） pathway in the UVC-induced SupF gene mutation in Tet-on 293 cell line, we designed and constructed a Tet-responsive plasmid DNA pTCR-C1, and utilized this pTCR-C 1 plasmid to obtain the mutation frequency of SupF reporter gene induced by UVC in Tet-on 293 cell line. Methods： SupF gene was cloned into a Tet-responsive plamid pBI-L, which include a bidirectional Tet-responsive promoter, and was named pTCR-C1. The pTCR-C1 plasmid was transfected into Tet-on 293 cell line, and the mutation frequency of SupF reporter gene was detected in the presence and absence of DOX. Results： The pTCR-C1 plasmid was identified with the methods of restriction digestion and DNA sequencing. The mutation frequency of SupF reporter gene in the presence of DOX was higher than in the absence of DOX. Conclusion： The TCR pathway takes part in the UVC-induced SupF gene mutation in Tet-on 293 cell line.

lncRNA PACER促进脓毒症急性肺损伤炎症反应的实验研究

目的探讨lncRNA PACER对小鼠脓毒症急性肺损伤炎症反应的促进作用。方法分离和培养急性肺损伤和健康非吸烟者的肺泡巨噬细胞,以及获取细菌脂多糖(LPS)诱导的急性肺损伤(ALI)小鼠肺组织,采用qRT-PCR方法检测lncRNA PACER的表达;过表达或敲低PACER后,ELISA方法检测THP-1和RAW264.7细胞炎性因子肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)的表达;对LPS所致ALI小鼠,尾静脉注射PACER siRNA慢病毒后,ELISA检测小鼠血清炎性因子TNF-α、IL-6的表达,HE染色观察肺组织病理学变化。结果 ALI患者肺泡巨噬细胞和ALI小鼠肺组织中lncRNA PACER表达均显著升高(P<0.01);细胞过表达PACER后,细胞炎性因子肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)的表达升高,而敲低PACER后,炎性因子TNF-α、IL-6的表达则降低(P<0.01); ALI小鼠敲低PACER后,小鼠肺组织和血清中炎性因子TNF-α、IL-6的表达均显著降低(P<0.01),肺组织损伤程度明显减弱。结论 lncRNA PACER可显著促进脓毒症急性肺损伤炎症反应,为明确lncRNA PACER作为ALI防治的靶标提供了依据。