Kim Tae Im, Cho Pyo Yun, Song Kwang Jin, Li Shunyu, Hong Sung-Jong, Park Suk Won, Chai Jong-Yil, Shin Eun-Hee
Department of Parasitology, Chung-Ang University College of Medicine, Tongjak-gu, Seoul 156-756, Korea.
Parasitol Res. 2008 May;102(6):1143-50. doi: 10.1007/s00436-008-0882-y. Epub 2008 Jan 27.
Gamma-rays are a form of ionizing radiation and produce serious cellular damage to nuclei and organelles. Gamma irradiation induces the expressions of genes involved in DNA repair. Clonorchis sinensis resides in and provokes pathophysiologic changes in the bile ducts of mammals. The C. sinensis metacercariae are unsusceptible or resistant to gamma irradiation with LD50 of 16.5 Gy. Using the annealing control primer-based polymerase chain reaction (PCR) method, 19 genes were found to be up-regulated in C. sinensis metacercariae exposed to gamma rays. Contigs of up-regulated genes (URGs) were retrieved in a C. sinensis expressed sequence tag pool and extended by DNA-walking. Of the 13 URGs annotated putatively as functional genes, five URGs were associated with energy metabolism, six with protein processing, and the other two with DNA repair protein RAD23 and inhibitor of apoptosis protein. Four URGs were confirmed up-regulated by gamma irradiation by quantitative real-time PCR. One unknown gene, which was up-regulated to the greatest extent, might contribute to early recovery from gamma-irradiation-induced damage. The up-regulations of genes encoding DNA repair, protein processing, and energy metabolism proteins suggests that increases in gene products orchestrate DNA lesion repair and recover cellular functions in gamma-irradiated C. sinensis metacercariae.
γ射线是一种电离辐射形式，会对细胞核和细胞器造成严重的细胞损伤。γ辐射可诱导参与DNA修复的基因表达。华支睾吸虫寄生于哺乳动物胆管并引发病理生理变化。华支睾吸虫囊蚴对γ辐射不敏感或具有抗性，其半数致死剂量为16.5 Gy。采用基于退火控制引物的聚合酶链反应（PCR）方法，发现19个基因在受到γ射线照射的华支睾吸虫囊蚴中上调。上调基因（URGs）的重叠群在华支睾吸虫表达序列标签库中检索到，并通过DNA步移进行延伸。在13个被推测注释为功能基因的URGs中，5个URGs与能量代谢相关，6个与蛋白质加工相关，另外2个与DNA修复蛋白RAD23和凋亡抑制蛋白相关。通过定量实时PCR证实4个URGs因γ辐射而上调。一个上调程度最大的未知基因可能有助于从γ辐射诱导的损伤中早期恢复。编码DNA修复、蛋白质加工和能量代谢蛋白的基因上调表明，基因产物的增加协调了γ辐射的华支睾吸虫囊蚴中的DNA损伤修复并恢复细胞功能。
