Xie Shaolin, Zhou Aiguo, Feng Yongyong, Zhang Yue, Li Junyi, Sun Zhuolin, Fan Lanfen, Zou Jixing
College of Marine Science, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China.
Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, People's Republic of China.
Biochem Genet. 2020 Aug;58(4):551-565. doi: 10.1007/s10528-020-09955-0. Epub 2020 Jun 5.
Cytochrome P4501A (CYP1A) has been used as a specific biomarker for monitoring water contamination such as PAHs, PCBs and dioxins. In the present study, the cyp1a gene of Gambusia affinis was cloned and sequenced and their expressions under PAHs exposure were characterized. The newly identified cyp1a encodes a protein with 521 amino acids that shared 96-80% identity with other Cyprinodontiformes fishes. RT-PCR analysis revealed that the basal mRNA level of cyp1a was highly expressed in liver and intestine. The expression level of cyp1a was significantly induced by exposure to 100 μg/L 3, 4-Benzopyrene (BaP) for 5 days in the muscle, testis, brain, liver and intestine of adult male fish. Except in the testis, the induced mRNA level of cyp1a ultimately decreased after prolonging the exposure time to 25 days. As for testis, the induced mRNA level of cyp1a was maintained at a high level during the entire exposure time under 100 μg/L BaP exposure. Furthermore, the expression of cyp1a increased with exposure time under a relatively low exposure concentrations 1 μg/L. Regarding the effects of other PAHs, D(a,h)A, BbF, and BaA showed a statistically significant effect of induction on mRNA level of cyp1a in the muscle, testis, brain, liver and intestine.
细胞色素P4501A（CYP1A）已被用作监测多环芳烃、多氯联苯和二恶英等水污染的特异性生物标志物。在本研究中，克隆并测序了食蚊鱼的cyp1a基因，并对其在多环芳烃暴露下的表达进行了表征。新鉴定的cyp1a编码一种含有521个氨基酸的蛋白质，与其他鲤齿目鱼类具有96%-80%的同一性。逆转录聚合酶链反应（RT-PCR）分析显示，cyp1a的基础mRNA水平在肝脏和肠道中高度表达。成年雄鱼的肌肉、睾丸、脑、肝脏和肠道暴露于100μg/L苯并[a]芘（BaP）5天后，cyp1a的表达水平显著诱导。除睾丸外，延长暴露时间至25天后，cyp1a的诱导mRNA水平最终下降。对于睾丸，在100μg/L BaP暴露下，整个暴露期间cyp1a的诱导mRNA水平维持在高水平。此外，在相对低的暴露浓度1μg/L下，cyp1a的表达随暴露时间增加。关于其他多环芳烃的影响，二苯并[a,h]蒽、苯并[b]荧蒽和苯并[a]蒽对肌肉、睾丸、脑、肝脏和肠道中cyp1a的mRNA水平显示出统计学上显著的诱导作用。
