The Nrf2 molecule trigger antioxidant defense against acute benzo(a)pyrene exposure in the thick shell mussel Mytilus coruscus
The Nrf2 molecule trigger antioxidant defense against acute benzo(a)pyrene exposure in the thick shell mussel Mytilus coruscus
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DOI：
10.1016/j.aquatox.2020.105554
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发表时间：
2020-09-01
影响因子：
4.5
通讯作者：
Tang, Zurong
中科院分区：
文献类型：
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作者：
Qi, Pengzhi;Tang, Zurong
NF-E2相关因子2（Nrf 2）是一种普遍存在的、进化上保守的转录因子，是细胞中氧化应激的主要传感器。在本研究中，一个新的Nrf 2同源物中鉴定厚壳贻贝厚壳贻贝。因此，它的功能作用，在抗氧化防御响应急性苯并（a）芘（Bap）暴露进行了评估。通过Blast、多重序列比对和系统发育分析，新发现的McNrf 2属于传统的Nrf 2家族。Bap急性暴露后，鳃和消化腺中的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）和谷胱甘肽还原酶（GR）等抗氧化酶在mRNA和酶水平上均受到显著诱导，McNrf 2 mRNA的表达也显著上调。McNrf 2的表达与这些抗氧化基因的mRNA水平相关的分析显示出正相关，表明Nrf 2是这些基因长期诱导所必需的。进一步通过pET-32a原核表达系统获得重组McNrf 2。在50 μ g/L Bap暴露后，与Nrf 2野生型贻贝相比，Nrf 2过表达贻贝鳃中的ROS产生和LPO水平显著降低，消化腺中的ROS产生也减少。总的来说，这些结果表明，Nrf 2途径可以提供保护，从Bap引发的氧化应激在厚壳贻贝。
The NF-E2-related factor 2 (Nrf2), an ubiquitous, evolutionarily conserved transcription factor, acts as a major sensor of oxidative stress in cells. In the present study, a Nrf2 homolog was newly identified in the thick shell mussel Mytilus coruscus. Accordingly, its functional role in antioxidant defense in response to acute benzo(a) pyrene (Bap) exposure was assessed. The newly identified McNrf2 affiliated to traditional Nrf2 family through Blast, multiple alignment and phylogenetic analysis. After acute exposure to Bap, antioxidants including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathine reductase (GR) were significantly induced in gills and digestive glands at both mRNA and enzymatic levels, and the expression of McNrf2 mRNA was also up-regulated. The analysis of correlating the expression of McNrf2 and the mRNA levels of these antioxidant genes showed positive ties, indicating that Nrf2 was needed for protracted induction of such genes. Further, the recombinant McNrf2 was produced through pET-32a prokaryotic system. After 50 mu g/L Bap exposure, ROS generation and LPO level in gills of Nrf2 over-expressed mussels significantly decreased compared to Nrf2 wild-type mussels, as well as reduced ROS production in digestive glands. Collectively, these results show that Nrf2 pathway can provide protection from oxidative stress triggered by Bap in the thick shell mussel.