Cytochrome P450 1A (Cyp1a) catabolizes polycyclic organic compounds. In this study, we sequenced the cyp1a gene from two Javanese medaka Oryzias javanicus strains and examined gene expression in response to two organic pollutants, phenanthrene and pyrene. Sequence comparisons among the two strains identified several single-nucleotide polymorphisms (SNPs), two of which resulted in amino acid substitutions. Reverse transcription PCR analysis of major organs revealed that the cyp1a mRNA level is highest in the liver. After determining LC50s against phenanthrene and pyrene for 96 h (3.9 and 2.5 µM, respectively), cyp1a mRNA expression in the liver against sublethal concentrations of phenanthrene and pyrene was examined. Using quantitative real-time PCR, a positive correlation was discovered between the cyp1a mRNA levels and pyrene concentration, and similar tendency was observed for phenanthrene. cyp1a may serve as a quantitative indicator of a broad range of pollutants.

中文翻译：

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爪哇鳉中细胞色素 P450 1A (cyp1a) mRNA 表达与环境菲和芘浓度的相关性

细胞色素 P450 1A (Cyp1a) 分解代谢多环有机化合物。在这项研究中，我们对来自两个爪哇青鳉的 cyp1a 基因进行了测序，并检查了响应两种有机污染物菲和芘的基因表达。两个菌株之间的序列比较确定了几个单核苷酸多态性 (SNP)，其中两个导致氨基酸取代。主要器官的逆转录 PCR 分析显示 cyp1a mRNA 水平在肝脏中最高。在确定针对菲和芘的 LC50s 96 小时（分别为 3.9 和 2.5 µM）后，检测了肝脏中针对亚致死浓度菲和芘的 cyp1a mRNA 表达。使用实时定量 PCR，发现 cyp1a mRNA 水平与芘浓度之间呈正相关，对菲也观察到类似的趋势。cyp1a 可作为多种污染物的定量指标。