Donghu Experimental Station of Lake Ecosystems, State Key Laboratory for Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China.
Donghu Experimental Station of Lake Ecosystems, State Key Laboratory for Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China.
Ecotoxicol Environ Saf. 2012 May;79:206-213. doi: 10.1016/j.ecoenv.2012.01.001. Epub 2012 Jan 20.
Microcystin-LR (MCLR) is a widespread cyanotoxin, which can influence genes transcription and cause nucleic acid damage in different organisms. To identify MCLR induced transcriptionally changed hepatic genes in bighead carp by subtractive suppression hybridization, we obtained the cDNA fragment of cda. Then we cloned its full-length cDNA, which encodes a cytidine deaminase (CDA). 3D structure prediction showed that the 3D structure and amino acid residues related to function sites of bighead carp CDA were highly conserved. Bighead carp CDA shared high identities with other CDA sequences, and evolved closely to non-mammalian CDAs. Bighead carp expressed cda in all tested tissues under normal situation, and changed its expression profile in a time inversely dependent and dose dependent manner to MCLR, so as to protect itself from MCLR induced toxic damage. These indicated that cda might be involved in anti-MCLR response, especially in the regulation of cytidine and dexocytidine metabolism pathway.
微囊藻毒素-LR（MCLR）是一种广泛存在的蓝藻毒素，它可以影响不同生物体的基因转录，并导致核酸损伤。为了通过消减抑制杂交鉴定大头鱼肝脏中受 MCLR 诱导的转录变化基因，我们获得了 cda 的 cDNA 片段。然后我们克隆了其全长 cDNA，它编码胞苷脱氨酶（CDA）。3D 结构预测表明，大头鱼 CDA 的 3D 结构和与功能位点相关的氨基酸残基高度保守。大头鱼 CDA 与其他 CDA 序列具有很高的同一性，并与非哺乳动物 CDAs 密切进化。在正常情况下，大头鱼在所有测试的组织中都表达 cda，并以时间和剂量依赖的方式改变其表达谱，以保护自身免受 MCLR 诱导的毒性损伤。这表明 cda 可能参与抗 MCLR 反应，特别是在胞苷和去胞苷代谢途径的调节中。
