Synthesis of omega-3 long-chain polyunsaturated fatty acid-rich triacylglycerols in an endemic goby, Gymnogobius isaza, from Lake Biwa, Japan
Synthesis of omega-3 long-chain polyunsaturated fatty acid-rich triacylglycerols in an endemic goby, Gymnogobius isaza, from Lake Biwa, Japan
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日本琵琶湖特有虾虎鱼 Gymnogobius isaza 中富含 omega-3 长链多不饱和脂肪酸的三酰甘油的合成
DOI：
10.1093/jb/mvy035
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Umeda Masato
中科院分区：
文献类型：
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作者：
Suito Takuto;Nagao Kohjiro;Hatano Masataka;Kohashi Kenichi;Tanabe Aiko;Ozaki Hiromichi;Kawamoto Jun;Kurihara Tatsuo;Mioka Tetsuo;Tanaka Kazuma;Hara Yuji;Umeda Masato
通常观察到，淡水鱼含有的ω-3长链多不饱和脂肪酸（LC-PUFA），如二十碳五烯酸（EPA，C20：5 n-3）和二十二碳六烯酸（DHA，C22：6 n-3）的含量低于海洋鱼类。在这项研究中，我们进行了详细的比较分析的磷脂（PLs）和三酰甘油（TAG）的Gymnogobius isaza，一个淡水虾虎鱼特有的琵琶湖湖底栖息，和Gymnogobius urotaenia，一个相关的虾虎鱼栖息的海岸的琵琶湖。我们发现G. Isazacontain在PL和TAG中均具有显著高量的ω-3 LC-PUFA。TAG的质谱分析表明，最丰富的TAG分子种类是TAG（16：0/18：1/20：5），其次是TAG（14：0/18：1/20：5），其中EPA在n-1或sn-3位置并入TAG。我们从G.使用中性脂质缺陷酵母突变株的表达研究表明，GiDGAT 1和GiDGAT 2都具有二酰基甘油酰基转移酶活性，并且在GiDGAT 1存在下观察到LC-PUFA优先掺入TAG。本研究揭示了G. isazaand鉴定了参与含PUFA的TAG的产生的酶。
It is commonly observed that freshwater fish contain lower amounts of omega-3 long-chain polyunsaturated fatty acids (LC-PUFAs), such as eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3), than marine fish species. In this study, we performed a detailed comparative analysis of phospholipids (PLs) and triacylglycerols (TAGs) fromGymnogobius isaza, a freshwater goby endemic to Lake Biwa inhabiting the lake bottom, andGymnogobius urotaenia, a related goby that inhabits the shore of Lake Biwa. We found that tissues fromG. isazacontain remarkably high amounts of omega-3 LC-PUFAs in both PLs and TAGs. Mass spectrometry analysis of TAGs demonstrated that the most abundant TAG molecular species were TAG (16:0/18:1/20:5), followed by TAG (14:0/18:1/20:5), in which EPA is incorporated into TAG at either thesn-1 orsn-3 positions. We isolated cDNAs encoding acyl-CoA: diacylglycerol acyltransferase designated asGiDGAT1 andGiDGAT2, fromG. isaza.Expression studies using a neutral lipid-deficientSaccharomyces cerevisiaemutant strain demonstrated that bothGiDGAT1 andGiDGAT2 possessed diacylglycerol acyltransferase activity, and preferential incorporation of LC-PUFA into TAG was observed in the presence ofGiDGAT1. This study revealed the novel lipid profiles ofG. isazaand identified the enzymes that were involved in the production of PUFA-containing TAGs.