Identification and characterization of a delta-12 fatty acid desaturase gene from marine microalgae Isochrysis galbana  

作　　者：Xiaotian Han Shuai Wang Li Zheng Wanshun Liu 

机构地区：[1]College of Marine Life Sciences,Ocean University of China [2]Changjiang Estuary Marine Ecosystem Research Station,Institute of Oceanology,Chinese Academy of Sciences [3]Marine Ecology and Environmental Science Laboratory,Pilot National Laboratory for Marine Science and Technology (Qingdao) [4]Key Laboratory for Marine Bioactive Substances and Modern Analytical Technology,First Institute of Oceanography,Ministry of Natural Resources

出　　处：《Acta Oceanologica Sinica》2019年第2期107-113,共7页海洋学报（英文版）

基　　金：The Basic Scientific Fund for National Public Research Institutes of China under contract No.2017Q09;the Aoshan Science and Technology Innovation Project of Pilot National Laboratory for Marine Science and Technology(Qingdao)under contract No.2016ASKJ02;the National Natural Science Foundation of China-Shandong Joint Funded Project under contract No.U1606404;the National Natural Science Foundation of China under contract Nos 41776176 and 41806201;the 973 Project from Chinese Ministry of Science and Technology under contract No.2015CB755904;the Shandong Provincial Natural Science Foundation under contract No.ZR2015PD003

摘　　要：The cDNA of the delta-12 fatty acid desaturase gene, IgFAD2, was cloned from the marine microalgae Isochrysis galbana, a species capable of producing docosahexaenoic acid. Sequence analysis indicated that the open reading frame measured a length of 1 158 bp and encoded 386 amino acids with a predicted molecular weight of 42.8 kDa and an isoelectric point of 9.2. Computational analysis of the protein sequence of IgFAD2 showed typical features of membrane-bound desaturase such as three conserved histidine boxes along with four membranespanning regions that were universally present among plant desaturases. Quantitative real-time PCR results showed that the abundance of IgFAD2 transcript was significantly upregulated under different environmental stresses including low temperature(15℃), high salinity(salinity of 62 and 93), and nitrogen starvation(220 μmol/L). Heterologous expression indicated that yeast cells transformed with a plasmid construct containing IgFAD2 could convert endogenous oleic acid(18:1^(?9), OA) into linoleic acid(18:2^(?9, 12), LA). These findings confirm that I. galbana IgFAD2 plays important roles in the biosynthetic pathways of unsaturated fatty acids.The cDNA of the delta-12 fatty acid desaturase gene, IgFAD2, was cloned from the marine microalgae Isochrysis galbana, a species capable of producing docosahexaenoic acid. Sequence analysis indicated that the open reading frame measured a length of 1 158 bp and encoded 386 amino acids with a predicted molecular weight of 42.8 kDa and an isoelectric point of 9.2. Computational analysis of the protein sequence of IgFAD2 showed typical features of membrane-bound desaturase such as three conserved histidine boxes along with four membranespanning regions that were universally present among plant desaturases. Quantitative real-time PCR results showed that the abundance of IgFAD2 transcript was significantly upregulated under different environmental stresses including low temperature(15℃), high salinity(salinity of 62 and 93), and nitrogen starvation(220 μmol/L). Heterologous expression indicated that yeast cells transformed with a plasmid construct containing IgFAD2 could convert endogenous oleic acid(18:1^(?9), OA) into linoleic acid(18:2^(?9, 12), LA). These findings confirm that I. galbana IgFAD2 plays important roles in the biosynthetic pathways of unsaturated fatty acids.

关 键 词：delta-12 FATTY ACID DESATURASE expression analysis ISOCHRYSIS GALBANA 

分 类 号：P[天文地球]