[The synthesis and function analysis of omega-3 fatty acid desaturase gene from Caenorhabditis briggssae].
Omega-3 polyunsaturated fatty acids (PUFAs) have been broadly investigated and shown to exert many preventive and therapeutic actions besides their important role in maintenances human health and normal development. In mammals, the level of omega-3 PUFAs is relatively too low compared with omega-6 PUFAs, which metabolically and functionally distinct from omega-3 PUFAs and often have important opposing physiological functions. Either the inefficiency of omega-3 PUFAs or the excess of omega-6 PUFAs will cause many healthy problems. So methods have been sought to increase the amount of omega-3 PUFAs and to improve the omega-6/omega-3 ratio in body. In this study, the sFat-1 gene, which putatively encodes a omega-3 fatty acid desaturase, was chemically synthesized according to the sequence from Caenorhabditis briggssae (with codon usage modified), and constructed into a mammal expression vector pcDNA3. 1-sFat1-EGFP. This vector was introduced into CHO cells by lipid-mediated transfection, and it's expression quickly and effectively elevated the cellular omega-3 PUFAs (from 18-carbon to 22-carbon) contents and dramatically improved the ratio of omega-6/omega-3 PUFAs. Cellular lipids extracts from stably selected cells were analyzed with GC-MS and the results showed that amount of total omega-6 PUFAs dropped from 48.97% (in GFP cells)to 35.29% (in sFat-1 cells), whereas the amount of total omega-3 PUFAs increased from 7.86% to 24.02%, respectively. The omega-6/omega-3 ratio also dropped from 6.23 to 1.47. These data demonstrates the Caenorhabditis briggssae omega-3 Fatty Acid Desaturase gene, sFat-1, was synthesized successfully and can produce omega-3 PUFAs by using the corresponding omega-6 PUFAs as substrates, which shows its potential for use in the production of omega-3 PUFAs in transgenic animals.
Zhu
Gui-Ming
GM
Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China.
Chen
Hong
H
Zhou
Yan-Rong
YR
Lu
Jian-Shen
JS
Wu
Xiao-Jie
XJ
Chen
Hong-Xing
HX
Deng
Ji-Xian
JX
D000818:Animals; D016466:CHO Cells; D002107:Caenorhabditis / Q000201:enzymology / Q000235:genetics*; D006224:Cricetinae; D003412:Cricetulus; D044943:Fatty Acid Desaturases / Q000235:genetics* / Q000502:physiology; D005227:Fatty Acids / Q000032:analysis; D010957:Plasmids; D016133:Polymerase Chain Reaction
D005227:Fatty Acids; D044943:Fatty Acid Desaturases; C078565:omega-3 fatty acid desaturase