Molecular cloning, characterization, and expression of an omega-3 fatty acid desaturase gene from Sapium sebiferum.
A full-length cDNA (SsFAD3) for an omega-3 fatty acid desaturase (omega-3 FAD) was cloned from Sapium sebiferum (L.) Roxb. using rapid amplification of cDNA ends and reverse transcription polymerase chain reaction methods. SsFAD3 contained a 1119-bp open reading frame encoding a 372-amino acid polypeptide. The genomic sequence region of the SsFAD3 ORF was composed of 8 exons and 7 introns, similar to other omega-3 FADs found in most plants. The amino acid sequence showed a higher identity with microsomal omega-3 FADs than plastidial omega-3 FADs. Southern blot analysis of SsFAD3 suggested the existence of a small gene family composed of several copies or closely linked genes. SsFAD3 transcripts were detected in shoots, roots, leaves, stems, and seeds, but were most abundant in shoots. The function of SsFAD3 was confirmed by the accumulation of alpha-linolenic acid (alpha-18:3) in Saccharomyces cerevisiae transformants.
Niu
Bei
B
College of Life Science, Sichuan University, Chengdu 610064, PR China.
Guo
Liang
L
Zhao
Mingming
M
Luo
Tong
T
Zhang
Rong
R
Zhang
Fuli
F
Hou
Pei
P
Zhang
Ying
Y
Xu
Ying
Y
Wang
Shenghua
S
Chen
Fang
F
D001483:Base Sequence; D001709:Biotechnology / Q000379:methods*; D015139:Blotting, Southern; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D018076:DNA, Complementary / Q000737:chemistry; D005091:Exons; D044943:Fatty Acid Desaturases / Q000737:chemistry* / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D007438:Introns; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D012333:RNA, Messenger / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics*; D031287:Sapium / Q000201:enzymology*
D017931:DNA Primers; D018076:DNA, Complementary; D012333:RNA, Messenger; D044943:Fatty Acid Desaturases; C078565:omega-3 fatty acid desaturase