title: Cloning and characterization of a β-ketoacyl-acyl carrier protein synthase II from Jatropha curcas.
abstract: A cDNA clone encoding a putative β-ketoacyl-acyl carrier protein (ACP) synthase II (KASII), a key enzyme in fatty acid biosynthesis, was isolated from Jatropha curcas L., a woody oil plant. The isolated cDNA clone of JcKASII contained a 1722-bp open reading frame coding for 573 amino acids with a predicted molecular mass of about 60.98 kDa and the conserved Cys(324) residues that has been proposed as the active site of KASII proteins. The deduced amino acid sequence of the cDNA clone had about 70-84% identity with the KASII from other plants. The transcript of JcKASII was detected in all tissues examined and increased during seed maturation. Expression of JcKASII in the Arabidopsis KASII mutant (fab1) could complement the fatty acid composition of the mutant. Overexpression of JcKASII cDNA under the cauliflower mosaic virus 35S promoter in Arabidopsis resulted in decreasing 16-carbon fatty acids and increasing 18-carbon fatty acids in leaves and seeds. Taken together, these results show that JcKASII could function in 18-carbon fatty acids accumulation in plant and may be useful in the genetic engineering of J. curcas.
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wei
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Pingzhi
authors.initials: P
authors.lastname: Wu
authors.forename: Yaping
authors.initials: Y
authors.lastname: Chen
authors.forename: Meiru
authors.initials: M
authors.lastname: Li
authors.forename: Huawu
authors.initials: H
authors.lastname: Jiang
authors.forename: Guojiang
authors.initials: G
authors.lastname: Wu
mesh_terms: D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase / Q000737:chemistry* / Q000235:genetics*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D002681:China; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005227:Fatty Acids / Q000096:biosynthesis / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D031286:Jatropha / Q000201:enzymology* / Q000235:genetics*; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000737:chemistry / Q000235:genetics; D030821:Plants, Genetically Modified; D012639:Seeds / Q000737:chemistry / Q000254:growth & development; D017386:Sequence Homology, Amino Acid
chemical_list: D018076:DNA, Complementary; D005227:Fatty Acids; D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase