title: Isolation and characterization of CCoAOMT in interspecific hybrid of Acacia auriculiformis x Acacia mangium--a key gene in lignin biosynthesis.
abstract: This study was directed at the understanding of the function of CCoAOMT isolated from Acacia auriculiformis x Acacia mangium. Full length cDNA of the Acacia hybrid CCoAOMT (AhCCoAOMT) was 1024-bp long, containing 750-bp coding regions, with one major open reading frame of 249 amino acids. On the other hand, full length genomic sequence of the CCoAOMT (AhgflCCoAOMT) was 2548 bp long, containing three introns and four exons with a 5' untranslated region (5'UTR) of 391 bp in length. The 5'UTR of the characterized CCoAOMT gene contains various regulatory elements. Southern analysis revealed that the Acacia hybrid has more than three copies of the CCoAOMT gene. Real-time PCR showed that this gene was expressed in root, inner bark, leaf, flower and seed pod of the Acacia hybrid. Downregulation of the homologous CCoAOMT gene in tobacco by antisense (AS) and intron-containing hairpin (IHP) constructs containing partial AhCCoAOMT led to reduction in lignin content. Expression of the CCoAOMT in AS line (pART-HAS78-03) and IHP line (pART-HIHP78-06) was reduced respectively by 37 and 75% compared to the control, resulting in a decrease in the estimated lignin content by 24 and 56%, respectively. AhCCoAOMT was found to have altered not only S and G units but also total lignin content, which is of economic value to the pulp industry. Subsequent polymorphism analysis of this gene across eight different genetic backgrounds each of A. mangium and A. auriculiformis revealed 47 single nucleotide polymorphisms (SNPs) in A. auriculiformis CCoAOMT and 30 SNPs in A. mangium CCoAOMT.
authors.affiliation: Tree Breeding Unit, Applied Forest Science and Industry Development, Sarawak Forestry Corporation, Kuching, Sarawak, Malaysia.
authors.forename: S L
authors.initials: SL
authors.lastname: Pang
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia.
authors.forename: S S
authors.initials: SS
authors.lastname: Ong
authors.affiliation: Department of Biological Science, Faculty of Science, Universiti Tunku Abdul Rahman, Kampar, Perak, Malaysia.
authors.forename: H H
authors.initials: HH
authors.lastname: Lee
authors.affiliation: School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.
authors.forename: Z
authors.initials: Z
authors.lastname: Zamri
authors.affiliation: Malaysia Biotechnology Corporation, Kuala Lumpur, Malaysia.
authors.forename: K I
authors.initials: KI
authors.lastname: Kandasamy
authors.affiliation: School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.
authors.forename: C Y
authors.initials: CY
authors.lastname: Choong
authors.affiliation: School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia wicki@ukmi.edu.my.
authors.forename: R
authors.initials: R
authors.lastname: Wickneswari
mesh_terms: D000045:Acacia / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D023061:Gene Order; D005822:Genetic Vectors / Q000235:genetics; D006824:Hybridization, Genetic; D008031:Lignin / Q000096:biosynthesis*; D008780:Methyltransferases / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics; D018547:Plant Stems / Q000166:cytology / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D050436:Regulatory Elements, Transcriptional; D016415:Sequence Alignment; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D008031:Lignin; D008780:Methyltransferases; C059825:caffeoyl-CoA O-methyltransferase