Cinnamyl alcohol dehydrogenase (CAD) is one of the regulating enzymes that catalyzes the reduction of cinnamaldehydes to ρ-coumaryl, coniferyl and sinapyl alcohols during the final stage of lignin biosynthesis pathway. The expression of CAD genes is believed to be important towards the phenotype characteristics of plants. A full-length CAD cDNA sequence was successfully inferred from the Neolamarckia cadamba wood formation genomic resource database (10,368 ESTs) through the contig mapping approach. Further validation by RT-PCR had confirmed the identity of the gene discovered. The full-length CAD cDNA, designated as NcCAD was 1,240 bp long with a 1,086 bp open reading frame encoding a protein of 361 amino acids, a 68 bp 5-UTR and a 86 bp 3-UTR. Phylogenetic analysis showed that NcCAD was grouped in the cluster containing both CAD and SAD genes, in which both genes were involved in lignin biosynthesis. This also showed that the NcCAD cDNA discovered may poses intermediate characteristics of both CAD and SAD genes. The full-length NcCAD cDNA discovered can serve as a good candidate gene for further insight into the wood properties of N. cadamba through association genetics study approach.
Key words: Keywords: Neolamarckia cadamba; EST database; contig mapping; RT-PCR; cinnamyl alcohol dehydrogenase (CAD)
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