Isolation and characterization of a gene encoding cinnamate 4-hydroxylase from Parthenocissus henryana.

Cinnamate 4-hydroxylase (C4H, EC 1.14.13.11) plays an important role in the phenylpropanoid pathway, which produces many economically important secondary metabolites. A gene coding for C4H, designated as PhC4H (GenBank accession no. DQ211885) was isolated from Parthenocissus henryana. The full-length PhC4H cDNA is 1,747 bp long with a 1,518-bp open reading frame encoding a protein of 505 amino acids, a 40-bp 5' non-coding region and a 189-bp 3'-untranslated region. Secondary structure of the deduced PhC4H protein consists of 41.78% alpha helix, 15.64% extended strand and 42.57% random coil. The genomic DNA of PhC4H is 2,895 bp long and contains two introns; intron I is 205-bp and intron II is 1,172-bp (GenBank accession no. EU440734). DNA gel blot analysis revealed that there might be a single copy of PhC4H in Parthenocissus henryana genome. By using anchored PCR, a 963-bp promoter sequence was isolated and it contains many responsive elements conserved in the upstream region of PAL, C4H and 4CL including the P-, A-, L- and H-boxes.