Isolation and Analysis of Cinnamic Acid 4-Hydroxylase Homologous Genes from a Hybrid Aspen,Populus kitakamiensis

摘要

Cinnamic acid 4-hydroxylase (CA4H) is the second enzyme involved in phenylpropanoid biosynthesis and is a member of the cytochrome P-450 superfamily. Three CA4H homologous genes,cyp73a,cyp73b,andcyp73c, and a cDNA clone ofcyp73awere isolated from a genomic library and a cDNA library of a hybrid aspen;Populus kitakamiensis, and were characterized. They might be interrupted by two introns each.cyp73aandcyp73bwere very similar to each other not only in coding regions but also in non-coding regions. Southern blot analysis showed that four homologous genes for CA4H constructed a small gene family in the diploid genome ofP. kitakamiensis.In the promoter regions, there were many common m-element-like sequences in phenylpropanoid biosynthesis genes.