A general cloning strategy for divergent plant cytochrome P450 genes and its application in Lolium rigidum and Ocimum basilicum

The investigation of plant cytochrome P450 genes and enzymes is a field of growing interest. Apparently, an even greater diversity of cytochrome P450 genes exists in plants in comparison to other eukaryotes. This may be due t o their role in the biosynthesis of secondary metabolites that are present in plants in an enormous variety. Most cloning approaches are hampered by t he large sequence diversity of plant cytochrome P450 genes. We present a me thod to clone divergent cytochrome P450 ESTs by a nested RT-PCR-strategy. T hese ESTs were used for the subsequent cloning of the corresponding full-si ze cDNAs of divergent families via cDNA-library screening. Sixteen cytochro me P450 genes belonging to different cytochrome P450-families have been ide ntified in this way, proving the efficacy of the strategy.