Characterization and induction of two cytochrome P450 genes, CYP6AE28 and CYP6AE30, in Cnaphalocrocis medinalis: Possible involvement in metabolism of rice allelochemicals

Abstract

Two cDNAs specifi c for P450 genes, CYP6AE28 and CYP6AE30, have been isolated from the rice leaf folder Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae). Both cDNApredicted proteins have 504 amino acid residues in length, but with molecular masses of 60177 Dalton for CYP6AE28 and 60020 Dalton for CYP6AE30, and theoretical pI values of 8.49 for CYP6AE28 and 8.56 for CYP6AE30, respectively. Both putative proteins contain the conserved structural and functional domains characteristic of all CYP6 members. CYP6AE28 and CYP6AE30 show 52% amino acid identity to each other; both of them have 49 - 56% identities with CYP6AE1, Cyp6ae12, and CYP6AE14. Phylogenetic analysis showed that the two P450s are grouped in the lineage containing some of the CYP6AE members, CYP6B P450s and CYP321A1. The transcripts of CYP6AE28 and CYP6AE30 were found to be induced in response to TKM-6, a rice variety with high resistance to C. medinalis. The results suggest that the two P450s may play important roles in adaptation to the host plant rice. This is the fi rst report of P450 genes cloned in C. medinalis.©2010 Verlag der Zeitschrift für Naturforschung, Tübingen.