Molecular cloning and characterization of a pathogenrelated protein PR10 gene in pyrethrum (Chrysanthemum cinerariaefolium) flower response to insect herbivore

Abstract

In this study we successfully constructed a full-length cDNA library from open flower of pyrethrum (Chrysanthemum cinerariaefolium), the most well-known natural source of insecticide. By random sequencing, a gene coding pathogen-related (PR) protein PR10 was identified and characterized. It was designated as CcPR10, encoding a protein of 157 amino acids. The calculated molecular weight of the CcPR10 protein was 17.2 kDa and the theoretical isoelectric point was 5.98. Sequence analysis showed that the CcPR10 protein was highly homologous with other PR10 proteins. The expression of CcPR10 gene was examined in various tissues of mature plant by semi-quantitative reverse transcriptionpolymerase chain reaction (RT-PCR) and the result show that the expression of CcPR10 was observed in flowers and roots. The expression of CcPR10 gene was induced by wounding and jasmonic acid treatments. Moreover, CcPR10 transcript was induced by armyworm (Spodoptera litura) feeding, which suggests that CcPR10 may be involved in pyrethrum resistance to insect herbivore.

Key words: Pathogen-related, protein PR10, Pyrethrum (Chrysanthemum cinerariaefolium), cDNA library, gene cloning.