Overexpression of an apoplastic peroxidase gene CrPrx in transgenic hairy root lines of Catharanthus roseus
- 374 Downloads
Peroxidases are a family of isoenzymes found in all higher plants and are known to be involved in a broad range of physiological processes. However, very little information is available concerning their role in Catharanthus roseus. The present study describes the impact of both overexpression and suppression of a peroxidase gene, CrPrx in C. roseus transgenic hairy root lines. Real-time PCR analysis in 35S-CrPrx and CrPrx-RNAi transgenic lines indicated differential transcript profile for peroxidases as well as for genes and regulators involved in MIA (monoterpenoid indole alkaloid) pathway of C. roseus. Comparative analysis revealed that MIA pathway genes showing elevated levels of expression in 35S-CrPrx transgenic lines showed a significant reduction in their transcript level in CrPrx-RNAi transgenic lines. Metabolite analysis detected higher levels of ajmalicine and serpentine accumulation in overexpressed lines. It was observed that all overexpressed transgenic lines produced more amount of H2O2. These results indicate a role of CrPrx gene in the regulation of MIA pathway genes and regulators, thus affecting the production of specific alkaloids.
KeywordsAgrobacterium rhizogenes Catharanthus roseus Monoterpenoid indole alkaloids Peroxidases Transgenic hairy roots
MJ and SK thank Council of Scientific and Industrial Research (CSIR), India for the award of senior research fellowships. The authors are grateful to Dr. Peter Waterhouse of CSIRO Plant Industry, Canberra, Australia, for kindly providing vectors pKANNIBAL and pART27. The work is supported by financial assistance from the core grant of National Institute of Plant Genome Research, New Delhi, India.
- Bhattacharjee S (2005) Reactive oxygen species and oxidative burst: roles in stress, senescence and signal transduction in plant. Curr Sci 89:1113–1121Google Scholar
- Blom TJM, Sierra MI, Van Vliet TB, Franke-van Dijk MEI, de Koning P, Van Iren F, Verpoorte R, Libbenga KR (1991) Uptake and accumulation of ajmalicine in to isolated vacuoles of cultured cells of Catharanthus roseus (L.) G. Don and its conversion in to serpentine. Planta 183:170–177CrossRefGoogle Scholar
- Costa MM, Hilliou F, Duarte P, Pereira LG, Almeida I, Leech M, Memelink J, Barceló AR, Sottomayor M (2008) Molecular cloning and characterization of a vacuolar class III peroxidase involved in the metabolism of anticancer alkaloids in Catharanthus roseus. Plant Physiol 146:403–417CrossRefGoogle Scholar
- Eisen MB, Spellman PT, Brown PO, Botstein D (1998) Cluster analysis and display of genome-wide expression patterns. Proc Natl Acad Sci USA 97:4985–4990Google Scholar
- Hilliou F, van der Fits L, Memelink J (2001) Molecular regulation of monoterpenoid indole alkaloid biosynthesis. In: Romeo JT, Sanders JA, Matthews BF (eds) Recent advances in phytochemistry: regulation of phytochemicals by molecular techniques, vol 35. Elsevier Science, Oxford, pp 275–295CrossRefGoogle Scholar
- Lane BG, Dunwell JM, Ray JA, Schmitt MR (1993) Germin, a protein marker of early plant development, is an oxalate oxidase. J Biol Chem 268:12239–12242Google Scholar
- Menke FLH, Kijne JW, Memelink J (1996) Digging for gene expression levels in Catharanthus roseus: nonradioactive detection of plant mRNA levels. In: Leous M, Matter K, Schroder C, Ziebolz B (eds) Biochemica 2. Boehringer-Mannheim, Mannheim, pp 16–18Google Scholar
- Suttipanta N, Pattanaik S, Gunjan S, Xie CH, Littleton J, Yuan L (2007) Promoter analysis of the Catharanthus roseus geraniol 10-hydroxylase gene involved in terpenoid indole alkaloid biosynthesis. Biochim Biophys Acta 1769:139–148Google Scholar
- Wang GL, Fang HJ (1998) Plant genetic engineering, 2nd edn. Science, BeijingGoogle Scholar