A novel PR10 promoter from Erianthus arundinaceus directs high constitutive transgene expression and is enhanced upon wounding in heterologous plant systems
In genetic engineering, inducible promoters play an important role as the expression of genes driven by them can be turned on or off under situations like biotic or abiotic factors. There are few reports on inducible promoters that can be employed in the development of transgenic plants, particularly in sugarcane. In the present study, four wound inducible genes (Chitinase, PR1A, PR10 and HRGP) were selected and were amplified from Erianthus arundinaceus, a distant relative of sugarcane. In order to determine the gene that is highly induced upon wounding, RT-qPCR was performed, which showed that PR10 gene expression was instantaneous and higher upon wounding when compared to the other three genes. Using the random amplification of genomic ends technique, a 592 bp promoter sequence was obtained and in silico analysis of the upstream regulatory region revealed a 469 bp promoter and 123 bp of 5′ untranslated region (UTR). Functional analyses of the promoter sequence (with and without 5′ UTR) in tobacco, rice and sugarcane using β-glucuronidase (GUS) as the reporter gene revealed the constitutive and inducible nature of the PR10 promoter. Our studies have demonstrated that the PR10 promoter, though highly constitutive, was quickly induced upon wounding as well as on treatment with abscisic acid and methyl jasmonate hormones. This is the first report on the isolation and characterization of a PR10 promoter from a wild grass and is expected to have application for development of transgenic plants.
KeywordsInducible promoter PR10 Wounding Erianthus 5′ regulatory sequence
The authors would like to thank the Indian Council of Agricultural Research, New Delhi and Sugarcane Breeding Institute, Coimbatore, India for the funding and infrastructure.
- 8.Kuriakose B, Ganesan V, Thomas G, Viswanathan A, Anand N (2009) Random amplification of genomic ends (RAGE) as an efficient method for isolation and cloning of promoters and uncloned genomic regions. Afr J Biotechnol 8(19):4765–4773Google Scholar
- 14.Arvinth S, Arun S, Selvakesavan RK, Srikanth J, Mukunthan N, Kumar PA, Premachandran MN, Subramonian N (2010) Genetic transformation and pyramiding of aprotinin-expressing sugarcane with cry1Ab for shoot borer (Chilo infuscatellus) resistance. Plant Cell Rep 29(4):383–395PubMedCrossRefGoogle Scholar
- 25.Gowik U, Burscheidt J, Akyildiz M, Schlue U, Koczor M, Streubel M, Westhoff P (2004) cis-Regulatory elements for mesophyll-specific gene expression in the C4 plant Flaveria trinervia the promoter of the C4 phosphoenolpyruvate carboxylase gene. Plant Cell 16(5):1077–1090PubMedCrossRefPubMedCentralGoogle Scholar
- 41.Lo SCC, Hipskind JD, Nicholson RL (1999) cDNA cloning of a sorghum pathogenesis-related protein (PR-10) and differential expression of defense-related genes following inoculation with Cochliobolus heterostrophus or Colletotrichum sublineolum. Mol Plant-Microbe Interact 12:479–489PubMedCrossRefGoogle Scholar