The breeding of disease resistant plants is one of the major goals of plant biotechnology. Various resistant genes and anti-fungal components are known and our knowledge about defense mechanisms helped us to find the best way for engineering resistant plants. Also there are good facilities fQr gene delivery and plant tissue culture techniques at least for major crops. Construction of efficient promoters is very important step to regulate the trans genes expression in plants. Different promoters containing various properties are defined and used to express trans genes in plants, (e.g. constitutive promoters, Tissue-specific promoters, Chemically and Physically inducible promoters, Pathogen-inducible promoters). But an ideal promoter should have some specification, i.g. it should be activated rapidly, strongly enough and locally in response to a wide range of pathogens and inactivated under disease-free conditIOD.S. Also it should be activated in all tissues that could be attacked by the pathogens. In this study we have tried to design and construct a pool of synthetic promoters using defined e;ements in pathogen inducible promoters. In construction procedures various combinations and copy number of specific cis elements are fused with minimal promoter and reporter gene (GUS). Three cis acting elements were selected, synthesied and cloned in pACYC177 vector. Positive colonies were selected by insertional inactivation technique. The segments were cloned using suitable restriction sites in upstream of GUS gene in pSH4. The regulatory cassettes fused with GUS subcloned in a plant expression vector. The cloning was confirmed using PCR, digestion pattern, and sequenc;:ing. Eleven synthetic promoters, a positive and a negative control have been constracted and their stringency and inducibility in canola plant are evaluated using transient expression.

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