Isolation and Analysis of a if3 Chitinase Promoter Fragment for the Presence of Cis-acting Regulatory Elements

An inducible if3 chitinase promoter was isolated from Lupinus albus for use in defense gene constructs to be used for engineering of fungal resistance in selected crop species. The advantage of using an inducible promoter is that it would only be switched on by fungal infection, and the gene product would only be expressed when needed, resulting in a reduction in energy cost to the plant. Cis-acting elements are considered to be important in the controlling of gene expression and a search was performed in order to identify cis-acting elements that could be of importance in the control of gene expression in the 1.81kb if3 promoter-containing fragment. The search was performed using the PlantCARE (Cis-Acting Regulatory Elements) database which identified the presence of various putative cis-acting regulatory elements. A single putative MBS regulatory cis-acting element, involved in the regulation of transcription of several plant genes in response to various environmental factors, including elicitors and wounding, was present in the 1.81kb if3 promoter-containing fragment. Several CAAT boxes were also identified within the 1.81kb promoter-containing fragment. The CAAT box plays an important role in the determination of promoter efficiency. Putative fungal elicitor activated [Box-W1 and ELI-box3], wound-inducible [WUN-3] and ERE (ethylene responsive element) cis-acting elements were also present in the 1.81kb promoter-containing fragment.