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To help develop an understanding of the genes that govern the developmental characteristics of the potato (Solanum tuberosum), as well as the genes associated with responses to specified pathogens and storage conditions, The Canadian Potato Genome Project (CPGP) carried out 5' end sequencing of regular, normalized and full-length cDNA libraries of the Shepody potato cultivar, generating over 66,600 expressed sequence tags (ESTs). Libraries sequenced represented tuber developmental stages, pathogen-challenged tubers, as well as leaf, floral developmental stages, suspension cultured cells and roots. All libraries analysed to date have contributed unique sequences, with the normalized libraries high on the list. In addition, a low molecular weight library has enhanced the 3' ends of our sequence assemblies. Using the combined assembly dataset, unique tuber developmental, cold storage and pathogen-challenged sequences have been identified. A comparison of the ESTs specific to the pathogen-challenged tuber and foliar libraries revealed minimal overlap between these libraries. Mixed assemblies using over 189,000 potato EST sequences from CPGP and The Institute for Genomics Research (TIGR) has revealed common sequences, as well as CPGP- and TIGR-unique sequences.

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As part of a large-scale genomics project focused on understanding and improving the Shepody potato, we have increased the regeneration and transformation rates for this cultivar. Using combinations of auxins and trans-zeatin, leaf and stem explants were evaluated for callus induction and shoot formation. Several plant growth regulator combinations resulted in higher plant regeneration rates over a previous method. Using the best combination of auxin and cytokinin in combination with Agrobacterium-mediated transformation, we regenerated independent putative transformants from 59.5% of the total explants plated. We ran PCR on a sample of the plants to confirm transformation and 47.1% were nptII positive; giving a confirmed transformation rate of 28.0%.

Among several wheat (Triticum aestiyum L.) germ proteins able to lyse Micrococcus lysodeikticus, one lysozyme (WI A) was purified by ionexchange chromatography, gel filtration, and preparative polyacrylamide gel electrophoresis. Polyclonal antibodies against this lysozyme were raised in rabbits. The in situ localization of WlA lysozyme was achieved by the indirect protein A-gold technique. Large amounts of WIA lysozyme were found in cell walls whereas intercellular spaces, cytoplasm, and organelles were nearly free of labeling. Specificity of labeling was assessed with several controls. In an attempt to detect the presence of binding sites, WlA lysozyme was complexed to colloidal gold. Particles were specifically distributed in large amounts over wheat embryo and coleoptile cell walls. The absence of labeling over isolated coleoptile cell walls treated with 0.1 and 0.4 molar potassium hydroxide for hemicellulose extraction indicated that WlA lysozyme binding sites were probably of hemicellulosic nature.