A grape bud EST library was constructed and 4270 ESTs sequenced. The library clones were arrayed for the purpose of investigating the level of gene expression over time, particularly leading up to the buds' release from dormancy. The arrays were hybridized with P(33)-labeled probes produced from samples of buds collected at weekly intervals. These probes covered the time from 9 weeks prior to bud burst until just after the emergence of the shoots. Expression patterns from these genes have been examined. It was found that 74% of the genes in the data set were homologous to known proteins. Genes were then assigned to functional categories according to their primary BLAST match. Of these 13% were involved with photosynthesis, 13% with disease resistance and defense, 5% energy, 12% metabolism, 20% protein production and processing, 25% cell structure and plant growth and the remaining 12% were unclassified The expression pattern of a selection of "candidate" genes retrieved from literature previously reporting an association with dormancy changes was assessed. On closer examination most of these genes relate to the oxidative processes and stress responses within the cell. The results of this study show that even in the dormant state, gene expression in the buds is high.

SummarySerial analysis of gene expression (SAGE) was applied to the major cereal crop barley ( Hordeum vulgare ) to characterize the transcriptional profile of grain during the malting process. Seven SAGE libraries were generated from seed at different time points during malting, in addition to one library from dry mature seed. A total of 155 206 LongSAGE tags, representing 41 909 unique sequences, was generated. This study reports an in-depth analysis of the most abundant transcripts from each of eight specific time points in a malting barley time course. The 100 most abundant tags from each library were analysed to identify the putative functional role of highly abundant transcripts. The largest functional groups included transcripts coding for stress response and cell defence, ribosomal proteins and storage proteins. The most abundant tag represented B22EL8, a barley metallothionein, which showed significant up-regulation across the malting time course. Considerable changes in the abundance profiles of some of the highly abundant tags occurred at 24 h post-steeping, indicating that it may be an important time point for gene expression changes associated with barley seed germination.

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Advances in genomics have provided technologies for high throughput analysis of plant genomes with potential for use in gene discovery in germplasm collections. The establishment of DNA banks facilitates this screening by making DNA from large numbers of plant accessions widely available. DNA banks require the development of appropriate policies for access and benefit sharing. Tools for automating sample and data handling are essential. Standard molecular methods for fingerprinting DNA accessions for international comparisons need to be determined. New screening technologies are required to take advantage of the emerging availability of large DNA collections. The Australian Plant DNA Bank aims to collect DNA from all Australian plant species and to sample the diversity within each species. DNA from all individuals of the species is being stored for rare species. Domesticated or economically important species from all countries are also being collected and stored. International networking of DNA banks will be a key step in linking genomics tools to global plant diversity.

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