SAGE – unraveling the mysteries of germination

The blueprint to a new generation is contained within the seed. The processes in-volved in seed germination are however still somewhat a mystery on a genetic level. Byexamining the transcripts expressed at any time in the cell it is possible to determinewhich genes and their related proteins are being expressed at that precise moment intime. SAGE (Serial Analysis of Gene Expression) is a technique that allows rapid, de-tailed analysis of thousands of transcripts in a cell. The process of SAGE relies on twoprinciples. Firstly, a small sequence of nucleotides from the transcript, called a ”tag”can effectively identify the original transcript from whence it came. Secondly, linkingthese tags allows rapid sequencing analysis of multiple transcripts. The abundanceof a particular tag relates directly to the expression level of the gene from which it isderived. The analysis of gene expression of different physiological states provides bothqualitative and quantitative information. This makes it an efficient tool for gene ex-pression studies in the post-genomics era. In this study the gene expression profile ofgerminating (malting) barley is being examined at seven intervals over a time courseof 120 hours post steeping. This will be compared to a baseline of dry ungerminatedseed. The identification of genes for improved malting quality can be identified andexamined using SAGE and ultimately used for commercial improvement.