Large-scale comparison of barley and wheat transcriptome. These heat maps provide a comparative overview of gene expression for 1875 barley (left) and wheat (right) sequences. The same pattern of low (blue) and high (yellow) expression is clearly seen in both datasets. For this plot, expression profiles were centered and then sorted according to a hierarchical clustering of the barley data using single linkage and a correlation distance measure. Tissue abbreviations: gem – mesocotyl, rad – radicle, roo – root, col – coleoptile, cro – crown, lea – leaf, brc – bracts, inf – inflorescence, ant – anther, pst – pistil, car5 – caryopsis, end22 – endosperm, dem22 – embryo. Developmental time points are as described in  and include 2 day old embryos (gem, rad, col), 10 cm seedlings (roo, cro, lea), prior to anthesis (brc, inf, ant, pst) as well as 5 (car5) and 22 days (end22, dem22) after pollination. (see also Materials and Methods: Microarray Experiment).