Hierarchical clustering analysis of the expression patterns of DEP spots in wheat embryo and endosperm during seed germination. Clustering was based on the protein expression levels across phase I, II, III, and IV of seed germination. Red color indicates a positive abundance in protein spots; green indicates a negative abundance in protein spots. Different expression trends of DEP spots identified in embryo and endosperm were classified. Embryo: a. down-up regulation; b. up-regulation; c. up-down-up regulation; d. down regulation; e. up-down regulation. Endosperm: f. down-up regulation; g. up-regulation; h. down-regulation.