Experimental model and changes in gene expression following injury. (A) The dorsal surface of L. stagnalis CNS and CNS injury protocol: both right parietal (RPa) nerves and right cerebral nerves (RCe) were crushed with fine forceps. Inset: a schematic diagram of the ganglia and location of injury (black lines). (B) Heat map representing the hierarchical clustering of 67 genes showing significant differential expression (P < 0.05). The expression pattern of each gene in the sham and crashed groups is displayed as a horizontal strip. For each gene, the expression ratio of the crush-operated to the sham-operated experiments is represented by the green and red scale at the bottom of the figure. The genes are numbered on the right, and the experimental groups are labelled on the bottom. (C) Ratio of the regulated EST sequences 3 hrs following CNS injury in L. stagnalis. (C1) The signal intensity of 348 genes or ESTs was differentially regulated. Open pie (80.7%) represents genes/EST's changes < 2.0-fold in signal intensity but significant (P < 0.05); grey pie (19.3%): changes ≥ 2.0-fold (P < 0.05). Dark grey: up-regulated genes (12%), and light grey: down regulated genes (7%). (C2) Ratio of the 67 differentially regulated genes, 16 (23.8%) genes have orthologous with known functions related to development, survival or signal transduction, whereas 51 (76.2%) genes have no orthologue.