Functional analyses of candidate genes from the RefSeq database. Expression profiles and RNAi phenotypes are shown for a set of selected genes. A, Rab-11B; B, Rab-39; C, Rac-1; D, Hsp40; E, Hsp60; F, Hsp70; G, Hunchback-like; H, PrkC; I, Smed-SmB. Expression analyses by whole mount in situ hybridization in intact (A1-I1) and regenerating (A2-I2) animals are shown. In regenerating animals, the genes are expressed in the blastema and postblastema regions, areas where the neoblasts represent the main population during regeneration. In intact animals, the signal is weak for some of the genes analyzed, although the genes for which expression was detectable presented a pattern with a typical neoblast distribution. This pattern encompasses the parenchyma of the whole body excluding the gut, pharynx, and the anterior region of the head. Knock-down experiments by RNA interference were performed to further address the association of the selected genes with neoblasts (A3-I3). Detectable phenotypes were obtained in all cases except for B3 and G3. A3, E3, F3 and I3 show the phenotypes affecting the regeneration process, while C3, D3, and H3 show phenotypes affecting the intact animals. Scale bars: 250 μm.