Figure 3.

Homologues of chromatin-modifying complexes regulating mammalian ESCs are overexpressed in neoblasts and functionally important. (A–D) Core components of four chromatin remodelling complexes with known functions in mammalian ESCs. Solid symbols represent genes for which we could identify homologues in planaria. Components with unclear homology are shaded. (A) BAF, (B) MLL/COMPASS, (C) PRC2 (PcG), and (D) PAF1. For a single component of each complex, expression in the three FACS fractions is indicated and ISH shows enhanced neoblast expression. Asterisks mark the midline posterior to the pharynx where neoblasts are concentrated. (E) RNAi knockdown of Smed-BRG1L, Smed-SMARCC2 (BAF170 homologue), and Smed-CTR9 completely blocked regeneration of animals amputated at day 12 (d12). Trunk region of control and RNAi worms is shown at day 2, 6, and 12 after amputation. The phenotype was penetrant in each case (observed for >5 animals). Scale bars are 0.5 mm in (A–D) and 1 mm in (E).