Figure 42: Examples of domain accretion in chromatin proteins.

Domain accretion in various lineages before the animal divergence, in the apparent coelomate lineage and the vertebrate lineage are shown using schematic representations of domain architectures (not to scale). Asterisks, mobile domains that have participated in the accretion. Species in which a domain architecture has been identified are indicated above the diagram (Y, yeast; W, worm; F, fly; V, vertebrate). Protein names are below the diagrams. The domains are SET, a chromatin protein methyltransferase domain; SWI2, a superfamily II helicase/ATPase domain; Sa, sant domain; Br, bromo domain; Ch, chromodomain; C, a cysteine triad motif associated with the Msl-2 and SET domains; A, AT hook motif; EP1/EP2, enhancer of polycomb domains 1 and 2; Znf, zinc finger; sja, SET-JOR-associated domain (L. Aravind, unpublished); Me, DNA methylase/Hrx-associated DNA binding zinc finger; Ba, bromo-associated homology motif. a–c, Different examples of accretion.