Figure 1.

Domain organization of metazoan Orc6 protein. Orc6 protein consists of the N-terminal TFIIB-like domain important for DNA binding, and C-terminal domain required for the interaction with core ORC. Drosophila and human N-terminal domains share 27% amino acid identity and 48% similarity. C-terminal domains have only 15% amino acid identity and 22% similarity. The resulting amino acid changes from the new MGS mutation, the conservative lysine at position 23 (K23E), as well as the previously described C-terminal MGS mutation (Y225S) are indicated in red.