Figure 1.

S. pombe Chk1 domain structure. Chk1 has an N-terminal kinase domain (blue) and a C-terminal regulatory domain (yellow). Regions required for 14-3-3 interaction and nuclear localization [42] are indicated below the schematic. The position of S345 (orange), the site of activating phosphorylation is shown, as are the two regions of the C-terminal domain conserved across species that have been analyzed by mutagenesis [45]. These are "region 1" (green; residues 394–400, RLTRFYS in S. pombe, RMTRFYS in humans), and "region 2" (red; residues 468–477, GDPLEWRKFF in S. pombe, GDPLEWRKFY in humans).