Cdc6, or cell division cycle 6, is a protein in eukaryotic cells. CDC6 is an ATP binding protein and a member of the pre-replicative complex (pre-RC) together with the origin recognition complex (ORC), Cdt1 and the MCM complex (containing MCM2-7p). CDC6 assembles after ORC in an ATP dependent manner and is required for loading MCM proteins onto the DNA. It is thought that the CDC6-Cdt1 complex uses ATP hydrolysis to thread DNA through the central hole of the MCM doughnut. Mutations in the binding motif of CDC6 strongly suggest that ATP binding and hydrolysis is essential for its function. The minimal requirement for DNA binding has been mapped within its 47-amino acid sequence. Furthermore, Cdc6 indirectly inhibits activation of the p34cdc2/CDC28 M phase kinase, thus nuclear division is suppressed.