Crystal structure of human CDC7 kinase in complex with its activator DBF4

Journal Article: Nature Structural & Molecular BiologyYear Published: (2012) Volume Number: 19, Article Number: 1101-1107

Authors

Hughes,Siobhan; Elustondo,Frédéric; Di Fonzo,Andrea; Leroux,Frédéric G; Wong,Ai C; Snijders,Ambrosius P; Matthews,Stephen J; Cherepanov,Peter

CDC7 is a serine/threonine kinase that is essential for the initiation of eukaryotic DNA replication. CDC7 activity is controlled by its activator, DBF4. Here we present crystal structures of human CDC7-DBF4 in complex with a nucleotide or ATP-competing small molecules, revealing the active and inhibited forms of the kinase, respectively. DBF4 wraps around CDC7, burying approximately 6,000 Å(2) of hydrophobic molecular surface in a bipartite interface. The effector domain of DBF4, containing conserved motif C, is essential and sufficient to support CDC7 kinase activity by binding to the kinase N-terminal lobe and stabilizing its canonical αC helix. DBF4 motif M latches onto the C-terminal lobe of the kinase, acting as a tethering domain. Our results elucidate the structural basis for binding to and activation of CDC7 by DBF4 and provide a framework for the design of more potent and specific CDC7 inhibitors.