Structural biology of Rad50 ATPase: ATP-driven conformational control in DNA double-strand break repair and the ABC-ATPase superfamily.
To clarify the key role of Rad50 in DNA double-strand break repair (DSBR), we biochemically and structurally characterized ATP-bound and ATP-free Rad50 catalytic domain (Rad50cd) from Pyrococcus furiosus. Rad50cd displays ATPase activity plus ATP-controlled dimerization and DNA binding activities. Rad50cd crystal structures identify probable protein and DNA interfaces and reveal an ABC-ATPase fold, linking Rad50 molecular mechanisms to ABC transporters, including P glycoprotein and cystic fibrosis transmembrane conductance regulator. Binding of ATP gamma-phosphates to conserved signature motifs in two opposing Rad50cd molecules promotes dimerization that likely couples ATP hydrolysis to dimer dissociation and DNA release. These results, validated by mutations, suggest unified molecular mechanisms for ATP-driven cooperativity and allosteric control of ABC-ATPases in DSBR, membrane transport, and chromosome condensation by SMC proteins.
Hopfner
K P
KP
Department of Molecular Biology and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Karcher
A
A
Shin
D S
DS
Craig
L
L
Arthur
L M
LM
Carney
J P
JP
Tainer
J A
JA
D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000235:genetics; D000595:Amino Acid Sequence; D004260:DNA Repair; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D011487:Protein Conformation; D020027:Pyrococcus furiosus; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment
D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C086930:RAD50 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D000251:Adenosine Triphosphatases