|PROSITE documentation PDOC51131 [for PROSITE entry PS51131]|
The MRN complex (Mre11-Rad50-Nbs1) plays an important role in many DNA metabolic events that involve DNA double-stranded breaks. MRN is one of the first factors to be localized to DNA lesions where it might have a structural role by tethering and stabilizing broken chromosomes [1,2].
Rad50 is a split ABC-type ATPase; its center contains a long heptad repeat that folds into an antiparallel coiled coil, bringing the N-terminal (Walker A) and the C-terminal (Walker B) domains in close proximity (see <PDB:1L8D>) . The apex of the coiled coil contains a dimerization interface, a conserved Cys-x-x-Cys motif in a hook-shaped domain that dimerizes with a second hook domain via cysteine-mediated zinc ion coordination (see the schematic representation below). This zinc dependent dimerization event allows the formation of a complex that has appropriate lenghts and conformational proporties to link sister chromatids in homologous recombination and DNA ends in non-homologous end-joining.
x x x x x x x x x x x x x x x x C C x x x x x x x x x \ / x x x x x x x x Zn x x x x x x x x / \ x x x x x x x x x C C x x x x x x x x x x x x x x x x coiled coil coiled coil
'C': conserved cysteine involved in zinc binding.
The profile we developed covers the two cysteines and the coiled coil region.Last update:
June 2005 / First entry.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||van den Bosch M. Bree R.T. Lowndes N.F.|
|Title||The MRN complex: coordinating and mediating the response to broken chromosomes.|
|Source||EMBO Rep. 4:844-849(2003).|
|2||Authors||de Jager M. van Noort J. van Gent D.C. Dekker C. Kanaar R. Wyman C.|
|Title||Human Rad50/Mre11 is a flexible complex that can tether DNA ends.|
|Source||Mol. Cell 8:1129-1135(2001).|
|3||Authors||Hopfner K.P. Craig L. Moncalian G. Zinkel R.A. Usui T. Owen B.A. Karcher A. Henderson B. Bodmer J.L. McMurray C.T. Carney J.P. Petrini J.H. Tainer J.A.|
|Title||The Rad50 zinc-hook is a structure joining Mre11 complexes in DNA recombination and repair.|