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DNA ds break repair Mre11

| posted 11 Aug, 2017 13:55
In the annotation of Biglebops_31 (27784-28920) we found multiple hits to endonucleases (Hammy_34, Vendetta_66, Splinter_66) and to exonucleases LindNT_35, Marcoliusprime_34), all with e-values of 0. HHPRED also had several hits to endo- and exo-nucleases as well as hits to MRE11 which has both activities and is a DNA double-strand break repair protein (99.5% probability, 60-70% coverage and e-values 10^-12 to 10^-14) that pairs with RAD50, an ATPase. We have no accepted annotation that would best fit this situation. Could we add a "DNA double strand break repair, Mre11-like protein" annotation function to our accepted list? I have included below, an associated paper abstract for the top hit 1ii7_A that explains the relationship of Mre11 and Rad50.

Structural biochemistry and interaction architecture of the DNA double-strand break repair Mre11 nuclease and Rad50-ATPase.

Hopfner, K.P., Karcher, A., Craig, L., Woo, T.T., Carney, J.P., Tainer, J.A.

(2001) Cell(Cambridge,Mass.) 105: 473-485

PubMed: 11371344 Search on PubMed
Primary Citation of Related Structures: 1II7 1II8
PubMed Abstract:
To clarify functions of the Mre11/Rad50 (MR) complex in DNA double-strand break repair, we report Pyrococcus furiosus Mre11 crystal structures, revealing a protein phosphatase-like, dimanganese binding domain capped by a unique domain controlling active site access. These structures unify Mre11's multiple nuclease activities in a single endo/exonuclease mechanism and reveal eukaryotic macromolecular interaction sites by mapping human and yeast Mre11 mutations. Furthermore, the structure of the P. furiosus Rad50 ABC-ATPase with its adjacent coiled-coil defines a compact Mre11/Rad50-ATPase complex and suggests that Rad50-ATP-driven conformational switching directly controls the Mre11 exonuclease. Electron microscopy, small angle X-ray scattering, and ultracentrifugation data of human and P. furiosus MR reveal a dual functional complex consisting of a (Mre11)2/(Rad50)2 heterotetrameric DNA processing head and a double coiled-coil linker.
Edited 11 Aug, 2017 13:59
| posted 14 Aug, 2017 13:50
Hi Claire,

Welkin had given the ok to add MRE11 double-strand break endo/exonuclease. See the post below:

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