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Smc5/6: a link between DNA repair and unidirectional replication?

Abstract

Of the three structural maintenance of chromosome (SMC) complexes, two directly regulate chromosome dynamics. The third, Smc5/6, functions mainly in homologous recombination and in completing DNA replication. The literature suggests that Smc5/6 coordinates DNA repair, in part through post-translational modification of uncharacterized target proteins that can dictate their subcellular localization, and that Smc5/6 also functions to establish DNA-damage-dependent cohesion. A nucleolar-specific Smc5/6 function has been proposed because Smc5/6 yeast mutants display penetrant phenotypes of ribosomal DNA (rDNA) instability. rDNA repeats are replicated unidirectionally. Here, we propose that unidirectional replication, combined with global Smc5/6 functions, can explain the apparent rDNA specificity.

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Figure 1: Unidirectional replication.

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Correspondence to Antony M. Carr.

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Murray, J., Carr, A. Smc5/6: a link between DNA repair and unidirectional replication?. Nat Rev Mol Cell Biol 9, 177–182 (2008). https://doi.org/10.1038/nrm2309

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