Smc5/6: a link between DNA repair and unidirectional replication?
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.
Johanne M. Murray and Antony M. Carr are at the Genome Damage and Stability Centre, University of Sussex, Brighton, Sussex, BN1 9RQ, UK. a.m.carr@sussex.ac.uk
Johanne M
JM
Murray
Antony M
AM
Carr
D018797:Cell Cycle Proteins / Q000378:metabolism / Q000502:physiology*; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D004249:DNA Damage; D004260:DNA Repair; D004261:DNA Replication; D004275:DNA, Ribosomal / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D008954:Models, Biological; D008957:Models, Genetic; D009687:Nuclear Proteins / Q000378:metabolism; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology; D000097722:Cohesins
D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004275:DNA, Ribosomal; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; D000097722:Cohesins; C486627:SMC5 protein, S cerevisiae; C432931:SMC5 protein, human; C486631:SMC6 protein, S cerevisiae; C432932:SMC6 protein, human