Hannah L Klein

..Recombination at stalled replication forks is regulated at an early stage by sumoylation. In this issue of Cell, Branzei et al. show that the Ubc9/SUMO modification pathway controls the accumulation of cruciform structures at stalled forks...

..The mec1 checkpoint function mutant, defective in the yeast ATR homolog, results in increased recombination through a process that is distinct from that operative in wild-type cells...

..2007) show that the yeast Rad5 protein can promote error-free template switching and replication past a DNA lesion via a novel DNA unwinding reaction that also pairs nascent and parental strands...

..However, cells do not achieve wild-type growth rates, suggesting that unrepaired damage is still present and may lead to chromosome loss...

..While increased Rad51 can provide drug resistance, it also leads to increased genomic instability and may contribute to carcinogenesis...

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..Models for the role of Hpr1p in mature mRNA formation and the cause of plasmid instability in the absence of the Hpr1 protein are discussed...

..The hpr1Delta mutant acts in a pathway distinct from previously described mutants that reduce life span...

..In diploid strains, the most dramatic increase is in the abnormality of chromosome loss when a repair or damage detection pathway is defective...

..We propose that the HPR5 gene functions in the RAD6 repair pathway...

..This study addresses the role of the homologous recombination factors Rad54 and Rdh54 in cell growth, DNA damage and FLC resistance in Candida albicans...

..Because mutations in SOH1, RPB2 and SUA7 suppress the hyperrecombination phenotype of hpr1 mutants, this suggests a link between recombination in direct repeats and transcription...

..The SOH1 gene has been cloned and sequenced. The null allele is 10-fold increased for recombination as measured by deletion of a leu2 direct repeat...

..Further studies are required to show whether different recombination pathways or different outcomes of the same recombination pathway are controlled by the genes identified in this study...

..We conclude that Hpr1 is a novel eucaryotic protein, mutation of which causes an increase in mitotic intrachromosomal excision recombination, and that it may be functionally related to an activity of the topoisomerase I protein...

..The RDH54 gene is also required for meiosis as homozygous mutant diploids show very poor sporulation and reduced spore viability. The role of the RDH54 gene in mitotic repair and in meiosis and the pathway in which it acts are discussed...

..The assays, while not inclusive of all genome instability assays, give a broad assessment of general genome damage or inability to repair damage in various genetic backgrounds...

..2009) and in Molecular Cell (Andersen et al., 2009; Muñoz et al., 2009) now identify the human SLX4 and show that in association with the SLX1 endonuclease it directs the symmetric cleavage and resolution of Holliday junctions...

..The signals and controls that permit cells to transition between replication and recombination modes are now being identified...

..The ability of a pre-mRNA splicing factor to suppress the hyperrecombination phenotype of a defective PolII complex raises the possibility of integrating transcription, RNA processing, and genome stability or a second role for SUB2...

..RAD52-dependent events encompass all events that involve the initial steps of a recombination reaction, which include strand invasion to form a heteroduplex intermediate...

..The carboxyl-terminal region of the protein is shown to contain a sequence for nuclear localization. Expression of the SRS2 in yeast was examined and found to be extremely low...

..Zakharyevich et al. and De Muyt et al. now uncover a key role for Sgs1 in meiotic crossover regulation, which in turn reveals a joint molecule resolution pathway that produces the majority of crossovers in budding yeast...

..2011) and Wahba et al. (2011), provide insight into how RNA:DNA hybrids lead to genetic instability...

..These data demonstrate that Ser53 is not a requisite activating site for phosphorylation of mammalian eIF-4E in human or yeast cells, under conditions in which it participates in protein synthesis...

..We show that by directing target proteins to chaperonin, prefoldin promotes folding in an environment in which there are many competing pathways for nonnative proteins...

..Rad51 complex formation. The Rdh54 expression and purification procedures described here should facilitate the functional dissection of this DNA recombination/repair factor...

..The helicase activity, however, is not essential. Point mutants that lack ATPase/helicase activity partially complement a strain lacking Hmi1p. We suggest several possible roles for Hmi1p in mtDNA metabolism...

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