Bre1, a conserved E3 ubiquitin ligase in Saccharomyces cerevisiae, together with its interacting partner Lge1, are responsible for histone H2B monoubiquitination, which regulates transcription, DNA replication, DNA damage response and repair, ensuring the structural integrity of the genome. Deletion of BRE1 or LGE1 also results in whole chromosome instability. We discovered a novel role for Bre1, Lge1 and H2Bub1 in chromosome segregation and sister chromatid cohesion. Bre1's function in G1 and S phases contributes to cohesion establishment, but it is not required for cohesion maintenance in G2 phase. Bre1 is dispensable for the loading of cohesin complex to chromatin in G1, but regulates the localization of replication factor Mcm10 and cohesion establishment factors Ctf4, Ctf18 and Eco1 to early replication origins in G1 and S phase, and promotes cohesin subunit Smc3 acetylation for cohesion stabilization. H2Bub1 epigenetically marks the origins, potentially signaling the coupling of DNA replication and cohesion establishment.
- Karen Wing Yee Yuen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Ali Shilatifard, Northwestern University, United States
© 2017, Zhang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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A variety of microscopy techniques are used by researchers in the life and biomedical sciences. As these techniques become more powerful and more complex, it is vital that scientific articles containing images obtained with advanced microscopes include full details about how each image was obtained. To explore the reporting of such details we examined 240 original research articles published in eight journals. We found that the quality of reporting was poor, with some articles containing no information about how images were obtained, and many articles lacking important basic details. Efforts by researchers, funding agencies, journals, equipment manufacturers and staff at shared imaging facilities are required to improve the reporting of experiments that rely on microscopy techniques.
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