Project description:Using chromatin conformation capture methods, we learned that the latent episome of the human Epstein-Barr virus (EBV) displays preferential chromosome association that correlates with gene density. The episome avoids gene-rich chromosomes and favors gene-poor chromosomes. Kaposi’s sarcoma-associated herpesvirus behaves similarly, but human papillomavirus does not, suggesting limited evolutionary conservation of this strategy. Moreover, the strongest contacts we detected between the human genome and EBV episome localized to OriP, the latent origin of replication. This genetic element, and the EBNA1 protein that binds there, are sufficient to reconstitute chromosome association preferences of the entire episome. Upon reactivation from latency, however, these preferences are lost. Detailed mapping of changes in interchromosomal contacts reveal that the episome moves away from repressive heterochromatin and toward activating euchromatin. Our work adds three-dimensional relocalization to the molecular events that occur during the genetic switch from EBV latency to reactivation. The involvement of only a myriad of interchromosomal contacts also argues for a possible role of this type of long-range association in gene regulation.
Project description:Using chromatin conformation capture methods, we learned that the latent episome of the human Epstein-Barr virus (EBV) displays preferential chromosome association that correlates with gene density. The episome avoids gene-rich chromosomes and favors gene-poor chromosomes. Kaposi’s sarcoma-associated herpesvirus behaves similarly, but human papillomavirus does not, suggesting limited evolutionary conservation of this strategy. Moreover, the strongest contacts we detected between the human genome and EBV episome localized to OriP, the latent origin of replication. This genetic element, and the EBNA1 protein that binds there, are sufficient to reconstitute chromosome association preferences of the entire episome. Upon reactivation from latency, however, these preferences are lost. Detailed mapping of changes in interchromosomal contacts reveal that the episome moves away from repressive heterochromatin and toward activating euchromatin. Our work adds three-dimensional relocalization to the molecular events that occur during the genetic switch from EBV latency to reactivation. The involvement of only a myriad of interchromosomal contacts also argues for a possible role of this type of long-range association in gene regulation.
Project description:Using chromatin conformation capture methods, we learned that the latent episome of the human Epstein-Barr virus (EBV) displays preferential chromosome association that correlates with gene density. The episome avoids gene-rich chromosomes and favors gene-poor chromosomes. Kaposi’s sarcoma-associated herpesvirus behaves similarly, but human papillomavirus does not, suggesting limited evolutionary conservation of this strategy. Moreover, the strongest contacts we detected between the human genome and EBV episome localized to OriP, the latent origin of replication. This genetic element, and the EBNA1 protein that binds there, are sufficient to reconstitute chromosome association preferences of the entire episome. Upon reactivation from latency, however, these preferences are lost. Detailed mapping of changes in interchromosomal contacts reveal that the episome moves away from repressive heterochromatin and toward activating euchromatin. Our work adds three-dimensional relocalization to the molecular events that occur during the genetic switch from EBV latency to reactivation. The involvement of only a myriad of interchromosomal contacts also argues for a possible role of this type of long-range association in gene regulation.
Project description:Using chromatin conformation capture methods, we learned that the latent episome of the human Epstein-Barr virus (EBV) displays preferential chromosome association that correlates with gene density. The episome avoids gene-rich chromosomes and favors gene-poor chromosomes. Kaposi’s sarcoma-associated herpesvirus behaves similarly, but human papillomavirus does not, suggesting limited evolutionary conservation of this strategy. Moreover, the strongest contacts we detected between the human genome and EBV episome localized to OriP, the latent origin of replication. This genetic element, and the EBNA1 protein that binds there, are sufficient to reconstitute chromosome association preferences of the entire episome. Upon reactivation from latency, however, these preferences are lost. Detailed mapping of changes in interchromosomal contacts reveal that the episome moves away from repressive heterochromatin and toward activating euchromatin. Our work adds three-dimensional relocalization to the molecular events that occur during the genetic switch from EBV latency to reactivation. The involvement of only a myriad of interchromosomal contacts also argues for a possible role of this type of long-range association in gene regulation.
Project description:The human genome is structurally organized in three-dimensional space to facilitate functional partitioning of transcription. We learned that the latent episome of the human Epstein-Barr virus (EBV) preferentially associates with gene-poor chromosomes and avoids gene-rich chromosomes. Kaposi's sarcoma-associated herpesvirus behaves similarly, but human papillomavirus does not. Contacts on the EBV side localize to OriP, the latent origin of replication. This genetic element and the EBNA1 protein that binds there are sufficient to reconstitute chromosome association preferences of the entire episome. Contacts on the human side localize to gene-poor and AT-rich regions of chromatin distant from transcription start sites. Upon reactivation from latency, however, the episome moves away from repressive heterochromatin and toward active euchromatin. Our work adds three-dimensional relocalization to the molecular events that occur during reactivation. Involvement of myriad interchromosomal associations also suggests a role for this type of long-range association in gene regulation.IMPORTANCE The human genome is structurally organized in three-dimensional space, and this structure functionally affects transcriptional activity. We set out to investigate whether a double-stranded DNA virus, Epstein-Barr virus (EBV), uses mechanisms similar to those of the human genome to regulate transcription. We found that the EBV genome associates with repressive compartments of the nucleus during latency and with active compartments during reactivation. This study advances our knowledge of the EBV life cycle, adding three-dimensional relocalization as a novel component to the molecular events that occur during reactivation. Furthermore, the data add to our understanding of nuclear compartments, showing that disperse interchromosomal interactions may be important for regulating transcription.