In a paper published online in advance in Molecular Cell this week, researchers at the University of Zurich show that poly(ADP-ribose)-polymerase-1, or PARP1/ARTD1, "is implicated in the maintenance of silent rDNA chromatin during cell division." More specifically, the team shows that "PARP1 associates with TIP5 … via the noncoding pRNA and binds to silent rRNA genes after their replication in mid-late S phase," such that it represses rRNA transcription and plays a role in the formation of silent rDNA chromatin. Overall, the Zurich team says its examination of the functions of PARP1 points to just "how epigenetic marks are transmitted during each cell cycle."
In the current issue of Cell, a team led by investigators at BGI-Shenzhen reports on its application of a high-throughput whole-genome single-cell sequencing method to two cells derived from a lymphoblastoid cell line. The team also "carried out whole-exome single-cell sequencing of 90 cells from a JAK2-negative myeloproliferative neoplasm patient." The BGI-led group says its sequencing data highlight "essential thrombocythemia-related candidate mutations such as SESN2 and NTRK1, which may be involved in neoplasm progression."
Another BGI-led team reports having performed single-cell exome sequencing on a clear cell renal cell carcinoma tumor and adjacent kidney tissue. "Analyses of these data allowed us to delineate a detailed intratumoral genetic landscape at a single-cell level," the authors write in Cell. "Our pilot study demonstrates that ccRCC [clear cell renal cell carcinoma tumor] may be more genetically complex than previously thought and provides information that can lead to new ways to investigate individual tumors, with the aim of developing more effective cellular targeted therapies."