Publications by authors named "Divyasree Poovathumkadavil"
Article Synopsis
- - The MCM motor, initially inactive as a double hexamer, is crucial for DNA replication and becomes activated through the recruitment of proteins GINS and Cdc45 during the S-phase of the cell cycle.
- - Research reveals that the metazoan protein Downstream neighbor of Son (DONSON) plays a key role in the assembly of active CMG helicases by delivering GINS to MCM, though the specific effects on the MCM structure were unclear prior to this study.
- - Using cryoelectron microscopy on Xenopus egg extracts, the study identifies a double CMG complex connected by a DONSON dimer, showing that this tethering is vital for DNA replication, with mutations in DONSON linked to issues in human
Article Synopsis
- Cell division depends on accurate DNA replication, and errors during this process can lead to serious health issues like cancer and premature aging.
- TRAIP E3 ubiquitin ligase is crucial for maintaining genome integrity and cell survival, and its dysfunction is linked to conditions like primordial dwarfism.
- Research using the auxin-induced degron system showed that when TRAIP is depleted, cells stop dividing during the S-phase, get stuck in the G2 phase, and eventually enter senescence due to DNA damage during transcription.
Complex cellular processes are driven by the regulated assembly and disassembly of large multiprotein complexes. While we are beginning to understand the molecular mechanism for assembly of the eukaryotic DNA replication machinery (replisome), we still know relatively little about the regulation of its disassembly at replication termination. Recently, the first elements of this process have emerged, revealing that the replicative helicase, at the heart of the replisome, is polyubiquitylated prior to unloading and that this unloading requires p97 segregase activity.
View Article and Find Full Text PDFWe have shown previously that the process of replication machinery (replisome) disassembly at the termination of DNA replication forks in the S-phase is driven through polyubiquitylation of one of the replicative helicase subunits (Mcm7) by Cul2 ubiquitin ligase. Interestingly, upon inhibition of this pathway in embryos, the replisomes retained on chromatin were unloaded in the subsequent mitosis. Here, we show that this mitotic replisome disassembly pathway exists in egg extract and we determine the first elements of its regulation.
View Article and Find Full Text PDFArticle Synopsis
- Most metazoan embryos, including zebrafish, experience rapid cell divisions that are transcriptionally silent until a stage called the mid-blastula transition (MBT), but some genes are activated earlier.
- Researchers identified and analyzed unique transcription compartments responsible for early gene expression in zebrafish using a innovative real-time imaging technique.
- These compartments, which contain nascent RNAs and active Polymerase II, play a significant role in the early embryonic transcription process before MBT and help create a supportive environment for gene activation.