Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:5.99.1.3 (topoisomerase)
 9,911 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several homology-dependent pathways can repair potentially lethal DNA double-strand breaks (DSBs). The first step common to all homologous recombination reactions is the 5'-3' degradation of DSB ends that yields the 3' single-stranded DNA required for the loading of checkpoint and recombination proteins. In yeast, the Mre11-Rad50-Xrs2 complex (Xrs2 is known as NBN or NBS1 in humans) and Sae2 (known as RBBP8 or CTIP in humans) initiate end resection, whereas long-range resection depends on the exonuclease Exo1, or the helicase-topoisomerase complex Sgs1-Top3-Rmi1 together with the endonuclease Dna2 (refs 1-6). DSBs occur in the context of chromatin, but how the resection machinery navigates through nucleosomal DNA is a process that is not well understood. Here we show that the yeast Saccharomyces cerevisiae Fun30 protein and its human counterpart SMARCAD1 (ref. 8), two poorly characterized ATP-dependent chromatin remodellers of the Snf2 ATPase family, are directly involved in the DSB response. Fun30 physically associates with DSB ends and directly promotes both Exo1- and Sgs1-dependent end resection through a mechanism involving its ATPase activity. The function of Fun30 in resection facilitates the repair of camptothecin-induced DNA lesions, although it becomes dispensable when Exo1 is ectopically overexpressed. Interestingly, SMARCAD1 is also recruited to DSBs, and the kinetics of recruitment is similar to that of EXO1. The loss of SMARCAD1 impairs end resection and recombinational DNA repair, and renders cells hypersensitive to DNA damage resulting from camptothecin or poly(ADP-ribose) polymerase inhibitor treatments. These findings unveil an evolutionarily conserved role for the Fun30 and SMARCAD1 chromatin remodellers in controlling end resection, homologous recombination and genome stability in the context of chromatin.
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PMID:The yeast Fun30 and human SMARCAD1 chromatin remodellers promote DNA end resection. 2296 Jul 44

The study aimed to explore the underlying molecular mechanisms of CDK2 inhibition in neuroblastoma by bioinformatics analysis. Gene expression profile GSE16480 was downloaded from the Gene Expression Omnibus. The differentially expressed genes (DEGs) were identified from IMR32 between each time point and average expression of all time points. Gene significance was calculated using dSVDsig algorithm of dnet package. Protein-protein interaction (PPI) network was built. Then, integrated with gene significance, a core PPI network was detected by dNetPipeline algorithm in dnet package. Finally, pathway enrichment analysis was performed for genes in network. Totally, 1524 DEGs were identified. CCNA2 (cyclin A2), EXO1 (exonuclease 1), RAD51AP1 (RAD51 associated protein 1), TOP2A (topoisomerase (DNA) II alpha) and CDK1 (cyclin-dependent kinase 1) were selected as DEGs with higher connectivity after PPI network analysis. In the network, CCNA2, CDK1, BUB1B (BUB1 mitotic checkpoint serine/threonine kinase B) and CCNB1 (cyclin B1) were involved in cell cycle pathway. Additionally, CCNB1, CDK1, CCNE2 (Cyclin E2), and RRM2B (ribonucleotide reductase subunit M2B) were involved in p53 signaling pathway. Cell cycle and p53 signaling pathway were closely associated with neuroblastoma after CDK2 inhibition. The DEGs, such as CCNA2, CCNB1, CDK1 and RRM2B may be the potential targets for neuroblastoma.
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PMID:Microarray expression analysis of MYCN-amplified neuroblastoma cells after inhibition of CDK2. 2825 14