A balance between ubiquitination and deubiquitination regulates numerous cellular processes pathways, specific deubiquitinating enzymes often play the decisive role of controlling this balance. We recently reported that USP1 enzyme, which Fanconi anemia pathway by central player pathway, FANCD2, is activated WD40-repeat containing UAF1 protein through formation a stable USP1/UAF1 complex. Here we present isolation two novel multisubunit enzyme complexes USP12 USP46, respectively. Both...

Abstract Stress granules (SGs) harbour translationally stalled messenger ribonucleoproteins and play important roles in regulating gene expression cell fate. Here we show that neddylation promotes SG assembly response to arsenite-induced oxidative stress. Inhibition or depletion of key components the machinery concomitantly inhibits stress-induced polysome disassembly assembly. Affinity purification subsequent mass-spectrometric analysis Nedd8-conjugated proteins from ribosomal fractions...

Timely stalling and resumption of RNA polymerases at damaged chromatin are actively regulated processes. Prior work showed an importance FACT histone chaperone in such process. Here we provide a new role OTUD5 deubiquitinase the FACT-dependent Through DUB RNAi screen, found as specific stabilizer UBR5 E3 ligase. localizes to DNA double strand breaks (DSBs), interacts with represses Pol II elongation synthesis. co-localizes component SPT16 antagonizes H2A deposition DSB lesions. independently...

The functions of Lys63-linked polyubiquitin chains are poorly understood, as the enzymes that specifically generate conjugates. Rsp5 is a HECT (homologous to E6AP C terminus) ubiquitin ligase involved in numerous processes, and an associated deubiquitinating enzyme, Ubp2, modulates its activity. A dramatic increase conjugates was observed ubp2Δ cells. formation these Rsp5-dependent, phenotypes could be suppressed by prevention Lys63 Cell wall integrity impaired rsp5-1 cells defective...

The UAF1 (Usp1-associated factor 1) protein binds and stimulates three deubiquitinating enzymes: USP1, USP12, USP46. Although the USP1 x complex is required for regulation of Fanconi anemia (FA) DNA repair pathway, less known about USP12 USP46 complexes. To understand further nature complexes, we attempted to identify proteins that interact with enzyme We identified WDR20, a WD40-repeat containing protein, as common binding partner UAF1, Further analysis showed WDR20 associates exclusively...

The 13 Fanconi anemia (FA) proteins cooperate in a common DNA repair pathway. Eight of these are assembled into multisubunit E3 ligase called the FA core complex. During S phase, complex is loaded by FANCM protein chromatin where it monoubiquitinates its substrates. In mitosis, released from an unknown mechanism. Here we show that hyperphosphorylated and degraded during mitosis. β-TRCP Plk1 key regulators degradation. Nondegradable mutant forms retain disrupt Our data provide novel mechanism...

The Fanconi anemia pathway is required for repair of DNA interstrand cross-links (ICL). pathway-deficient cells are hypersensitive to ICL-inducing drugs such as cisplatin. Conversely, hyperactivation the a mechanism that may underlie cellular resistance ICL agents. Modulating FANCD2 monoubiquitination, key step in pathway, be an effective therapeutic approach conferring sensitivity Here, we show inhibition Nedd8 conjugation system increases Mechanistically, inhibition, either by...

Significance The BMI1-containing Polycomb Repressive Complex is an important gene silencer during development, stem cell maintenance, and cancer progression. BMI1 also involved in DNA damage response, but its downstream mechanism unclear. Here we identified UBR5 as a factor whose chromatin recruitment regulated by BMI1. We showed that repress the RNA polymerase II (Pol II) elongation nascent synthesis at UV-induced lesions. associates with regulates abundance of histone chaperon complex FACT...

Homologous recombination (HR) is critical for error-free repair of DNA double-strand breaks. Chromatin loading RAD51, a key protein that mediates the recombination, crucial step in execution HR repair. Here, we present evidence SUMOylation RAD51 recruitment to chromatin and We found topoisomerase 1-binding arginine/serine-rich (TOPORS) induces at lysine residues 57 70 response damaging agents. The was facilitated by an ATM-induced phosphorylation TOPORS threonine 515 upon damage. Knockdown...

Ubiquitinated integral membrane proteins are delivered to the interior of lysosome/vacuole for degradation. This process relies on specific ubiquitination potential cargo and recognition that Ub-cargo by sorting receptors at multiple compartments. We show endosomal Hse1-Vps27 receptor binds ubiquitin peptidases ligase Rsp5. Hse1 is linked Rsp5 directly via a PY element within its C-terminus through novel protein Hua1, which recruits complex Rsp5, Rup1, Ubp2. The SH3 domain also...

Protein neddylation is involved in a wide variety of cellular processes. Here we show that the DNA damage response perturbed cells inactivated with an E2 Nedd8 conjugating enzyme UBE2M, measured by RAD51 foci formation kinetics and cell based repair assays. UBE2M knockdown increases breakages sensitivity to damaging agents, further suggesting heightened genomic instability defective activity. Investigating downstream Cullin targets revealed silencing 1, 2, 4 ligases incurred significant...

USP1 deubiquitinating enzyme and its stoichiometric binding partner UAF1 play an essential role in promoting DNA homologous recombination (HR) repair response to various types of damaging agents. Deubiquitination FANCD2 may be attributed the key USP1-UAF1 complex regulating HR repair, however whether promotes independently deubiquitination is not known. Here we show evidence that has a FANCD2-independent function repair. Proteomic search UAF1-interacting proteins revealed associates with...

Proteasome-dependent processing of the endoplasmic reticulum localized transcription factor Spt23p Saccharomyces cerevisiae generates its transcriptionally competent form and requires WW domain containing Rsp5p ubiquitin ligase. Although previous studies documented an Rsp5p-Spt23p association in cells, very little is known about nature this interaction. We report here identification imperfect type I domain-binding site (LPKY) within carboxyl-terminal region that required for binding vitro...

Fanconi anemia (FA) is a genome instability syndrome characterized by bone marrow failure and cellular hypersensitivity to DNA cross-linking agents. In response damage, the FA pathway activated through cooperation of 16 proteins. A central player in multisubunit E3 ubiquitin ligase complex or core complex, which monoubiquitinates its substrates FANCD2 FANCI. FANCE, subunit plays an essential role promoting integrity directly recognizing FANCD2. To delineate substrate ubiquitination from...

Common fragile sites (CFSs) are breakage-prone genomic loci, and considered to be hotspots for rearrangements frequently observed in cancers. Understanding the underlying mechanisms CFS instability will lead better insight on cancer etiology. Here we show that Polycomb group proteins BMI1 RNF2 suppressors of transcription-replication conflicts (TRCs) instability. Cells depleted or showed slower replication forks elevated fork stalling. These phenotypes associated with increase occupancy RNA...

The cell cycle apoptosis regulator (CCAR) family of proteins consists two proteins, CCAR1 and CCAR2, that play a variety roles in cellular physiology pathology. These multidomain are able to perform multiple interactions functions, playing processes such as stress responses, metabolism, the DNA damage response. evolutionary conservation CCAR allows their study model organisms Caenorhabditis elegans, where role for aging was revealed. This review particularly highlights multifaceted...

The subtidal red alga Plocamium cartilagineum was collected from the Western Antarctic Peninsula during 2011 and 2017 austral summers. Bulk collections specific sites corresponded to chemogroups identified by Young et al. in 2013. One of yielded several known acyclic halogenated monoterpenes (2-5) as well undescribed compounds same class, anverenes B-D (6-8). Examination another chemogroup an cyclic monoterpene anverene E (9) its major secondary metabolite. Elucidation structures achieved...

Abstract Human CtIP maintains genomic integrity primarily by promoting 5′ DNA end resection, an initial step of the homologous recombination (HR). A few mechanisms have been suggested as to how recruitment damage sites is controlled, but it likely that we do not yet full understanding process. Here, provide evidence and functioning are controlled SIAH2 E3 ubiquitin ligase. We found interacts ubiquitinates at its N-terminal lysine residues. Mutating key residues impaired DSBs stalled...

Abstract Mechanisms underlying the pathogenesis of high-grade serous epithelial ovarian cancers (HGSOC) are not yet well defined although key precursor cells have been identified (including fimbriated fallopian tube epithelium, FTSECs). Since iron is elevated in endometriotic cysts and pelvic cavity, it suggested that this source redox-active may contribute to cancer pathogenesis. Specifically, sources nontransferrin-bound (NTBI) within cavity could arise from ovulation, retrograde...