Poly(ADP-ribosyl)ation is a reversible post-translational modification synthetized by ADP-ribose transferases and removed by poly(ADP-ribose) glycohydrolase (PARG), which plays important roles in DNA damage repair. While well-studied in somatic tissues, much less is known about poly(ADP-ribosyl)ation in the germline, where DNA double-strand breaks are introduced by a regulated program and repaired by crossover recombination to establish a tether between homologous chromosomes. The interaction between the parental chromosomes is facilitated by meiotic specific adaptation of the chromosome axes and cohesins, and reinforced by the synaptonemal complex. Here, we uncover an unexpected role for PARG in coordinating the induction of meiotic DNA breaks and their homologous recombination-mediated repair in Caenorhabditis elegans. PARG-1/PARG interacts with both axial and central elements of the synaptonemal complex, REC-8/Rec8 and the MRN/X complex. PARG-1 shapes the recombination landscape and reinforces the tightly regulated control of crossover numbers without requiring its catalytic activity. We unravel roles in regulating meiosis, beyond its enzymatic activity in poly(ADP-ribose) catabolism.

• MeSH
• buněčné jádro metabolismus   MeSH
• Caenorhabditis elegans genetika   metabolismus   MeSH
• DNA metabolismus   MeSH
• dvouřetězcové zlomy DNA * MeSH
• glykosidhydrolasy genetika   metabolismus   MeSH
• jaderné proteiny genetika   metabolismus   MeSH
• oprava DNA fyziologie   MeSH
• poly-ADP-ribosylace MeSH
• polyadenosindifosfátribosa metabolismus   MeSH
• posttranslační úpravy proteinů MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• zárodečné buňky MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Fanconi Anemia is a rare genetic disease associated with DNA repair defects, congenital abnormalities and infertility. Most of FA pathway is evolutionary conserved, allowing dissection and mechanistic studies in simpler model systems such as Caenorhabditis elegans. In the present study, we employed C. elegans to better understand the role of FA group D2 (FANCD2) protein in vivo, a key player in promoting genome stability. We report that localization of FCD-2/FANCD2 is dynamic during meiotic prophase I and requires its heterodimeric partner FNCI-1/FANCI. Strikingly, we found that FCD-2 recruitment depends on SPO-11-induced double-strand breaks (DSBs) but not RAD-51-mediated strand invasion. Furthermore, exposure to DNA damage-inducing agents boosts FCD-2 recruitment on the chromatin. Finally, analysis of genetic interaction between FCD-2 and BRC-1 (the C. elegans orthologue of mammalian BRCA1) supports a role for these proteins in different DSB repair pathways. Collectively, we showed a direct involvement of FCD-2 at DSBs and speculate on its function in driving meiotic DNA repair.

• MeSH
• Caenorhabditis elegans genetika   růst a vývoj   metabolismus   MeSH
• dvouřetězcové zlomy DNA * MeSH
• meióza * MeSH
• oprava DNA * MeSH
• protein FANCD2 genetika   metabolismus   MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• rekombinace genetická * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Parasitic nematodes transition between dramatically different free-living and parasitic stages, with correctly timed development and migration crucial to successful completion of their lifecycle. However little is known of the mechanisms controlling these transitions. microRNAs (miRNAs) negatively regulate gene expression post-transcriptionally and regulate development of diverse organisms. Here we used microarrays to determine the expression profile of miRNAs through development and in gut tissue of the pathogenic nematode Haemonchus contortus. Two miRNAs, mir-228 and mir-235, were enriched in infective L3 larvae, an arrested stage analogous to Caenorhabditis elegans dauer larvae. We hypothesized that these miRNAs may suppress development and maintain arrest. Consistent with this, inhibitors of these miRNAs promoted H. contortus development from L3 to L4 stage, while genetic deletion of C. elegans homologous miRNAs reduced dauer arrest. Epistasis studies with C. elegans daf-2 mutants showed that mir-228 and mir-235 synergise with FOXO transcription factor DAF-16 in the insulin signaling pathway. Target prediction suggests that these miRNAs suppress metabolic and transcription factor activity required for development. Our results provide novel insight into the expression and functions of specific miRNAs in regulating nematode development and identify miRNAs and their target genes as potential therapeutic targets to limit parasite survival within the host.

• MeSH
• Caenorhabditis elegans genetika   MeSH
• cholesteny farmakologie   MeSH
• delece genu MeSH
• druhová specificita MeSH
• genová ontologie MeSH
• Haemonchus účinky léků   genetika   růst a vývoj   MeSH
• larva MeSH
• messenger RNA genetika   metabolismus   MeSH
• mikro RNA biosyntéza   genetika   MeSH
• proteiny Caenorhabditis elegans genetika   MeSH
• receptor inzulinu genetika   MeSH
• RNA helmintů biosyntéza   genetika   MeSH
• vývojová regulace genové exprese účinky léků   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Cytokinins are phytohormones that are involved in many processes in plants, including growth, differentiation and leaf senescence. However, they also have various activities in animals. For example, kinetin and trans-zeatin can reduce levels of several aging markers in human fibroblasts. Kinetin can also protect mice against oxidative and glyoxidative stress, and prolong fruit flies' lifespan. Additionally, several cytokinins are currently used in cosmetics. To extend knowledge of the breadth of cytokinins' activities, we examined effects of natural cytokinin bases on the model nematode Caenorhabditis elegans. We found that kinetin, para-topolin and meta-topolin prolonged the lifespan of C. elegans. Kinetin also protected the organism against oxidative and heat stress. Furthermore, our results suggest that presence of reactive oxygen species, but not DAF-16 (the main effector of the insulin/insulin-like growth factor signaling pathway), is required for the beneficial effects of kinetin. Ultra-high performance liquid chromatography-tandem mass spectrometric analysis showed that kinetin is unlikely to occur naturally in C. elegans, but the worm efficiently absorbs and metabolizes it into kinetin riboside and kinetin riboside-5'-monophosphate.

• MeSH
• Caenorhabditis elegans účinky léků   genetika   fyziologie   MeSH
• cytokininy farmakokinetika   farmakologie   MeSH
• dlouhověkost účinky léků   fyziologie   MeSH
• forkhead transkripční faktory genetika   metabolismus   MeSH
• inzulin metabolismus   MeSH
• kinetin farmakokinetika   farmakologie   MeSH
• mutace MeSH
• oxidační stres účinky léků   MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• reakce na tepelný šok účinky léků   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• regulátory růstu rostlin farmakokinetika   farmakologie   MeSH
• signální transdukce účinky léků   MeSH
• termotolerance účinky léků   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Van Gogh-like (Vangl) and Prickle (Pk) are core components of the non-canonical Wnt planar cell polarity pathway that controls epithelial polarity and cell migration. Studies in vertebrate model systems have suggested that Vangl and Pk may also inhibit signaling through the canonical Wnt/β-catenin pathway, but the functional significance of this potential cross-talk is unclear. In the nematode C. elegans, the Q neuroblasts and their descendants migrate in opposite directions along the anteroposterior body axis. The direction of these migrations is specified by Wnt signaling, with activation of canonical Wnt signaling driving posterior migration, and non-canonical Wnt signaling anterior migration. Here, we show that the Vangl ortholog VANG-1 influences the Wnt signaling response of the Q neuroblasts by negatively regulating canonical Wnt signaling. This inhibitory activity depends on a carboxy-terminal PDZ binding motif in VANG-1 and the Dishevelled ortholog MIG-5, but is independent of the Pk ortholog PRKL-1. Moreover, using Vangl1 and Vangl2 double mutant cells, we show that a similar mechanism acts in mammalian cells. We conclude that cross-talk between VANG-1/Vangl and the canonical Wnt pathway is an evolutionarily conserved mechanism that ensures robust specification of Wnt signaling responses.

• MeSH
• beta-katenin genetika   metabolismus   MeSH
• buněčný rodokmen MeSH
• Caenorhabditis elegans cytologie   genetika   metabolismus   MeSH
• fosfoproteiny genetika   metabolismus   MeSH
• geneticky modifikovaná zvířata MeSH
• geny helmintů MeSH
• homeodoménové proteiny genetika   metabolismus   MeSH
• intracelulární signální peptidy a proteiny genetika   metabolismus   MeSH
• mutace MeSH
• nervové kmenové buňky cytologie   metabolismus   MeSH
• polarita buněk genetika   fyziologie   MeSH
• protein dishevelled genetika   metabolismus   MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• rozvržení tělního plánu genetika   fyziologie   MeSH
• signální dráha Wnt genetika   fyziologie   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

One of the most studied phosphoinositides is phosphatidylinositol 4,5-bisphosphate (PIP2), which localizes to the plasma membrane, nuclear speckles, small foci in the nucleoplasm, and to the nucleolus in mammalian cells. Here, we show that PIP2 also localizes to the nucleus in prophase I, during the gametogenesis of C. elegans hermaphrodite. The depletion of PIP2 by type I PIP kinase (PPK-1) kinase RNA interference results in an altered chromosome structure and leads to various defects during meiotic progression. We observed a decreased brood size and aneuploidy in progeny, defects in synapsis, and crossover formation. The altered chromosome structure is reflected in the increased transcription activity of a tightly regulated process in prophase I. To elucidate the involvement of PIP2 in the processes during the C. elegans development, we identified the PIP2-binding partners, leucine-rich repeat (LRR-1) protein and proteasome subunit beta 4 (PBS-4), pointing to its involvement in the ubiquitin⁻proteasome pathway.

• MeSH
• buněčné jádro metabolismus   MeSH
• Caenorhabditis elegans genetika   růst a vývoj   metabolismus   MeSH
• chromozomy chemie   MeSH
• fosfatidylinositol-4,5-difosfát metabolismus   MeSH
• fosfotransferasy s alkoholovou skupinou jako akceptorem genetika   MeSH
• gametogeneze * MeSH
• hermafroditické organismy genetika   růst a vývoj   metabolismus   MeSH
• profáze meiózy I MeSH
• proteasomový endopeptidasový komplex metabolismus   MeSH
• proteiny Caenorhabditis elegans genetika   MeSH
• proteiny metabolismus   MeSH
• RNA interference MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

ALKB-8 is a 2-oxoglutarate-dependent dioxygenase homologous to bacterial AlkB, which oxidatively demethylates DNA substrates. The mammalian AlkB family contains AlkB homologues denominated ALKBH1 to 8 and FTO. The C. elegans genome includes five AlkB-related genes, homologues of ALKBH1, 4, 6, 7, and 8, but lacks homologues of ALKBH2, 3, and 5 and FTO. ALKBH8 orthologues differ from other AlkB family members by possessing an additional methyltransferase module and an RNA binding N-terminal module. The ALKBH8 methyltransferase domain generates the wobble nucleoside 5-methoxycarbonylmethyluridine from its precursor 5-carboxymethyluridine and its (R)- and (S)-5-methoxycarbonylhydroxymethyluridine hydroxylated forms in tRNA Arg/UCG and tRNA Gly/UCC. The ALKBH8/ALKB-8 methyltransferase domain is highly similar to yeast TRM9, which selectively modulates translation of mRNAs enriched with AGA and GAA codons under both normal and stress conditions. In this report, we studied the role of alkb-8 in C. elegans. We show that downregulation of alkb-8 increases detection of lysosome-related organelles visualized by Nile red in vivo. Reversely, forced expression of alkb-8 strongly decreases the detection of this compartment. In addition, overexpression of alkb-8 applied in a pulse during the L1 larval stage increases the C. elegans lifespan.

• MeSH
• Caenorhabditis elegans embryologie   enzymologie   genetika   MeSH
• dioxygenasy metabolismus   MeSH
• dlouhověkost MeSH
• down regulace genetika   MeSH
• embryo nesavčí metabolismus   MeSH
• geneticky modifikovaná zvířata MeSH
• kyseliny ketoglutarové metabolismus   MeSH
• larva metabolismus   MeSH
• lyzozomy metabolismus   MeSH
• methyltransferasy metabolismus   MeSH
• operon MeSH
• promotorové oblasti (genetika) MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• RNA interference MeSH
• S-adenosylmethionin metabolismus   MeSH
• stárnutí metabolismus   MeSH
• vývojová regulace genové exprese MeSH
• zelené fluorescenční proteiny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Central to homologous recombination in eukaryotes is the RAD51 recombinase, which forms helical nucleoprotein filaments on single-stranded DNA (ssDNA) and catalyzes strand invasion with homologous duplex DNA. Various regulatory proteins assist this reaction including the RAD51 paralogs. We recently discovered that a RAD51 paralog complex from C. elegans, RFS-1/RIP-1, functions predominantly downstream of filament assembly by binding and remodeling RAD-51-ssDNA filaments to a conformation more proficient for strand exchange. Here, we demonstrate that RFS-1/RIP-1 acts by shutting down RAD-51 dissociation from ssDNA. Using stopped-flow experiments, we show that RFS-1/RIP-1 confers this dramatic stabilization by capping the 5' end of RAD-51-ssDNA filaments. Filament end capping propagates a stabilizing effect with a 5'→3' polarity approximately 40 nucleotides along individual filaments. Finally, we discover that filament capping and stabilization are dependent on nucleotide binding, but not hydrolysis by RFS-1/RIP-1. These data define the mechanism of RAD51 filament remodeling by RAD51 paralogs.

• MeSH
• DNA vazebné proteiny genetika   metabolismus   MeSH
• intermediární filamenta genetika   metabolismus   MeSH
• jednovláknová DNA genetika   MeSH
• multiproteinové komplexy metabolismus   MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• rekombinační oprava DNA MeSH
• rekombinasa Rad51 genetika   metabolismus   MeSH
• transportní proteiny genetika   metabolismus   MeSH
• vazba proteinů MeSH
• Publikační typ
• časopisecké články MeSH

The prorenin receptor (ATP6AP2) is a multifunctional transmembrane protein; it is a constituent of proton-translocating V-ATPase, a non-proteolytic activator of renin and an adaptor in the Wnt/β-catenin pathway. Here, we studied vha-20, one of the two prorenin receptor homologues that are identified by sequence similarity in the C. elegans genome. We show that vha-20 (R03E1.2) is prominently expressed in the intestine, in the excretory cell and in amphid neurons, tissues critical for regulation of ion and water management. The expression of vha-20 in the intestine is dependent on NHR-31, a nuclear receptor related to HNF4. VHA-20 is indispensable for normal larval development, acidification of the intestine, and is required for nutrient uptake. Inhibition of vha-20 by RNAi leads to complex deterioration of water and pH gradients at the level of the whole organism including distention of pseudocoelome cavity. This suggests new roles of prorenin receptor in the regulation of body ion and water management and in acidification of intestinal lumen in nematodes.

• MeSH
• Caenorhabditis elegans fyziologie   MeSH
• homeostáza fyziologie   MeSH
• koncentrace vodíkových iontů MeSH
• larva fyziologie   MeSH
• polymerázová řetězová reakce MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• stanovení celkové genové exprese MeSH
• transkriptom MeSH
• vakuolární protonové ATPasy genetika   metabolismus   MeSH
• voda metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Repair of DNA double strand breaks by homologous recombination (HR) is initiated by Rad51 filament nucleation on single-stranded DNA (ssDNA), which catalyzes strand exchange with homologous duplex DNA. BRCA2 and the Rad51 paralogs are tumor suppressors and critical mediators of Rad51. To gain insight into Rad51 paralog function, we investigated a heterodimeric Rad51 paralog complex, RFS-1/RIP-1, and uncovered the molecular basis by which Rad51 paralogs promote HR. Unlike BRCA2, which nucleates RAD-51-ssDNA filaments, RFS-1/RIP-1 binds and remodels pre-synaptic filaments to a stabilized, "open," and flexible conformation, in which the ssDNA is more accessible to nuclease digestion and RAD-51 dissociation rate is reduced. Walker box mutations in RFS-1, which abolish filament remodeling, fail to stimulate RAD-51 strand exchange activity, demonstrating that remodeling is essential for RFS-1/RIP-1 function. We propose that Rad51 paralogs stimulate HR by remodeling the Rad51 filament, priming it for strand exchange with the template duplex.

• MeSH
• Caenorhabditis elegans metabolismus   MeSH
• DNA vazebné proteiny genetika   metabolismus   MeSH
• HEK293 buňky MeSH
• homologní rekombinace * MeSH
• jednovláknová DNA metabolismus   MeSH
• komplex proteinů jaderného póru metabolismus   MeSH
• lidé MeSH
• mutace MeSH
• proteiny Caenorhabditis elegans genetika   metabolismus   MeSH
• rekombinasa Rad51 metabolismus   MeSH
• Saccharomyces cerevisiae - proteiny metabolismus   MeSH
• Saccharomyces cerevisiae metabolismus   MeSH
• transportní proteiny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH