Oxidative stress is associated with cardiovascular and neurodegenerative diseases, diabetes, cancer, psychiatric disorders and aging. In order to counteract, eliminate and/or adapt to the sources of stress, cells possess elaborate stress-response mechanisms, which also operate at the level of regulating transcription. Interestingly, it is becoming apparent that the metabolic state of the cell and certain metabolites can directly control the epigenetic information and gene expression. In the fission yeast Schizosaccharomyces pombe, the conserved Sty1 stress-activated protein kinase cascade is the main pathway responding to most types of stresses, and regulates the transcription of hundreds of genes via the Atf1 transcription factor. Here we report that fission yeast cells defective in fatty acid synthesis (cbf11, mga2 and ACC/cut6 mutants; FAS inhibition) show increased expression of a subset of stress-response genes. This altered gene expression depends on Sty1-Atf1, the Pap1 transcription factor, and the Gcn5 and Mst1 histone acetyltransferases, is associated with increased acetylation of histone H3 at lysine 9 in the corresponding gene promoters, and results in increased cellular resistance to oxidative stress. We propose that changes in lipid metabolism can regulate the chromatin and transcription of specific stress-response genes, which in turn might help cells to maintain redox homeostasis.

• MeSH
• acetyltransferasy genetika   MeSH
• chromatin * metabolismus   MeSH
• exprese genu MeSH
• fosforylace MeSH
• metabolismus lipidů * MeSH
• mitogenem aktivované proteinkinasy metabolismus   MeSH
• oxidační stres * MeSH
• regulace genové exprese u hub MeSH
• Schizosaccharomyces pombe - proteiny * genetika   MeSH
• Schizosaccharomyces * genetika   MeSH
• transkripční faktory bZIP genetika   MeSH
• transkripční faktory genetika   MeSH
• Publikační typ
• časopisecké články MeSH

Although human nucleoporin Tpr is frequently deregulated in cancer, its roles are poorly understood. Here we show that Tpr depletion generates transcription-dependent replication stress, DNA breaks, and genomic instability. DNA fiber assays and electron microscopy visualization of replication intermediates show that Tpr deficient cells exhibit slow and asymmetric replication forks under replication stress. Tpr deficiency evokes enhanced levels of DNA-RNA hybrids. Additionally, complementary proteomic strategies identify a network of Tpr-interacting proteins mediating RNA processing, such as MATR3 and SUGP2, and functional experiments confirm that their depletion trigger cellular phenotypes shared with Tpr deficiency. Mechanistic studies reveal the interplay of Tpr with GANP, a component of the TREX-2 complex. The Tpr-GANP interaction is supported by their shared protein level alterations in a cohort of ovarian carcinomas. Our results reveal links between nucleoporins, DNA transcription and replication, and the existence of a network physically connecting replication forks with transcription, splicing, and mRNA export machinery.

• MeSH
• acetyltransferasy genetika   metabolismus   MeSH
• HeLa buňky MeSH
• intracelulární signální peptidy a proteiny genetika   metabolismus   MeSH
• komplex proteinů jaderného póru genetika   metabolismus   MeSH
• lidé MeSH
• mapy interakcí proteinů MeSH
• nádory genetika   MeSH
• nestabilita genomu MeSH
• poškození DNA MeSH
• protoonkogenní proteiny genetika   metabolismus   MeSH
• replikace DNA * MeSH
• transport RNA MeSH
• viabilita buněk MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The most recent genome-editing system called CRISPR-Cas9 (clustered regularly interspaced short palindromic repeat system with associated protein 9-nuclease) was employed to delete four non-essential genes (i.e., Caeco1, Caidh1, Carom2, and Cataf10) individually to establish their gene functionality annotations in pathogen Candida albicans. The biological roles of these genes were investigated with respect to the cell wall integrity and biogenesis, calcium/calcineurin pathways, susceptibility of mutants towards temperature, drugs and salts. All the mutants showed increased vulnerability compared to the wild-type background strain towards the cell wall-perturbing agents, (antifungal) drugs and salts. All the mutants also exhibited repressed and defective hyphal growth and smaller colony size than control CA14. The cell cycle of all the mutants decreased enormously except for those with Carom2 deletion. The budding index and budding size also increased for all mutants with altered bud shape. The disposition of the mutants towards cell wall-perturbing enzymes disclosed lower survival and more rapid cell wall lysis events than in wild types. The pathogenicity and virulence of the mutants was checked by adhesion assay, and strains lacking rom2 and eco1 were found to possess the least adhesion capacity, which is synonymous to their decreased pathogenicity and virulence.

• MeSH
• acetyltransferasy nedostatek   genetika   fyziologie   MeSH
• antifungální látky farmakologie   MeSH
• buněčná adheze MeSH
• buněčná stěna účinky léků   MeSH
• buněčný cyklus MeSH
• Candida albicans účinky léků   genetika   patogenita   fyziologie   MeSH
• chitinasy farmakologie   MeSH
• CRISPR-Cas systémy MeSH
• delece genu MeSH
• endo-1,3-beta-glukanasa farmakologie   MeSH
• faktory asociované s proteinem vázajícím TATA box nedostatek   genetika   fyziologie   MeSH
• fungální proteiny genetika   fyziologie   MeSH
• geny hub * MeSH
• hyfy růst a vývoj   MeSH
• isocitrátdehydrogenasa nedostatek   genetika   fyziologie   MeSH
• kationty farmakologie   MeSH
• nepohlavní rozmnožování MeSH
• otevřené čtecí rámce MeSH
• poškození DNA MeSH
• vápník fyziologie   MeSH
• virulence genetika   MeSH
• Publikační typ
• časopisecké články MeSH

Viruses have evolved mechanisms to manipulate microtubules (MTs) for the efficient realization of their replication programs. Studying the mechanisms of replication of mouse polyomavirus (MPyV), we observed previously that in the late phase of infection, a considerable amount of the main structural protein, VP1, remains in the cytoplasm associated with hyperacetylated microtubules. VP1-microtubule interactions resulted in blocking the cell cycle in the G2/M phase. We are interested in the mechanism leading to microtubule hyperacetylation and stabilization and the roles of tubulin acetyltransferase 1 (αTAT1) and deacetylase histone deacetylase 6 (HDAC6) and VP1 in this mechanism. Therefore, HDAC6 inhibition assays, αTAT1 knock out cell infections, in situ cell fractionation, and confocal and TIRF microscopy were used. The experiments revealed that the direct interaction of isolated microtubules and VP1 results in MT stabilization and a restriction of their dynamics. VP1 leads to an increase in polymerized tubulin in cells, thus favoring αTAT1 activity. The acetylation status of MTs did not affect MPyV infection. However, the stabilization of MTs by VP1 in the late phase of infection may compensate for the previously described cytoskeleton destabilization by MPyV early gene products and is important for the observed inhibition of the G2→M transition of infected cells to prolong the S phase.

• MeSH
• acetylace MeSH
• acetyltransferasy genetika   metabolismus   MeSH
• buněčné linie MeSH
• buněčný cyklus MeSH
• cytoplazma metabolismus   MeSH
• fibroblasty virologie   MeSH
• histondeacetylasa 6 genetika   metabolismus   MeSH
• interakce mikroorganismu a hostitele * MeSH
• mikrotubuly metabolismus   virologie   MeSH
• myši MeSH
• Polyomavirus genetika   metabolismus   MeSH
• posttranslační úpravy proteinů MeSH
• tubulin metabolismus   MeSH
• virové plášťové proteiny genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: The aac(6')-Ih gene encoding aminoglycoside 6'-N-acetyltransferase type I subtype h [AAC(6')-Ih] is plasmid-borne in Acinetobacter baumannii where it confers high-level amikacin resistance, but its origin remains unknown. We searched for the gene in the genomes of a collection of 133 Acinetobacter spp. and studied its species specificity, expression and dissemination. METHODS: Gene copy number was determined by quantitative PCR, expression by quantitative RT-PCR, MIC by microdilution and transfer by plasmid mobilization. RESULTS: The aac(6')-Ih gene was present in the chromosome of the two Acinetobacter gyllenbergii of the collection and was detected in all seven A. gyllenbergii clinical isolates. They had indistinguishable flanking regions indicating that the gene was intrinsic to this species. A. baumannii PIS Aba23 promoters were provided by insertion of ISAba23, which disrupted the Pnative promoter in A. gyllenbergii. Both types of promoters were similarly potent in Escherichia coli and A. baumannii. Aminoglycoside MICs for A. baumannii harbouring pIP1858 were higher than for A. gyllenbergii due to gene dosage. The non-self-transferable plasmid could be mobilized to other A. baumannii cells by the broad host range plasmid RP4. CONCLUSIONS: We have found the origin of aac(6')-Ih in A. gyllenbergii, a species isolated, although rarely, in humans, and documented that dissemination of this gene is restricted to the Acinetobacter genus.

• MeSH
• acetyltransferasy genetika   metabolismus   MeSH
• Acinetobacter baumannii klasifikace   účinky léků   enzymologie   genetika   MeSH
• aminoglykosidy metabolismus   farmakologie   MeSH
• antibakteriální látky metabolismus   farmakologie   MeSH
• bakteriální léková rezistence * MeSH
• genová dávka MeSH
• infekce bakteriemi rodu Acinetobacter mikrobiologie   MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• plazmidy analýza   MeSH
• přenos genů horizontální MeSH
• promotorové oblasti (genetika) MeSH
• transpozibilní elementy DNA MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

The human dopamine, norepinephrine, and serotonin transporters (hDAT, hNET, and hSERT) are carriers of neurotransmitters and targets for many drugs. Pioneering works in the past three years to elucidate experimental models of the Drosophila dDAT and human hSERT structures will rapidly impact the field of neuroscience. Here, we evaluated automated homology-based human models of these transporters, employing systematic physics-based, knowledge-based, and empirical-based check. Modeling guidelines were conveyed with attention to the central binding site (S1), secondary binding site (S2), and the extracellular loops EL2 and EL4. Application of new experimental models (dDAT and hSERT) will improve the accuracy of homology models, previously utilizing prokaryotic leucine transporter (LeuT) structure, and provide better predictions of ligand interactions, which is required for understanding of cellular mechanisms and for development of novel therapeutics.

• MeSH
• acetyltransferasy genetika   metabolismus   MeSH
• Drosophila MeSH
• konformace proteinů MeSH
• lidé MeSH
• membránové transportní proteiny pro serotonin genetika   metabolismus   MeSH
• molekulární modely * MeSH
• proteiny Drosophily genetika   metabolismus   MeSH
• proteiny přenášející dopamin přes plazmatickou membránu genetika   metabolismus   MeSH
• proteiny přenášející noradrenalin přes plazmatickou membránu genetika   metabolismus   MeSH
• rozpoznávání automatizované MeSH
• sekvenční homologie aminokyselin * MeSH
• vazebná místa MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH

Acetyl-CoA:α-glucosaminide N-acetyltransferase (N-acetyltransferase) is a lysosomal membrane enzyme that catalyzes a key step in the lysosomal degradation of heparan sulfate. Its deficiency causes Sanfilippo syndrome type IIIC (Mucopolysaccharidosis type IIIC, MPS IIIC). Here we characterize the promoter region of HGSNAT, the gene encoding N-acetyltransferase, which is located in the pericentromeric region of chromosome 8. We show that HGSNAT transcription is driven by a TATA-less promoter whose key elements are contained within the 1054bp region upstream of exon 1. About 400 bases of the region's 3'-prime end overlap with an unmethylated CpG island. Reduced reporter activities from promoter serial deletion constructs suggested strong regulatory elements at positions -101 to -20bp and -1073 to -716bp of the downstream initiation codon (DS-ATG). Targeted mutagenesis of the first Specificity protein 1-A (Sp1-A) of the six in silico-predicted Sp1 sites in the region flanking the major transcription start sites (TSSs, +50/-101) led to a 55% decrease of reporter activity, while inactivation of each of Sp1-B and Sp1-C resulted in its almost two-fold increase. The binding of Sp1 to the region was confirmed by chromatin immunoprecipitation (ChIP). Overall, this confirms that Sp1 is important for regulation of the HGSNAT promoter. Promoter fragments in antisense orientation (constructs pGL4 -20/-1305 and pGL4 +50/-1305) led to reporter activities of about 50% of the pGL4 -1305/-20 activity, implying divergent initiation of transcription at the promoter. We identified two main TSSs at positions +1 and -15 from DS-ATG using Rapid amplification of cDNA ends (5'RACE). Transcripts initiating at the TSSs thus contain only DS-ATG. Five patients from our MPS IIIC cohort (n=23) carried the rs4523300 promoter variant and one the rs149596192 promoter variant. Both variants lowered the expression of the reporter down to 68% and 59%, respectively. However, white blood cell (WBC) N-acetyltransferase activities in individuals carrying the variants did not significantly differ from homozygotes for the wild-type alleles, suggesting only a partial impact of transcriptional regulation on N-acetyltransferase activities in vivo.

• MeSH
• acetyltransferasy genetika   MeSH
• buňky Hep G2 MeSH
• jednonukleotidový polymorfismus * MeSH
• lidé MeSH
• mukopolysacharidóza III genetika   MeSH
• počátek transkripce * MeSH
• studie případů a kontrol MeSH
• TATA box * MeSH
• transkripční faktor Sp1 metabolismus   MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection).

• MeSH
• acetyltransferasy genetika   MeSH
• genom lidský * MeSH
• haplotypy MeSH
• hemoragické horečky virové genetika   MeSH
• jednonukleotidový polymorfismus MeSH
• krevní skupiny - systém Duffy genetika   MeSH
• lidé MeSH
• malárie genetika   MeSH
• MCM komplex, komponenta 6 genetika   MeSH
• meningitida genetika   MeSH
• migrace lidstva * MeSH
• proteiny genetika   MeSH
• receptory buněčného povrchu genetika   MeSH
• receptory spřažené s G-proteiny genetika   MeSH
• selekce (genetika) * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Afrika MeSH

Severe progressive neurological paediatric disease mucopolysaccharidosis III type C is caused by mutations in the HGSNAT gene leading to deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase involved in the lysosomal catabolism of heparan sulphate. To understand the pathophysiology of the disease we generated a mouse model of mucopolysaccharidosis III type C by germline inactivation of the Hgsnat gene. At 6-8 months mice showed hyperactivity, and reduced anxiety. Cognitive memory decline was detected at 10 months and at 12-13 months mice showed signs of unbalanced hesitant walk and urinary retention. Lysosomal accumulation of heparan sulphate was observed in hepatocytes, splenic sinus endothelium, cerebral microglia, liver Kupffer cells, fibroblasts and pericytes. Starting from 5 months, brain neurons showed enlarged, structurally abnormal mitochondria, impaired mitochondrial energy metabolism, and storage of densely packed autofluorescent material, gangliosides, lysozyme, phosphorylated tau, and amyloid-β. Taken together, our data demonstrate for the first time that deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase causes lysosomal accumulation of heparan sulphate in microglial cells followed by their activation and cytokine release. They also show mitochondrial dysfunction in the neurons and neuronal loss explaining why mucopolysaccharidosis III type C manifests primarily as a neurodegenerative disease.

• MeSH
• acetyltransferasy nedostatek   genetika   MeSH
• chování zvířat MeSH
• energetický metabolismus fyziologie   MeSH
• gangliosidy metabolismus   MeSH
• glykosaminoglykany metabolismus   MeSH
• mitochondriální nemoci etiologie   patologie   MeSH
• mukopolysacharidóza III komplikace   patologie   psychologie   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• neuritida etiologie   patologie   MeSH
• neurodegenerativní nemoci etiologie   patologie   psychologie   MeSH
• neurologické vyšetření MeSH
• poruchy proteostázy patologie   MeSH
• proteiny asociované s mikrotubuly metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Mucopolysaccharidosis IIIC (MPS IIIC, or Sanfilippo C syndrome) is a lysosomal storage disorder caused by the inherited deficiency of the lysosomal membrane enzyme acetyl-coenzyme A: alpha -glucosaminide N-acetyltransferase (N-acetyltransferase), which leads to impaired degradation of heparan sulfate. We report the narrowing of the candidate region to a 2.6-cM interval between D8S1051 and D8S1831 and the identification of the transmembrane protein 76 gene (TMEM76), which encodes a 73-kDa protein with predicted multiple transmembrane domains and glycosylation sites, as the gene that causes MPS IIIC when it is mutated. Four nonsense mutations, 3 frameshift mutations due to deletions or a duplication, 6 splice-site mutations, and 14 missense mutations were identified among 30 probands with MPS IIIC. Functional expression of human TMEM76 and the mouse ortholog demonstrates that it is the gene that encodes the lysosomal N-acetyltransferase and suggests that this enzyme belongs to a new structural class of proteins that transport the activated acetyl residues across the cell membrane.

• MeSH
• acetyltransferasy genetika   chemie   metabolismus   MeSH
• buněčné linie MeSH
• exony MeSH
• exprese genu MeSH
• financování organizované MeSH
• klonování DNA MeSH
• komplementární DNA genetika   MeSH
• lidé MeSH
• lidské chromozomy, pár 8 genetika   MeSH
• mapování chromozomů MeSH
• molekulární sekvence - údaje MeSH
• mukopolysacharidóza III enzymologie   genetika   MeSH
• mutace MeSH
• mutační analýza DNA MeSH
• myši MeSH
• polymerázová řetězová reakce MeSH
• rekombinantní fúzní proteiny genetika   metabolismus   MeSH
• rodokmen MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční homologie aminokyselin MeSH
• transfekce MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH