03419nas a2200253   4500008004100000022001400041245011200055210006900167260000900236300000800245490000700253520257000260100002502830700003202855700001602887700001702903700002102920700002502941700002202966700001802988700002203006700001803028856011903046       2012                        eng d  a1471-216400aIdentification of yeast genes that confer resistance to chitosan oligosaccharide (COS) using chemogenomics.0 aIdentification of yeast genes that confer resistance to chitosan  c2012  a2670 v133 aBACKGROUND: Chitosan oligosaccharide (COS), a deacetylated derivative of chitin, is an abundant, and renewable natural polymer. COS has higher antimicrobial properties than chitosan and is presumed to act by disrupting/permeabilizing the cell membranes of bacteria, yeast and fungi. COS is relatively non-toxic to mammals. By identifying the molecular and genetic targets of COS, we hope to gain a better understanding of the antifungal mode of action of COS. RESULTS: Three different chemogenomic fitness assays, haploinsufficiency (HIP), homozygous deletion (HOP), and multicopy suppression (MSP) profiling were combined with a transcriptomic analysis to gain insight in to the mode of action and mechanisms of resistance to chitosan oligosaccharides. The fitness assays identified 39 yeast deletion strains sensitive to COS and 21 suppressors of COS sensitivity. The genes identified are involved in processes such as RNA biology (transcription, translation and regulatory mechanisms), membrane functions (e.g. signalling, transport and targeting), membrane structural components, cell division, and proteasome processes. The transcriptomes of control wild type and 5 suppressor strains overexpressing ARL1, BCK2, ERG24, MSG5, or RBA50, were analyzed in the presence and absence of COS. Some of the up-regulated transcripts in the suppressor overexpressing strains exposed to COS included genes involved in transcription, cell cycle, stress response and the Ras signal transduction pathway. Down-regulated transcripts included those encoding protein folding components and respiratory chain proteins. The COS-induced transcriptional response is distinct from previously described environmental stress responses (i.e. thermal, salt, osmotic and oxidative stress) and pre-treatment with these well characterized environmental stressors provided little or any resistance to COS. CONCLUSIONS: Overexpression of the ARL1 gene, a member of the Ras superfamily that regulates membrane trafficking, provides protection against COS-induced cell membrane permeability and damage. We found that the ARL1 COS-resistant over-expression strain was as sensitive to Amphotericin B, Fluconazole and Terbinafine as the wild type cells and that when COS and Fluconazole are used in combination they act in a synergistic fashion. The gene targets of COS identified in this study indicate that COS’s mechanism of action is different from other commonly studied fungicides that target membranes, suggesting that COS may be an effective fungicide for drug-resistant fungal pathogens.1 aJaime, María, D L A1 aLopez-Llorca, Luis, Vicente1 aConesa, Ana1 aLee, Anna, Y1 aProctor, Michael1 aHeisler, Lawrence, E1 aGebbia, Marinella1 aGiaever, Guri1 aWestwood, Timothy1 aNislow, Corey  uhttps://clinbioinfosspa.es/content/identification-yeast-genes-confer-resistance-chitosan-oligosaccharide-cos-using01700nas a2200265   4500008004100000245004500041210004400086260000900130300001300139490000600152520096600158653000801124653001401132100002001146700001601166700002701182700002001209700002001229700002301249700001901272700001901291700002001310700002001330856008401350       2010                        eng d00aInitial genomics of the human nucleolus.0 aInitial genomics of the human nucleolus  c2010  ae10008890 v63 a<p>We report for the first time the genomics of a nuclear compartment of the eukaryotic cell. 454 sequencing and microarray analysis revealed the pattern of nucleolus-associated chromatin domains (NADs) in the linear human genome and identified different gene families and certain satellite repeats as the major building blocks of NADs, which constitute about 4% of the genome. Bioinformatic evaluation showed that NAD-localized genes take part in specific biological processes, like the response to other organisms, odor perception, and tissue development. 3D FISH and immunofluorescence experiments illustrated the spatial distribution of NAD-specific chromatin within interphase nuclei and its alteration upon transcriptional changes. Altogether, our findings describe the nature of DNA sequences associated with the human nucleolus and provide insights into the function of the nucleolus in genome organization and establishment of nuclear architecture.</p>10aNGS10anucleolus1 aNémeth, Attila1 aConesa, Ana1 aSantoyo-López, Javier1 aMedina, Ignacio1 aMontaner, David1 aPéterfia, Bálint1 aSolovei, Irina1 aCremer, Thomas1 aDopazo, Joaquin1 aLängst, Gernot  uhttp://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1000889