3,179 research outputs found
Molecular evolution of aphids and their primary ( Buchnera sp.) and secondary endosymbionts: implications for the role of symbiosis in insect evolution.
Aphids maintain an obligate, endosymbiotic association with Buchnera sp., a bacterium closely related to Escherichia coli. Bacteria are housed in specialized cells of organ-like structures called bacteriomes in the hemocoel of the aphid and are maternally transmitted. Phylogenetic studies have shown that the association had a single origin, dated about 200-250 million years ago, and that host and endosymbiont lineages have evolved in parallel since then. However, the pattern of deepest branching within the aphid family remains unsolved, which thereby hampers tin appraisal of, for example, the role played by horizontal gene transfer in the early evolution of Buchnera. The main role of Buchnera in this association is the biosynthesis and provisioning of essential amino acids to its aphid host. Physiological and metabolic studies have recently substantiated such nutritional role. In addition, genetic studies of Buchnera from several aphids have shown additional modifications, such as strong genome reduction, high A+T content compared to free-living bacteria, differential evolutionary rates, a relative increase in the number of non-synonymous substitutions, and gene amplification mediated by plasmids. Symbiosis is an active process in insect evolution cis revealed by the intermediate values of the previous characteristics showed by secondary symbionts compared to free-living bacteria and Buchnera
Genome Mutational and Transcriptional Hotspots Are Traps for Duplicated Genes and Sources of Adaptations
[EN] Gene duplication generates new genetic material, which has been shown to lead to major innovations in unicellular and multicellular organisms. A whole-genome duplication occurred in the ancestor of Saccharomyces yeast species but 92% of duplicates returned to single-copy genes shortly after duplication. The persisting duplicated genes in Saccharomyces led to the origin of major metabolic innovations, which have been the source of the unique biotechnological capabilities in the Baker's yeast Saccharomyces cerevisiae. What factors have determined the fate of duplicated genes remains unknown. Here, we report the first demonstration that the local genome mutation and transcription rates determine the fate of duplicates. We show, for the first time, a preferential location of duplicated genes in the mutational and transcriptional hotspots of S. cerevisiae genome. The mechanism of duplication matters, with whole-genome duplicates exhibiting different preservation trends compared to small-scale duplicates. Genome mutational and transcriptional hotspots are rich in duplicates with large repetitive promoter elements. Saccharomyces cerevisiae shows more tolerance to deleterious mutations in duplicates with repetitive promoter elements, which in turn exhibit higher transcriptional plasticity against environmental perturbations. Our data demonstrate that the genome traps duplicates through the accelerated regulatory and functional divergence of their gene copies providing a source of novel adaptations in yeast.This study was supported by a grant (reference: FEDER-BFU2015-66073-P) from the Spanish Ministerio de Economia y Competitividad-FEDER and a grant (reference: ACOMP/2015/026) from the local government Conselleria de Educacion Investigacion, Cultura y Deporte, Generalitat Valenciana to M.A.F. C.T. was supported by a grant Juan de la Cierva from the Spanish Ministerio de Economia y Competitividad (reference: JCA-2012-14056).Fares Riaño, MA.; Sabater-Muñoz, B.; Toft, C. (2017). Genome Mutational and Transcriptional Hotspots Are Traps for Duplicated Genes and Sources of Adaptations. Genome Biology and Evolution. 9(5):1229-1240. https://doi.org/10.1093/gbe/evx085S1229124095Agier, N., & Fischer, G. (2011). The Mutational Profile of the Yeast Genome Is Shaped by Replication. Molecular Biology and Evolution, 29(3), 905-913. doi:10.1093/molbev/msr280Altschul, S. (1997). Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. Nucleic Acids Research, 25(17), 3389-3402. doi:10.1093/nar/25.17.3389Anders, S., & Huber, W. (2010). Differential expression analysis for sequence count data. Genome Biology, 11(10). doi:10.1186/gb-2010-11-10-r106Berry, D. B., & Gasch, A. P. (2008). Stress-activated Genomic Expression Changes Serve a Preparative Role for Impending Stress in Yeast. Molecular Biology of the Cell, 19(11), 4580-4587. doi:10.1091/mbc.e07-07-0680Birchler, J. A., Bhadra, U., Bhadra, M. P., & Auger, D. L. (2001). Dosage-Dependent Gene Regulation in Multicellular Eukaryotes: Implications for Dosage Compensation, Aneuploid Syndromes, and Quantitative Traits. Developmental Biology, 234(2), 275-288. doi:10.1006/dbio.2001.0262Birchler, J. A., Riddle, N. C., Auger, D. L., & Veitia, R. A. (2005). Dosage balance in gene regulation: biological implications. Trends in Genetics, 21(4), 219-226. doi:10.1016/j.tig.2005.02.010Birchler, J. A., & Veitia, R. A. (2012). Gene balance hypothesis: Connecting issues of dosage sensitivity across biological disciplines. Proceedings of the National Academy of Sciences, 109(37), 14746-14753. doi:10.1073/pnas.1207726109Bro, C., Regenberg, B., Lagniel, G., Labarre, J., Montero-LomelĂ, M., & Nielsen, J. (2003). Transcriptional, Proteomic, and Metabolic Responses to Lithium in Galactose-grown Yeast Cells. Journal of Biological Chemistry, 278(34), 32141-32149. doi:10.1074/jbc.m304478200Byrne, K. P. (2005). The Yeast Gene Order Browser: Combining curated homology and syntenic context reveals gene fate in polyploid species. Genome Research, 15(10), 1456-1461. doi:10.1101/gr.3672305Carretero-Paulet, L., & Fares, M. A. (2012). Evolutionary Dynamics and Functional Specialization of Plant Paralogs Formed by Whole and Small-Scale Genome Duplications. Molecular Biology and Evolution, 29(11), 3541-3551. doi:10.1093/molbev/mss162Casamayor, A., Serrano, R., Platara, M., Casado, C., Ruiz, A., & Ariño, J. (2012). The role of the Snf1 kinase in the adaptive response of Saccharomyces cerevisiae to alkaline pH stress. Biochemical Journal, 444(1), 39-49. doi:10.1042/bj20112099Chuang, J. H., & Li, H. (2004). Functional Bias and Spatial Organization of Genes in Mutational Hot and Cold Regions in the Human Genome. PLoS Biology, 2(2), e29. doi:10.1371/journal.pbio.0020029Clark, A. G. (1994). Invasion and maintenance of a gene duplication. Proceedings of the National Academy of Sciences, 91(8), 2950-2954. doi:10.1073/pnas.91.8.2950Conant, G. C., & Wolfe, K. H. (2008). Turning a hobby into a job: How duplicated genes find new functions. Nature Reviews Genetics, 9(12), 938-950. doi:10.1038/nrg2482Costanzo, M., Baryshnikova, A., Bellay, J., Kim, Y., Spear, E. D., Sevier, C. S., … Mostafavi, S. (2010). The Genetic Landscape of a Cell. Science, 327(5964), 425-431. doi:10.1126/science.1180823Deatherage, D. E., & Barrick, J. E. (2014). Identification of Mutations in Laboratory-Evolved Microbes from Next-Generation Sequencing Data Using breseq. Engineering and Analyzing Multicellular Systems, 165-188. doi:10.1007/978-1-4939-0554-6_12Fares, M. A. (2015). The origins of mutational robustness. Trends in Genetics, 31(7), 373-381. doi:10.1016/j.tig.2015.04.008Fares, M. A., Keane, O. M., Toft, C., Carretero-Paulet, L., & Jones, G. W. (2013). The Roles of Whole-Genome and Small-Scale Duplications in the Functional Specialization of Saccharomyces cerevisiae Genes. PLoS Genetics, 9(1), e1003176. doi:10.1371/journal.pgen.1003176Freeling, M. (2006). Gene-balanced duplications, like tetraploidy, provide predictable drive to increase morphological complexity. Genome Research, 16(7), 805-814. doi:10.1101/gr.3681406GarcĂa-RodrĂguez, N., DĂaz de la Loza, M. del C., Andreson, B., Monje-Casas, F., Rothstein, R., & Wellinger, R. E. (2012). Impaired Manganese Metabolism Causes Mitotic Misregulation. Journal of Biological Chemistry, 287(22), 18717-18729. doi:10.1074/jbc.m112.358309Gemayel, R., Vinces, M. D., Legendre, M., & Verstrepen, K. J. (2010). Variable Tandem Repeats Accelerate Evolution of Coding and Regulatory Sequences. Annual Review of Genetics, 44(1), 445-477. doi:10.1146/annurev-genet-072610-155046Gout, J.-F., Duret, L., & Kahn, D. (2009). Differential Retention of Metabolic Genes Following Whole-Genome Duplication. Molecular Biology and Evolution, 26(5), 1067-1072. doi:10.1093/molbev/msp026Gout, J.-F., Kahn, D., & Duret, L. (2010). The Relationship among Gene Expression, the Evolution of Gene Dosage, and the Rate of Protein Evolution. PLoS Genetics, 6(5), e1000944. doi:10.1371/journal.pgen.1000944Gout, J.-F., & Lynch, M. (2015). Maintenance and Loss of Duplicated Genes by Dosage Subfunctionalization. Molecular Biology and Evolution, 32(8), 2141-2148. doi:10.1093/molbev/msv095Guan, Y., Dunham, M. J., & Troyanskaya, O. G. (2006). Functional Analysis of Gene Duplications inSaccharomyces cerevisiae. Genetics, 175(2), 933-943. doi:10.1534/genetics.106.064329Ibba, M. (1999). Quality Control Mechanisms During Translation. Science, 286(5446), 1893-1897. doi:10.1126/science.286.5446.1893Jansen, M. L. A., Diderich, J. A., Mashego, M., Hassane, A., de Winde, J. H., Daran-Lapujade, P., & Pronk, J. T. (2005). Prolonged selection in aerobic, glucose-limited chemostat cultures of Saccharomyces cerevisiae causes a partial loss of glycolytic capacity. Microbiology, 151(5), 1657-1669. doi:10.1099/mic.0.27577-0Kafri, R., Bar-Even, A., & Pilpel, Y. (2005). Transcription control reprogramming in genetic backup circuits. Nature Genetics, 37(3), 295-299. doi:10.1038/ng1523Keane, O. M., Toft, C., Carretero-Paulet, L., Jones, G. W., & Fares, M. A. (2014). Preservation of genetic and regulatory robustness in ancient gene duplicates ofSaccharomyces cerevisiae. Genome Research, 24(11), 1830-1841. doi:10.1101/gr.176792.114Kimura, M., & Takahata, N. (1983). Selective constraint in protein polymorphism: Study of the effectively neutral mutation model by using an improved pseudosampling method. Proceedings of the National Academy of Sciences, 80(4), 1048-1052. doi:10.1073/pnas.80.4.1048Lang, G. I., & Murray, A. W. (2011). Mutation Rates across Budding Yeast Chromosome VI Are Correlated with Replication Timing. Genome Biology and Evolution, 3, 799-811. doi:10.1093/gbe/evr054LaRiviere, F. J. (2001). Uniform Binding of Aminoacyl-tRNAs to Elongation Factor Tu by Thermodynamic Compensation. Science, 294(5540), 165-168. doi:10.1126/science.1064242Liti, G., Carter, D. M., Moses, A. M., Warringer, J., Parts, L., James, S. A., … Louis, E. J. (2009). Population genomics of domestic and wild yeasts. Nature, 458(7236), 337-341. doi:10.1038/nature07743Lohse, M., Bolger, A. M., Nagel, A., Fernie, A. R., Lunn, J. E., Stitt, M., & Usadel, B. (2012). RobiNA: a user-friendly, integrated software solution for RNA-Seq-based transcriptomics. Nucleic Acids Research, 40(W1), W622-W627. doi:10.1093/nar/gks540Makino, T., McLysaght, A., & Kawata, M. (2013). Genome-wide deserts for copy number variation in vertebrates. Nature Communications, 4(1). doi:10.1038/ncomms3283Marcet-Houben, M., & GabaldĂłn, T. (2015). Beyond the Whole-Genome Duplication: Phylogenetic Evidence for an Ancient Interspecies Hybridization in the Baker’s Yeast Lineage. PLOS Biology, 13(8), e1002220. doi:10.1371/journal.pbio.1002220Martin, P., Makepeace, K., Hill, S. A., Hood, D. W., & Moxon, E. R. (2005). Microsatellite instability regulates transcription factor binding and gene expression. Proceedings of the National Academy of Sciences, 102(10), 3800-3804. doi:10.1073/pnas.0406805102Mattenberger, F., Sabater-Muñoz, B., Hallsworth, J. E., & Fares, M. A. (2017). Glycerol stress inSaccharomyces cerevisiae: Cellular responses and evolved adaptations. Environmental Microbiology, 19(3), 990-1007. doi:10.1111/1462-2920.13603Mattenberger, F., Sabater-Muñoz, B., Toft, C., & Fares, M. A. (2016). The Phenotypic Plasticity of Duplicated Genes in Saccharomyces cerevisiae and the Origin of Adaptations. G3: Genes|Genomes|Genetics, 7(1), 63-75. doi:10.1534/g3.116.035329Nagalakshmi, U., Wang, Z., Waern, K., Shou, C., Raha, D., Gerstein, M., & Snyder, M. (2008). The Transcriptional Landscape of the Yeast Genome Defined by RNA Sequencing. Science, 320(5881), 1344-1349. doi:10.1126/science.1158441O’Hely, M. (2006). A Diffusion Approach to Approximating Preservation Probabilities for Gene Duplicates. Journal of Mathematical Biology, 53(2), 215-230. doi:10.1007/s00285-006-0001-6Ohno, S. (1999). Gene duplication and the uniqueness of vertebrate genomes circa 1970–1999. Seminars in Cell & Developmental Biology, 10(5), 517-522. doi:10.1006/scdb.1999.0332Papp, B., Pál, C., & Hurst, L. D. (2003). Dosage sensitivity and the evolution of gene families in yeast. Nature, 424(6945), 194-197. doi:10.1038/nature01771Park, C., Qian, W., & Zhang, J. (2012). Genomic evidence for elevated mutation rates in highly expressed genes. EMBO reports, 13(12), 1123-1129. doi:10.1038/embor.2012.165Payne, J. L., & Wagner, A. (2014). The Robustness and Evolvability of Transcription Factor Binding Sites. Science, 343(6173), 875-877. doi:10.1126/science.1249046Pu, S., Wong, J., Turner, B., Cho, E., & Wodak, S. J. (2008). Up-to-date catalogues of yeast protein complexes. Nucleic Acids Research, 37(3), 825-831. doi:10.1093/nar/gkn1005Qian, W., Liao, B.-Y., Chang, A. Y.-F., & Zhang, J. (2010). Maintenance of duplicate genes and their functional redundancy by reduced expression. Trends in Genetics, 26(10), 425-430. doi:10.1016/j.tig.2010.07.002Raghuraman, M. K. (2001). Replication Dynamics of the Yeast Genome. Science, 294(5540), 115-121. doi:10.1126/science.294.5540.115Rando, O. J., & Verstrepen, K. J. (2007). Timescales of Genetic and Epigenetic Inheritance. Cell, 128(4), 655-668. doi:10.1016/j.cell.2007.01.023Reynolds, N. M., Ling, J., Roy, H., Banerjee, R., Repasky, S. E., Hamel, P., & Ibba, M. (2010). Cell-specific differences in the requirements for translation quality control. Proceedings of the National Academy of Sciences, 107(9), 4063-4068. doi:10.1073/pnas.0909640107Robinson, M. D., McCarthy, D. J., & Smyth, G. K. (2009). edgeR: a Bioconductor package for differential expression analysis of digital gene expression data. Bioinformatics, 26(1), 139-140. doi:10.1093/bioinformatics/btp616Rockman, M. V., & Wray, G. A. (2002). Abundant Raw Material for Cis-Regulatory Evolution in Humans. Molecular Biology and Evolution, 19(11), 1991-2004. doi:10.1093/oxfordjournals.molbev.a004023Ruan, B., Palioura, S., Sabina, J., Marvin-Guy, L., Kochhar, S., LaRossa, R. A., & Soll, D. (2008). Quality control despite mistranslation caused by an ambiguous genetic code. Proceedings of the National Academy of Sciences, 105(43), 16502-16507. doi:10.1073/pnas.0809179105Schuster-Böckler, B., & Lehner, B. (2012). Chromatin organization is a major influence on regional mutation rates in human cancer cells. Nature, 488(7412), 504-507. doi:10.1038/nature11273Seoighe, C., & Wolfe, K. H. (1999). Yeast genome evolution in the post-genome era. Current Opinion in Microbiology, 2(5), 548-554. doi:10.1016/s1369-5274(99)00015-6Streelman, J. T., & Kocher, T. D. (2002). Microsatellite variation associated with prolactin expression and growth of salt-challenged tilapia. Physiological Genomics, 9(1), 1-4. doi:10.1152/physiolgenomics.00105.2001Supek, F., & Lehner, B. (2015). Differential DNA mismatch repair underlies mutation rate variation across the human genome. Nature, 521(7550), 81-84. doi:10.1038/nature14173Taylor, J. S., & Raes, J. (2004). Duplication and Divergence: The Evolution of New Genes and Old Ideas. Annual Review of Genetics, 38(1), 615-643. doi:10.1146/annurev.genet.38.072902.092831Tirosh, I., Barkai, N., & Verstrepen, K. J. (2009). Promoter architecture and the evolvability of gene expression. Journal of Biology, 8(11), 95. doi:10.1186/jbiol204Tong, A. H. Y. (2001). Systematic Genetic Analysis with Ordered Arrays of Yeast Deletion Mutants. Science, 294(5550), 2364-2368. doi:10.1126/science.1065810Vinces, M. D., Legendre, M., Caldara, M., Hagihara, M., & Verstrepen, K. J. (2009). Unstable Tandem Repeats in Promoters Confer Transcriptional Evolvability. Science, 324(5931), 1213-1216. doi:10.1126/science.1170097Wapinski, I., Pfeffer, A., Friedman, N., & Regev, A. (2007). Natural history and evolutionary principles of gene duplication in fungi. Nature, 449(7158), 54-61. doi:10.1038/nature06107Wolfe, K. H., & Shields, D. C. (1997). Molecular evidence for an ancient duplication of the entire yeast genome. Nature, 387(6634), 708-713. doi:10.1038/42711Yang, Z. (2007). PAML 4: Phylogenetic Analysis by Maximum Likelihood. Molecular Biology and Evolution, 24(8), 1586-1591. doi:10.1093/molbev/msm088Zaher, H. S., & Green, R. (2008). Quality control by the ribosome following peptide bond formation. Nature, 457(7226), 161-166. doi:10.1038/nature0758
Simulation of the Einstein-de Haas effect combining molecular and spin dynamics
The spin and lattice dynamics of a ferromagnetic nanoparticle are studied via
molecular dynamics and with semi-classical spin dynamics simulations where spin
and lattice degrees of freedom are coupled via a dynamic uniaxial anisotropy
term. We show that this model conserves total angular momentum, whereas spin
and lattice angular momentum are not conserved. We carry out simulations of the
the Einstein-de Haas effect for a Fe nanocluster with more than 500 atoms that
is free to rotate, using a modified version of the open-source spinlattice
dynamics code (SPILADY). We show that the rate of angular momentum transfer
between spin and lattice is proportional to the strength of the magnetic
anisotropy interaction. The addition of the anisotropy allows full spin-lattice
relaxation to be achieved on previously reported timescales of \sim 100 ps and
for tight-binding magnetic anisotropy energies comparable to those of small Fe
nanoclusters.Comment: 23 pages, 3 figure
The Role Of Omega-3 Polyunsaturated Fatty Acids In The Treatment Of Patients With Acute Respiratory Distress Syndrome: A Clinical Review
Acute respiratory distress syndrome (ARDS) is defined as the acute onset of noncardiogenic edema and subsequent gas-exchange impairment due to a severe inflammatory process. Recent report on the prognostic value of eicosanoids in patients with ARDS suggests that modulating the inflammatory response through the use of polyunsaturated fatty acids may be a useful strategy for ARDS treatment. The use of enteral diets enriched with eicosapentaenoic acid (EPA) and gamma-linolenic acid (GLA) has reported promising results, showing an improvement in respiratory variables and haemodynamics. However, the interpretation of the studies is limited by their heterogeneity and methodology and the effect of omega-3 fatty acid-enriched lipid emulsion or enteral diets on patients with ARDS remains unclear. Therefore, the routine use of omega-3 fatty acid-enriched nutrition cannot be recommended and further large, homogeneous, and high-quality clinical trials need to be conducted to clarify the effectiveness of omega-3 polyunsaturated fatty acids
Revalorization of Broccoli By-Products for Cosmetic Uses Using Supercritical Fluid Extraction
The agri-food industry is currently one of themain engines of economic developmentworldwide.
The region ofMurcia is a reference area in Europe for the cultivation of fruits and vegetables and produces
the bulk of Spanish exports of broccoli (Brassica oleracea var. italica). The processing of fresh produce
generates a huge number of by-products that represent an important economic and environmental problem
when discarded. In this work, an advanced extraction technique using environmentally friendly solvents
was applied to assess the revalorization of broccoli by-products, by performing a comparative analysis
with conventional extraction. To achieve this goal, supercritical fluid extraction based on response surface
methodology was performed using CO2 and ethanol as solvents. The results obtained showed that the
supercritical fluid extracts were rich in -carotene, phenolic compounds, chlorophylls and phytosterols.
Moreover, in bioactivity assays, the supercritical fluid extracts exhibited a high antioxidant activity and a
cytoprotective effect in a non-tumorigenic keratinocyte cell line exposed to ultraviolet B light. The results
indicate that supercritical fluid extracts from broccoli by-products could potentially serve as an ingredient
for cosmetic purposes
Dynamic bonding influenced by the proximity of adatoms to one atom high step edges
Low-temperature scanning tunneling microscopy is used here to study the dynamic bonding of gold atoms on surfaces under low coordination conditions. In the experiments, using an atomically sharp gold tip, a gold adatom is deposited onto a gold surface with atomic precision either on the first hollow site near a step edge or far away from it. Classical molecular dynamics simulations at 4.2 K and density-functional theory calculations serve to elucidate the difference in the bonding behavior between these two different placements, while also providing information on the crystalline classification of the STM tips based on their experimental performance.This work was supported by the Generalitat Valenciana through Grants No. CDEIGENT/2018/028, No. PROMETEO/2017/139, and No. PROMETEO/2021/017. The authors also acknowledge financial support from Spanish MICIN through Grant No. PID2019-109539 GB-C43, the MarĂa de Maeztu Program for Units of Excellence in R&D (Grant No. CEX2018-000805-M), the Comunidad AutĂłnoma de Madrid through the Nanomag COST-CM Program (Grant No. S2018/NMT-4321). The theoretical modeling was performed on the high-performance computing facilities of the University of South Africa and the University of Alicante. Netherlands Organization for Scientific Research (NWO/OCW) supported the experiments
Dynamic bonding influenced by the proximity of adatoms to one atom high step edges
Low-temperature scanning tunneling microscopy is used here to study the dynamic bonding of gold atoms on surfaces under low coordination conditions. In the experiments, using an atomically sharp gold tip, a gold adatom is deposited onto a gold surface with atomic precision either on the first hollow site near a step edge or far away from it. Classical molecular dynamics simulations at 4.2 K and density-functional theory calculations serve to elucidate the difference in the bonding behavior between these two different placements, while also providing information on the crystalline classification of the STM tips based on their experimental performanc
Formation of Common Investment Networks by Project Establishment between Agents
We present an investment model integrated with trust-reputation mechanisms
where agents interact with each other to establish investment projects. We
investigate the establishment of investment projects, the influence of the
interaction between agents in the evolution of the distribution of wealth, as
well as the formation of common investment networks and some of their
properties. Simulation results show that the wealth distribution presents a
power law in its tail. Also, it is shown that the trust and reputation
mechanism presented leads to the establishment of networks among agents, which
present some of the typical characteristics of real-life networks like a high
clustering coefficient and short average path length
- …