109 research outputs found

    A Multicriteria Model to Evaluate Strategic Plans for the Nautical and Naval Industry in Cartagena de Indias, Colombia

    Full text link
    [EN] The evaluation of urban development plans is a key concern of the strategic planning of the city of Cartagena de Indias (Colombia) due to the pressure exerted by both public and private sectors. Any strategic planning requirement deserves the inclusion of clear terms of coordination and cooperation among sectors, including local communities and the scientific sector. In this paper, we present a methodology for the sustainable evaluation of strategic nautical and naval projects for the development of the city of Cartagena de Indias. The methodology is based on the multicriteria technique Analytic Network Process, which allows considering political, socio-cultural and environmental aspects. The aim is to provide answers and guide the decision makers towards the optimal selection of strategies. Results provide some important insights into the overall conception of what sustainable evaluation means for the experts consulted. The procedure enhances participation and transparency and becomes a support for their decisions.The authors would like to thank the "Bolivar Gana con Ciencia" project from the Gobernacion de Bolivar (Colombia) for the financial support. Special thanks are also extended to the experts for their enthusiastic cooperation, which made this study possible.Gonzalez-Urango, H.; García-Melón, M. (2017). A Multicriteria Model to Evaluate Strategic Plans for the Nautical and Naval Industry in Cartagena de Indias, Colombia. Sustainability. 9(4). https://doi.org/10.3390/su9040653S9

    Identification of a novel type of spacer element required for imprinting in fission yeast

    Get PDF
    Asymmetrical segregation of differentiated sister chromatids is thought to be important for cellular differentiation in higher eukaryotes. Similarly, in fission yeast, cellular differentiation involves the asymmetrical segregation of a chromosomal imprint. This imprint has been shown to consist of two ribonucleotides that are incorporated into the DNA during laggingstrand synthesis in response to a replication pause, but the underlying mechanism remains unknown. Here we present key novel discoveries important for unravelling this process. Our data show that cis-acting sequences within the mat1 cassette mediate pausing of replication forks at the proximity of the imprinting site, and the results suggest that this pause dictates specific priming at the position of imprinting in a sequence-independent manner. Also, we identify a novel type of cis-acting spacer region important for the imprinting process that affects where subsequent primers are put down after the replication fork is released from the pause. Thus, our data suggest that the imprint is formed by ligation of a not-fullyprocessed Okazaki fragment to the subsequent fragment. The presented work addresses how differentiated sister chromatids are established during DNA replication through the involvement of replication barriers

    FH3, A Domain Found in Formins, Targets the Fission Yeast Formin Fus1 to the Projection Tip During Conjugation

    Get PDF
    Formins are involved in diverse aspects of morphogenesis, and share two regions of homology: FH1 and FH2. We describe a new formin homology region, FH3. FH3 is an amino-terminal domain that differs from the Rho binding site identified in Bni1p and p140mDia. The Schizosaccharomyces pombe formin Fus1 is required for conjugation, and is localized to the projection tip in cells of mating pairs. We replaced genomic fus1+ with green fluorescent protein (GFP)- tagged versions that lacked either the FH1, FH2, or FH3 domain. Deletion of any FH domain essentially abolished mating. FH3, but neither FH1 nor FH2, was required for Fus1 localization. An FH3 domain–GFP fusion protein localized to the projection tips of mating pairs. Thus, the FH3 domain alone can direct protein localization. The FH3 domains of both Fus1 and the S. pombe cytokinesis formin Cdc12 were able to localize GFP to the spindle pole body in half of the late G2 cells in a vegetatively growing population. Expression of both FH3-GFP fusions also affected cytokinesis. Overexpression of the spindle pole body component Sad1 altered the distribution of both Sad1 and the FH3-GFP domain. Together these data suggest that proteins at multiple sites can interact with FH3 domains

    Improved tools for efficient mapping of fission yeast genes: identification of microtubule nucleation modifier mod22-1 as an allele of chromatin- remodelling factor gene swr1

    Get PDF
    Fission yeast genes identified in genetic screens are usually cloned by transformation of mutants with plasmid libraries. However, for some genes this can be difficult, and positional cloning approaches are required. The mutation swi5-39 reduces recombination frequency in homozygous crosses and has been used as a tool in mapping gene position (Schmidt, 1993). However, strain construction in swi5-39-based mapping is significantly more laborious than is desirable. Here we describe a set of strains designed to make swi5-based mapping more efficient and more powerful. The first improvement is the use of a swi5Δ strain marked with kanamycin (G418) resistance, which greatly facilitates identification of swi5 mutants. The second improvement, which follows directly from the first, is the introduction of a large number of auxotrophic markers into mapping strains, increasing the likelihood of finding close linkage between a marker and the mutation of interest. We combine these new mapping strains with a rec12Δ-based approach for initial mapping of a mutation to an individual chromosome. Together, the two methods allow an approximate determination of map position in only a small number of crosses. We used these to determine that mod22-1, a modifier of microtubule nucleation phenotypes, encodes a truncation allele of Swr1, a chromatin-remodelling factor involved in nucleosomal deposition of H2A.Z histone variant Pht1. Expression microarray analysis of mod22-1, swr1Δ and pht1Δ cells suggests that the modifier phenotype of mod22-1 mutants may be due to small changes in expression of one or more genes involved in tubulin function. Copyright © 2009 John Wiley & Sons, Ltd

    The role of the RACK1 ortholog Cpc2p in modulating pheromone-induced cell cycle arrest in fission yeast

    Get PDF
    The detection and amplification of extracellular signals requires the involvement of multiple protein components. In mammalian cells the receptor of activated C kinase (RACK1) is an important scaffolding protein for signal transduction networks. Further, it also performs a critical function in regulating the cell cycle by modulating the G1/S transition. Many eukaryotic cells express RACK1 orthologs, with one example being Cpc2p in the fission yeast Schizosaccharomyces pombe. In contrast to RACK1, Cpc2p has been described to positively regulate, at the ribosomal level, cells entry into M phase. In addition, Cpc2p controls the stress response pathways through an interaction with Msa2p, and sexual development by modulating Ran1p/Pat1p. Here we describe investigations into the role, which Cpc2p performs in controlling the G protein-mediated mating response pathway. Despite structural similarity to Gβ-like subunits, Cpc2p appears not to function at the G protein level. However, upon pheromone stimulation, cells overexpressing Cpc2p display substantial cell morphology defects, disorientation of septum formation and a significantly protracted G1 arrest. Cpc2p has the potential to function at multiple positions within the pheromone response pathway. We provide a mechanistic interpretation of this novel data by linking Cpc2p function, during the mating response, with its previous described interactions with Ran1p/Pat1p. We suggest that overexpressing Cpc2p prolongs the stimulated state of pheromone-induced cells by increasing ste11 gene expression. These data indicate that Cpc2p regulates the pheromone-induced cell cycle arrest in fission yeast by delaying cells entry into S phase

    Fission yeast Ags1 confers the essential septum strength needed for safe gradual cell abscission

    Get PDF
    [EN]Fungal cytokinesis requires the assembly of a dividing septum wall. In yeast, the septum has to be selectively digested during the critical cell separation process. Fission yeast cell wall alpha (1-3) glucan is essential, but nothing is known about its localization and function inthe cell wall or about cooperation between the alpha - and beta (1-3) glucan synthases Ags1 and Bgs for cell wall and septum assembly. Here, we generate a physiological Ags1-GFP variant and demonstrate a tight colocalization with Bgs1, suggesting a cooperation in the important early steps of septum construction. Moreover, we define the essential functions of alpha(1-3) glucan in septation and cell separation. We show that alpha (1-3) glucan is essential for both secondary septum formation and the primary septum structural strength needed to support the physical forces of the cell turgor pressure during cell separation. Consequently, the absence of Ags1 and therefore alpha(1-3)glucan generates a special and unique side-explosive cell separation due to an instantaneous primary septum tearing caused by the turgor pressure

    The Fission Yeast Stress-Responsive MAPK Pathway Promotes Meiosis via the Phosphorylation of Pol II CTD in Response to Environmental and Feedback Cues

    Get PDF
    The RRM-type RNA-binding protein Mei2 is a master regulator of meiosis in fission yeast, in which it stabilizes meiosis-specific mRNAs by blocking their destruction. Artificial activation of Mei2 can provoke the entire meiotic process, and it is suspected that Mei2 may do more than the stabilization of meiosis-specific mRNAs. In our current study using a new screening system, we show that Mei2 genetically interacts with subunits of CTDK-I, which phosphorylates serine-2 residues on the C-terminal domain of RNA polymerase II (Pol II CTD). Phosphorylation of CTD Ser-2 is essential to enable the robust transcription of ste11, which encodes an HMG-type transcription factor that regulates the expression of mei2 and other genes necessary for sexual development. CTD Ser-2 phosphorylation increases under nitrogen starvation, and the stress-responsive MAP kinase pathway, mediated by Wis1 MAPKK and Sty1 MAPK, is critical for this stress response. Sty1 phosphorylates Lsk1, the catalytic subunit of CTDK-I. Furthermore, a feedback loop stemming from activated Mei2 to Win1 and Wis4 MAPKKKs operates in this pathway and eventually enhances CTD Ser-2 phosphorylation and ste11 transcription. Hence, in addition to starting meiosis, Mei2 functions to reinforce the commitment to it, once cells have entered this process. This study also demonstrates clearly that the stress-responsive MAP kinase pathway can modulates gene expression through phosphorylation of Pol II CTD

    TORC2-Gad8 dependent myosin phosphorylation modulates regulation by calcium

    Get PDF
    Cells respond to changes in their environment through signalling networks that modulate cytoskeleton and membrane organisation to coordinate cell cycle progression, polarised cell growth and multicellular development. Here, we define a novel regulatory mechanism by which the motor activity and function of the fission yeast type 1 myosin, Myo1, is modulated by TORC2 signalling dependent phosphorylation. Phosphorylation of the conserved serine at position 742 within the neck region changes both the conformation of the neck region and the interactions between Myo1 and its associating calmodulin light chains. S742 phosphorylation thereby couples calcium and TOR signalling networks in the modulation of myosin-1 dynamics to co-ordinate actin polymerisation and membrane reorganisation at sites of endocytosis and polarised cell growth in response to environmental and cell cycle cues

    Análisis del comportamiento de la línea de costa y clasificación morfológica de la zona costera de Manzanillo del Mar en la ciudad de Cartagena De Indias

    No full text
    Tesis (Ingeniero Civil)-- Universidad de Cartagena. Facultad de Ciencias e Ingenierías. Programa de Ingeniería Civil, 2017El presente estudio tiene por objeto establecer la variabilidad estacional de la línea de costa en la zona de Manzanillo del Mar de la ciudad de Cartagena mediante el levantamiento de perfiles de playa y toma de muestras de sedimento, para determinar posibles riesgos de inundación o peligro para los bañistas
    corecore