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Prefoldins Negatively Regulate Cold Acclimation in Arabidopsis thaliana by Promoting Nuclear Proteasome-Mediated HY5 Degradation

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Molecular Plant 2017年第6期10卷 791-804页

作者： Carlos Perea-Resa Miguel A. Rodriguez-Milla Elisa Iniesto Vicente Rubio Julio Salinas Departamento de Biologia Medioambiental Centro de Investigaciones Biologicas CSIC 28040 Madrid Spain Departamento de Genetica Molecular de Plantas Centro Nacional de Biotecnologia CSIC 28049 Madrid Spain present address: Department of Molecular Biology Massachusetts General Hospital Boston MA 02214 USA Present address: Unidad de Biotecnologia Celular Instituto de Salud Garlos Ⅲ 28222 Madrid Spain

The process of cold acclimation is an important adaptive response whereby many plants from temperate regions increase their freezing tolerance after being exposed to low non-freezing temperatures. The correct development of this response relies on proper accumulation of a number of transcription factors that regulate expression patterns of cold-responsive genes. Multiple studies have revealed a variety of molecular mechanisms involved in promoting the accumulation of these transcription factors. Interestingly, however, the mechanisms implicated in controlling such accumulation to ensure their adequate levels remain largely unknown. In this work, we demonstrate that prefoldins （PFDs） control the levels of HY5, an Arabidopsis transcription factor with a key role in cold acclimation by activating anthocyanin biosynthesis, in response to low temperature. Our results show that, under cold conditions, PFDs accumulate into the nucleus through a DELLA-dependent mechanism, where they interact with HY5, triggering its ubiquitination and subsequent degradation. The degradation of HY5 would result, in turn, in anthocyanin biosynthesis attenuation, ensuring the accurate development of cold acclimation. These findings uncover an unanticipated nuclear function for PFDs in plant responses to abiotic stresses.

关键词： prefoldins cold acclimation Arabidopsis HY5 anthocyanin DELLAs

Valorization of Kraft Lignin as Thickener in Castor Oil for Lubricant Applications

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Journal of Renewable Materials 2018年第4期6卷 347-361页

作者： A.M.Borrero-Lopez F.J.Santiago-Medina C.Valencia M.E.Eugenio R.Martin-Sampedro J.M.Franco Department of Chemical Engineering University of HuelvaEl Carmen CampusAgrifood Campus of International Excellence(ceiA3)21071 HuelvaSpain Pro2TecS-Chemical Process and Product Technology Research Center University of Huelva21071 HuelvaSpain INIA-CIFOR Ctra de la Coruñakm 7.5.28040MadridSpain

It is known that large amounts of residual lignin are generated in the pulp and paper industry.A new alternative for Kraft lignin valorization,which consists of first a chemical modification using a diisocyanate and then the efficient dispersion in castor oil to achieve stable gel-like systems,is proposed in this *** properties and microstructure of these materials were determined by means of small amplitude oscillatory shear tests and viscous flow measurements and atomic force microscopy observations,***,both standardized penetration tests and tribological assays,usually performed in the lubricant industry,were carried out to evaluate the performance characteristics as lubricating *** viscoelasticity functions are affected by the lignin/diisocyanate ratio and thickener *** thermorheological response evidenced a softening temperature of around 105°*** microstructure of these gel-like dispersions is composed of interconnected thin fibers,homogeneously distributed in castor ***,the NCO-functionalized lignin gel-like dispersions studied show lower friction coefficients than traditional lubricating greases.

关键词： Kraft lignin diisocyanate gel-like dispersion rheology thermal properties

Towards full repair of defects in reduced graphene oxide films by two-step graphitization

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Nano Research 2013年第3期6卷 216-233页

作者： Ruben Rozada Juan I, Paredes Silvia Villar-Rodil Amelia Marlinez-Alonso Juan M. D. Tascon Instituto Nacional del Carbon INCAR-CSIC Apartado 73 33080 Oviedo Spain

The complete restoration of a perfect carbon lattice has been a central issue in the research on graphene derived from graphite oxide since this preparation route was first proposed several years ago, but such a goal has so far remained elusive. Here, we demonstrate that the highly defective structure of reduced graphene oxide sheets assembled into free-standing, paper-like films can be fully repaired by means of high temperature annealing （graphitization）. Characterization of the films by X-ray photoelectron and Raman spectroscopy, X-ray diffraction and scanning tunneling microscopy indicated that the main stages in the transformation of the films were （i） complete removal of oxygen functional groups and generation of atomic vacancies （up to 1,500 ~C）, and （ii） vacancy annihilation and coalescence of adjacent overlapping sheets to yield continuous polycrystalline layers （1,800-2,700 ~C） similar to those of highly oriented graphites. The prevailing type of defect in the polycrystalline layers were the grain boundaries separating neighboring domains, which were typically a few hundred nanometers in lateral size, exhibited long-range graphitic order and were virtually free of even atomic-sized defects. The electrical conductivity of the annealed films was as high as 577,000 S-m-1, which is by far the largest value reported to date for any material derived from graphene oxide, and strategies for further improvement without the need to resort to higher annealing temperatures are suggested. Overall, this work opens the prospect of truly achieving a complete restoration of the carbon lattice in graphene oxide materials.

关键词： graphene graphene oxide films annealing defect

Dual role of FGF in proliferation and endoreplication of Drosophila tracheal adult progenitor cells

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Journal of Molecular Cell Biology 2020年第1期12卷 32-41页

作者： Cristina de Miguel Josefa Cruz David Martin Xavier Franch-Marro Institute of Evolutionary Biology(Consejo Superior de Investigaciones Cientificas-Universitat Pompeu Fabra) Passeig Maritim de la Barceloneta 3708003 BarcelonaSpain

Adult progenitor cells activation is a key event in the formation of adult *** Drosophilat formation of abdominal adult trachea depends on the specific activation of tracheal adult progenitors(tracheoblasts)at the Tr4 and Tr5 spiracular *** of these tracheoblasts generates a pool of tracheal cells that migrate toward the posterior part of the trachea by the activation of the branchless/fibroblast growth factor(Bnl/FGF)signaling to form the abdominal adult ***,we show that,in addition to migration,Bnl/FGF signaling,mediated by the transcription factor Pointed,is also required for tracheoblast *** tracheoblast activation relies on the expression of the FGF ligand bnl in their nearby ***,we show that,in the absence of the transcription factor Cut(Ct),Bnl/FGF signaling induces endoreplication of tracheoblasts partially by promoting fizzy-related ***,our results suggest a dual role of Bnl/FGF signaling in tracheoblasts,inducing both proliferation and endoreplication,depending on the presence or absence of the transcription factor Ct,respectively.

关键词： FGF trachea adult progenitors cut proliferation endoreplication Pnt Fzr

Strain-induced band gap engineering in layered TiS3

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Nano Research 2018年第1期11卷 225-232页

作者： Robert Biele Eduardo Flores Jose Ramon Ares Carlos Sanchez Isabel J. Ferrer Gabino Rubio-Bollinger Andres Castellanos-Gomezs Roberto D'Agosta Nano-Bio Spectroscopy Group and European Theoretical Spectroscopy Facility (EFSF) Universidad del Pals Vasco 20018 San Sebastidn Spain Materials of Interest in Renewable Energies Group (MIRE Group) Dpto. de Fisica de Materiales Universidad Aut6noma de Madrid 28049 Madrid Spain Instituto de Ciencia de Materiales "Nicolds Cabrera" Campus de Cantoblanco 28049 Madrid Spain Dpto. de Ffsica de la Materia Condensada Condensed Matter Physics Center (IFIMAC) Universidad Aut6noma de Madrid Campus de Cantoblanco 28049 Madrid Spain Instituto de Ciencia de los Materiales de Madrid (ICMM-CSIC) Cantoblanco 28049 Madrid Spain IKERBASQUE Basque Foundation for Science 48013 Bilbao Spain

By combining ab initio calculations and experiments, we demonstrate how the band gap of the transition metal trichalcogenide TiS3 can be modified by inducing tensile or compressive strain. In addition, using our calculations, we predicted that the material would exhibit a transition from a direct to an indirect band gap upon application of a compressive strain in the direction of easy electrical transport. The ability to control the band gap and its nature could have a significant impact on the use of TiS3 for optical applications. We go on to verify our prediction via optical absorption experiments that demonstrate a band gap increase of up to 9% （from 0.99 to 1.08 eV） upon application of tensile stress along the easy transport direction.

关键词： band gap engineering titanium trisulfide 2-D materials strain

Design of active and stable catalysts by embedding nitrogen-doped carbon oxygen reduction reaction CoxOy nanoparticles into

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Nano Research 2017年第1期10卷 97-107页

作者： Fan Yang Mikel Abadia Chaoqiu Chen Weike Wang Le Li Lianbing Zhang Celia Rogero Andrey Chuvilin Mato Knez CIC nanoGUNE Consofider Tolosa Hifibidea 76 20018 Donostia-San Sebastian Spain Centro de Fisica de Materials CFM/MPC (CSIC-UPV/EHU) Paseo Manuel de Lardizabal 5 20018 Donostia-San Sebastian Spain School of Life Sciences Northwestern Polytechnical University Xi'an 710072 China Donostia International Physics Center (DIPC) Paseo Manuel de Lardizabal 4 20018 Donostia-San Sebastian Spain IKERBASQUE Basque Foundation for Science Maria Diaz de Haro 3 48013 Bilbao Spain

The oxygen reduction reaction （ORR） is essential in research pertaining to life science and energy. In applications, platinum-based catalysts give ideal reactivity, but, in practice, are often subject to high costs and poor stability. Some costefficient transition metal oxides have exhibited excellent ORR reactivity, but the stability and durability of such alternative catalyst materials pose serious challenges. Here, we present a facile method to fabricate uniform CoxOy nanoparticles and embed them into N-doped carbon, which results in a composite of extraordinary stability and durability, while maintaining its high reactivity. The half-wave potential shows a negative shift of only 21 mV after 10,000 cycles, only one third of that observed for Pt/C （63 mV）. Furthermore, after 100,000 s testing at a constant potential, the current decreases by only 17%, significantly less than for Pt/C （35%）. The exceptional stability and durability results from the system architecture, which comprises a thin carbon shell that prevents agglomeration of the CoxOy nanoparticles and their detaching from the substrate.

关键词： atomic layer deposition cobalt oxide polydopamine oxygen reduction reaction

Comparison of different statistical approaches to evaluate morphometric sperm subpopulations in men

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Asian Journal of Andrology 2016年第6期18卷 819-823页

作者： Jesus L Yaniz Sandra Vicente-Fiel Caries Soler Pilar Recreo Teresa Carretero Araceli Bono Jose M Berne Pilar Santolaria TECNOGAM research group Environmental Sciences Institute (IUCA) Department of Animal Production and Food Sciences Higher Polytechnic School University of Zaragoza Ctra. Cuarte S/N 22071 Huesca Spain Department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Valencia Spain R+D Department Proiser R+D Scientific Park University of Valencia 46980 Paterna Valencia Spain TECNOGAM research group Environmental Sciences Institute (IUCA) Departament of Human Anatomy and Histology Faculty of Health and Sport Sciences of Huesca Plaza Universidad 3 22002 Huesca Spain TECNOGAM research group Environmental Sciences Institute (IUCA) Hospital General San Jorge de Huesca Area de Urologla Av. Martfnez de Velasco 36 22004 Huesca Spain

This study was designed to characterize morphometric sperm subpopulations in normozoospermic men by using different statistical methods and examining their suitability to classify correctly different sperm nuclear morphologies present in human ejaculates. Ejaculates from 21 normozoospermic men were collected for the study. After semen collection and analysis, samples were prepared for morphometric determination. At least 200 spermatozoa per sample were assessed for sperm morphometry by computer-assisted sperm morphometry analysis （CASA-Morph） using fluorescence. Clustering and discriminant procedures were performed to identify sperm subpopulations from the morphometric data obtained. Clustering procedures resulted in the classification of spermatozoa into three morphometric subpopulations （large-round 30.4%, small-round 46.6%, and large-elongated 22.9%）. In the second analysis, using discriminant methods, the classification was made independently of size and shape. Three morphological categories according to nuclear size （small 〈10.90 μm^2, intermediate 10.91-13.07 μm^2, and large 〉13.07 μm^2） and four categories were defined on 400 canonical cells （100 × 4） from 10 men according to sperm nuclear shape （oval, pyriform, round, and elongated）. Thereafter, the resulting classification functions were used to categorize 4200 spermatozoa from 21 men. Differences in the class distribution were observed among men from both clustering and discriminant procedures. It was concluded that the combination of CASA-Morph fluorescence-based technology with multivariate cluster or discriminant analyses provides new information on the description of different morphometric sperm subpopulations in normal individuals, and that important variations in the distribution of morphometric sperm subpopulations may exist between men, with possible functional implications.

关键词： computer-assisted sperm morphometry analysis man sperm subpopulations

Morphometric and kinematic sperm subpopulations in split ejaculates of normozoospermic men

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Asian Journal of Andrology 2016年第6期18卷 831-834页

作者： Pilar Santolaria Caries Soler Pilar Recreo Teresa Carretero Araceli Bono Jose M Berne Jesus L Yaniz TECNOGAM research group Environmental Sciences Institute (IUCA) Department of Animal Production and Food Sciences University of Zaragoza Huesca Spain Department of Functionat 8iotogy and Physical Anthropology University of Valencia 46100 Burjassot Valencia Spain R+D Department Proiser R+D Scientific Park University of Valencia 46980 Paterna Valencia Spain TECNOGAM research group Environmental Sciences Institute (IUCA) Departament of Human Anatomy and Histolosy Faculty of Health and Sport Sciences of Huesca PLaza Universidad 3 22002 Huesca Spain TECNOGAM research group Environmental Sciences Institute (IUCA) Hospital General San Jorge de Huesca Area de Urologia Av. Martinez de Velasco 36 22004 Huesca Spain

This study was designed to analyze the sperm kinematic and morphometric subpopulations in the different fractions of the ejaculate in normozoospermic men. Ejaculates from eight normozoospermic men were collected by masturbation in three fractions after 3-5 days of sexual abstinence. Analyses of sperm motility by computer-assisted sperm analysis （CASA-Mot）, and of sperm morphometry by computer-assisted sperm morphometry analysis （CASA-Morph） using fluorescence were performed. Clustering and discriminant procedures were performed to identify sperm subpopulations in the kinematic and morphometric data obtained. Clustering procedures resulted in the classification of spermatozoa into three kinematic subpopulations （slow with low ALH [35.6% of all motile spermatozoa], with circular trajectories [32.0%], and rapid with high ALH [32.4%]）, and three morphometric subpopulations （large-round [33.9% of all spermatozoa], elongated [32.0%], and small [34.10%]）. The distribution of kinematic sperm subpopulations was different among ejaculate fractions （P 〈 0.001）, with higher percentages of spermatozoa exhibiting slow movements with low ALH in the second and third portions, and with a more homogeneous distribution of kinematic sperm subpopulations in the first portion. The distribution of morphometric sperm subpopulations was also different among ejaculate fractions （P〈 0.001）, with more elongated spermatozoa in the first, and of small spermatozoa in the third, portion. It is concluded that important variations in the distribution of kinematic and morphometric sperm subpopulations exist between ejaculate fractions, with possible functional implications.

关键词： man sperm morphometry by computer-assisted sperm morphometry analysis sperm motility by computer-assisted spermanalysis sperm subpopulations split ejaculate

FPn-Injective, FPn-Flat Covers and Preenvelopes, and Gorenstein AC-Flat Covers

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Algebra Colloquium 2018年第2期25卷 319-334页

作者： Daniel Bravo Sergio Estrada Alina Iacob Instituto de Ciencias Fisicas y Matematicas Facultad de Ciencias Universidad Austral de Chile Valdivia Chile Departamento de Matematicas Universidad de Murcia Campus de Espinardo 30100 Murcia Spain Department of Mathematical Sciences Georgia Southern University Statesboro GA 30460 U.S.A

We prove that, for any n 〉 2, the classes of FPn-injective modules and of FPn-flat modules are both covering and preenveloping over any ring R. This includes the case of FP∞-injective and FP∞-flat modules （i.e., absolutely clean and, respectively, level modules）. Then we consider a generalization of the class of （strongly） Gorenstein flat modules, i.e., the （strongly） Gorenstein AC-flat modules （cycles of exact complexes of flat modules that remain exact when tensored with any absolutely clean module）. We prove that some of the properties of Gorenstein fiat modules extend to the class of Gorenstein AC-flat modules; for example, we show that this class is precovering over any ring R. We also show that （as in the case of Gorenstein flat modules） every Gorenstein AC-flat module is a direct summand of a strongly Gorenstein AC-flat module. When R is such that the class of Gorenstein AC-flat modules is closed under extensions, the converse is also true. Moreover, we prove that if the class of Gorenstein AC-flat modules is closed under extensions, then it is covering.

关键词： FPn-injective module FPn-flat module Ding injective module GorensteinAC-flat module