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81.
Moises Exposito‐Alonso Hajk‐Georg Drost Hernn A. Burbano Detlef Weigel 《The Plant journal : for cell and molecular biology》2020,102(2):222-229
Sequencing them all. That is the ambitious goal of the recently launched Earth BioGenome project (Proceedings of the National Academy of Sciences of the United States of America, 115, 4325–4333), which aims to produce reference genomes for all eukaryotic species within the next decade. In this perspective, we discuss the opportunities of this project with a plant focus, but highlight also potential limitations. This includes the question of how to best capture all plant diversity, as the green taxon is one of the most complex clades in the tree of life, with over 300 000 species. For this, we highlight four key points: (i) the unique biological insights that could be gained from studying plants, (ii) their apparent underrepresentation in sequencing efforts given the number of threatened species, (iii) the necessity of phylogenomic methods that are aware of differences in genome complexity and quality, and (iv) the accounting for within‐species genetic diversity and the historical aspect of conservation genetics. 相似文献
82.
Daniela Barro‐Trastoy Esther Carrera Jorge Baos Julia Palau‐Rodríguez Omar Ruiz‐Rivero Pablo Tornero Jos M. Alonso Isabel Lpez‐Díaz María Dolores Gmez Miguel A. Prez‐Amador 《The Plant journal : for cell and molecular biology》2020,102(5):1026-1041
Ovule primordia formation is a complex developmental process with a strong impact on the production of seeds. In Arabidopsis this process is controlled by a gene network, including components of the signalling pathways of auxin, brassinosteroids (BRs) and cytokinins. Recently, we have shown that gibberellins (GAs) also play an important role in ovule primordia initiation, inhibiting ovule formation in both Arabidopsis and tomato. Here we reveal that BRs also participate in the control of ovule initiation in tomato, by promoting an increase on ovule primordia formation. Moreover, molecular and genetic analyses of the co‐regulation by GAs and BRs of the control of ovule initiation indicate that two different mechanisms occur in tomato and Arabidopsis. In tomato, GAs act downstream of BRs. BRs regulate ovule number through the downregulation of GA biosynthesis, which provokes stabilization of DELLA proteins that will finally promote ovule primordia initiation. In contrast, in Arabidopsis both GAs and BRs regulate ovule number independently of the activity levels of the other hormone. Taken together, our data strongly suggest that different molecular mechanisms could operate in different plant species to regulate identical developmental processes even, as for ovule primordia initiation, if the same set of hormones trigger similar responses, adding a new level of complexity. 相似文献
83.
Alonso Alberto Pérez Javier Monroy Silvia López-Rojo Naiara Basaguren Ana Bosch Jaime Boyero Luz 《Ecosystems》2021,24(6):1436-1449
Ecosystems - Leaf litter of alder (Alnus glutinosa) is a key resource to detrital stream food webs. Due to its high quality and palatability, it is readily colonised by microorganisms and consumed... 相似文献
84.
CM van der Loos 《Biotechnic & histochemistry》2013,88(3):141-154
Three fixation issues related to immunostaining are discussed here: 1) Generally, a tissue block is fixed, then embedded and sectioned (pre-fixation). The type of fixative applied, crosslinking or coagulating, has an impact on selecting an epitope retrieval method. Individual antigens have a fixation–retrieval characteristic. 2) A long fixation time, especially with crosslinking fixatives, may compromise the result of immunostaining. This negative effect varies among different antigens and can be partially restored by applying a more sensitive/efficient detection system such as tyramide amplification. 3) Sections cut from a fresh frozen tissue block usually are acetone fixed (post-fixation). This was accepted as the “gold standard” for a long time. Post-fixation, however, may have serious consequences for preservation of small peptides leaking from the cut open cells, whereas this is not the case with pre-fixed intact cells. Consequently, the concept of an acetone post-fixed cryostat tissue section as “gold standard” no longer exists and a more appropriate use of the terms immunohistochemistry and immunocytochemistry therefore seems justified. For many antibodies, it is not known whether a formalin fixed, paraffin embedded tissue specimen is appropriate. Suggestions are made for creating a positive control cell block for testing such antibodies. 相似文献
85.
86.
Jorge Barrios-Muriel Francisco Romero Sánchez Francisco Javier Alonso Sánchez David Rodríguez Salgado 《Computer methods in biomechanics and biomedical engineering》2013,16(15):1219-1228
AbstractWhen designing any rehabilitation, sportswear or exoskeleton device the mechanical behaviour of the body segment must be known, specifically the skin, because an excessive tissue strain may lead to ulceration and bedsores. To date, it is not known if the kinematic variability between subjects have an effect on the skin strain field, and therefore, in the design and manufacturing of rehabilitation products, such as orthoses. Several studies have analysed the skin deformation during human motion, nevertheless, the comparison between the skin strain field in different subjects during normal or pathological gait has not been reported yet. This work presents a comparison of skin strain analysis for different gait patterns to study the differences between people and, specifically, if it is possible to standardize the orthotic design between subjects with the same gait disorder. Moreover, the areas with relatively minimum strain during the ankle-foot motion are compared to improve the design of structural parts of rehabilitation devices. In this case, a validated 3D digital image correlation system has been used for this purpose combined with strain ellipse theory. The results demonstrate variations in the skin strain field between subjects with the same pathology and similarities between subjects with normal gait. However, more studies and experiments are necessaries to validate this hypothesis and also to test it between different gait pathologies. 相似文献
87.
M. Pacheco M.A. Santos P. Pereira J.I. Martínez P.J. Alonso M.J. Soares J.C. Lopes 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2013,157(2):132-140
The impact of chromium (Cr) on fish health has been the subject of numerous investigations, establishing a wide spectrum of toxicity, attributed particularly to the hexavalent form [Cr(VI)]. However, reports on the simultaneous assessment of Cr toxicity in fish and its toxico-kinetics, namely involving metal speciation, are scarce. Therefore, keeping in view the understanding of the mechanisms of Cr(VI) toxicity, this work intended to detect the formation of paramagnetic Cr species in liver of Anguilla anguilla following short-term dichromate(VI) intraperitoneal treatment (up to 180 min), assessing simultaneously the pro-oxidant properties. The formation of Cr(V) and Cr(III) was examined by electron paramagnetic resonance (EPR), as an innovative approach in the context of fish toxicology, and related with the levels of total Cr. Cr(V) was successfully detected and quantified by EPR spectrometry, showing a transient occurrence, mostly between 15 and 90 min post-injection, with a peak at 30 min. The limitations of EPR methodology towards the detection and quantification of Cr(III) were confirmed. Although Cr(VI) exposure induced the antioxidant system in the eel's liver, the oxidative deterioration of lipids was not prevented. Overall, the results suggested that Cr(V), as a short-lived species, did not appear to be directly and primarily responsible for the cellular damaging effects observed, since stress responses persisted up to the end of exposure regardless Cr(V) drastic decay. Though further research is needed, ROS mediated pathways (suggested by superoxide dismutase and catalase activity induction) and formation of Cr(III) complexes emerged as the most plausible mechanisms involved in Cr(VI) toxicity. 相似文献
88.
Beatriz Aldaz Ainara Sagardoy Lorena Nogueira Elizabeth Guruceaga Lara Grande Jason T. Huse Maria A. Aznar Ricardo Díez-Valle Sonia Tejada-Solís Marta M. Alonso Jose L. Fernandez-Luna Jose A. Martinez-Climent Raquel Malumbres 《PloS one》2013,8(10)
Glioblastoma multiforme (GBM)-initiating cells (GICs) represent a tumor subpopulation with neural stem cell-like properties that is responsible for the development, progression and therapeutic resistance of human GBM. We have recently shown that blockade of NFκB pathway promotes terminal differentiation and senescence of GICs both in vitro and in vivo, indicating that induction of differentiation may be a potential therapeutic strategy for GBM. MicroRNAs have been implicated in the pathogenesis of GBM, but a high-throughput analysis of their role in GIC differentiation has not been reported. We have established human GIC cell lines that can be efficiently differentiated into cells expressing astrocytic and neuronal lineage markers. Using this in vitro system, a microarray-based high-throughput analysis to determine global expression changes of microRNAs during differentiation of GICs was performed. A number of changes in the levels of microRNAs were detected in differentiating GICs, including over-expression of hsa-miR-21, hsa-miR-29a, hsa-miR-29b, hsa-miR-221 and hsa-miR-222, and down-regulation of hsa-miR-93 and hsa-miR-106a. Functional studies showed that miR-21 over-expression in GICs induced comparable cell differentiation features and targeted SPRY1 mRNA, which encodes for a negative regulator of neural stem-cell differentiation. In addition, miR-221 and miR-222 inhibition in differentiated cells restored the expression of stem cell markers while reducing differentiation markers. Finally, miR-29a and miR-29b targeted MCL1 mRNA in GICs and increased apoptosis. Our study uncovers the microRNA dynamic expression changes occurring during differentiation of GICs, and identifies miR-21 and miR-221/222 as key regulators of this process. 相似文献
89.
Amanda P. Woon Abolghasem Tohidpour Hernan Alonso Yumiko Saijo-Hamano Terry Kwok Anna Roujeinikova 《PloS one》2013,8(11)
The CagA protein of Helicobacter pylori is associated with increased virulence and gastric cancer risk. CagA is translocated into the host cell by a H. pylori type IV secretion system via mechanisms that are poorly understood. Translocated CagA interacts with numerous host factors, altering a variety of host signalling pathways. The recently determined crystal structure of C-terminally-truncated CagA indicated the presence of two domains: the smaller, flexible N-terminal domain and the larger, middle domain. In this study, we have investigated the conformation, oligomeric state and stability of the N-terminal, middle and glutamate-proline-isoleucine-tyrosine-alanine (EPIYA)-repeats domains. All three domains are monomeric, suggesting that the multimerisation of CagA observed in infected cells is likely to be mediated not by CagA itself but by its interacting partners. The middle and the C-terminal domains, but not the N-terminal domain, are capable of refolding spontaneously upon heat denaturation, lending support to the hypothesis that unfolded CagA is threaded C-terminus first through the type IV secretion channel with its N-terminal domain, which likely requires interactions with other domains to refold, being threaded last. Our findings also revealed that the C-terminal EPIYA-repeats domain of CagA exists in an intrinsically disordered premolten globule state with regions in PPII conformation - a feature that is shared by many scaffold proteins that bind multiple protein components of signalling pathways. Taken together, these results provide a deeper understanding of the physicochemical properties of CagA that underpin its complex cellular and oncogenic functions. 相似文献
90.
Kate M. Scott Karestan C. Koenen Sergio Aguilar-Gaxiola Jordi Alonso Matthias C. Angermeyer Corina Benjet Ronny Bruffaerts Jose Miguel Caldas-de-Almeida Giovanni de Girolamo Silvia Florescu Noboru Iwata Daphna Levinson Carmen C. W. Lim Sam Murphy Johan Ormel Jose Posada-Villa Ronald C. Kessler 《PloS one》2013,8(11)