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Mitochondrial activity adapts to cellular energetic and metabolic demands; its dysfunction is a hallmark of ageing and many human diseases. The evolutionarily conserved translation elongation factor eIF5A is involved in maintaining mitochondrial function. In humans, eIF5A is encoded by two highly homologous but differentially expressed genes; in yeast, these are TIF51A and TIF51B. We show that yeast transcription factor Hap1 constitutively binds to the TIF51A promoter to activate its expression under respiration, but represses its expression under nonrespiration conditions by recruiting the corepressor Tup1. Hap1 indirectly regulates TIF51B expression by binding to and activating the TIF51B repressor genes ROX1 and MOT3 under respiration and repressing them under nonrespiration. Thus, the levels of eIF5A isoforms are adapted to the mitochondrial functional status.

Iron participates as an essential cofactor in the biosynthesis of critical cellular components, including DNA, proteins and lipids. The ergosterol biosynthetic pathway, which is an important target of antifungal treatments, depends on iron in four enzymatic steps. Our results in the model yeast Saccharomyces cerevisiae show that the expression of ergosterol biosynthesis (ERG) genes is tightly modulated by iron availability probably through the iron-dependent variation of sterol and heme levels. Whereas the transcription factors Upc2 and Ecm22 are responsible for the activation of ERG genes upon iron deficiency, the heme-dependent factor Hap1 triggers their Tup1-mediated transcriptional repression. The combined regulation by both activating and repressing regulatory factors allows for the fine-tuning of ERG transcript levels along the progress of iron deficiency, avoiding the accumulation of toxic sterol intermediates and enabling efficient adaptation to rapidly changing conditions. The lack of these regulatory factors leads to changes in the yeast sterol profile upon iron-deficient conditions. Both environmental iron availability and specific regulatory factors should be considered in ergosterol antifungal treatments., This research was supported by grant PID2020-116940RB-I00 funded by MCIN/AEI/10.13039/501100011033 to Sergi Puig, grants PID2020-120066RB-I00 funded by MCIN/AEI/10.13039/501100011033 and AICO/2020/086 by ‘Generalitat Valenciana’ to Paula Alepuz, and grant RED2018-102467-T funded by MCIN/AEI/10.13039/501100011033 to Sergi Puig and Paula Alepuz. Tania Jordá was a recipient of a predoctoral fellowship ACIF/2019/214 funded by ‘Generalitat Valenciana’, and Marina Barba-Aliaga was a recipient of a predoctoral fellowship (FPU2017/03542) funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your future. The authors also acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

The eukaryotic translation initiation factor 5A (eIF5A) is an evolutionarily conserved protein that binds ribosomes to facilitate the translation of peptide motifs with consecutive prolines or combinations of prolines with glycine and charged amino acids. It has also been linked to other molecular functions and cellular processes, such as nuclear mRNA export and mRNA decay, proliferation, differentiation, autophagy, and apoptosis. The growing interest in eIF5A relates to its association with the pathogenesis of several diseases, including cancer, viral infection, and diabetes. It has also been proposed as an anti-aging factor: its levels decay in aged cells, whereas increasing levels of active eIF5A result in the rejuvenation of the immune and vascular systems and improved brain cognition. Recent data have linked the role of eIF5A in some pathologies with its function in maintaining healthy mitochondria. The eukaryotic translation initiation factor 5A is upregulated under respiratory metabolism and its deficiency reduces oxygen consumption, ATP production, and the levels of several mitochondrial metabolic enzymes, as well as altering mitochondria dynamics. However, although all the accumulated data strongly link eIF5A to mitochondrial function, the precise molecular role and mechanisms involved are still unknown. In this review, we discuss the findings linking eIF5A and mitochondria, speculate about its role in regulating mitochondrial homeostasis, and highlight its potential as a target in diseases related to energy metabolism.

Translation elongation factor eIF5A binds to ribosomes to promote peptide bonds between problematic amino acids for the reaction like prolines. eIF5A is highly conserved and essential in eukaryotes, which usually contain two similar but differentially expressed paralogue genes. The human eIF5A-1 isoform is abundant and implicated in some cancer types, the eIF5A-2 isoform is absent in most cells but becomes overexpressed in many metastatic cancers. Several reports have connected eIF5A and mitochondria because it co-purifies with the organelle or its inhibition reduces respiration and mitochondrial enzyme levels. However, the mechanisms of eIF5A mitochondrial function, and whether eIF5A expression is regulated by the mitochondrial metabolism, are unknown. We analysed the expression of yeast eIF5A isoforms Tif51A and Tif51B under several metabolic conditions and in mutants. The depletion of Tif51A, but not Tif51B, compromised yeast growth under respiration and reduced oxygen consumption. Tif51A expression followed dual positive regulation: by high glucose through TORC1 signalling, like other translation factors, to promote growth and by low glucose or non-fermentative carbon sources through Snf1 and heme-dependent transcription factor Hap1 to promote respiration. Upon iron depletion, Tif51A was down-regulated and Tif51B up-regulated. Both were Hap1-dependent. Our results demonstrate eIF5A expression regulation by cellular metabolic status.

The present study aimed to analyze if a preformed “hybrid” patient-specific orbital mesh provides a more accurate reconstruction of the orbital floor and a better functional outcome than a standardized, intraoperatively adapted titanium implant. Thirty patients who had undergone surgical reconstruction for isolated, unilateral orbital floor fractures between May 2016 and November 2018 were included in this study. Of these patients, 13 were treated conventionally by intraoperative adjustment of a standardized titanium mesh based on assessing the fracture’s shape and extent. For the other 17 patients, an individual three-dimensional (3D) anatomical model of the orbit was fabricated with an in-house 3D-printer. This model was used as a template to create a so-called “hybrid” patient-specific titanium implant by preforming the titanium mesh before surgery. The functional and cosmetic outcome in terms of diplopia, enophthalmos, ocular motility, and sensory disturbance trended better when “hybrid” patient-specific titanium meshes were used but with statistically non-significant differences. The 3D-printed anatomical models mirroring the unaffected orbit did not delay the surgery’s timepoint. Nonetheless, it significantly reduced the surgery duration compared to the traditional method (58.9 (SD: 20.1) min versus 94.8 (SD: 33.0) min, p-value = 0.003). This study shows that using 3D-printed anatomical models as a supporting tool allows precise and less time-consuming orbital reconstructions with clinical benefits.

Translation of mRNAs that encode peptide sequences with consecutive prolines (polyproline) requires the conserved and essential elongation factor eIF5A to facilitate the formation of peptide bonds. It has been shown that, upon eIF5A depletion, yeast ribosomes stall in polyproline motifs, but also in tripeptide sequences that combine proline with glycine and charged amino acids. Mammalian collagens are enriched in putative eIF5A-dependent Pro-Gly-containing tripeptides. Here, we show that depletion of active eIF5A in mouse fibroblasts reduced collagen type I α1 chain (Col1a1) content, which concentrated around the nuclei. Moreover, it provoked the upregulation of endoplasmic reticulum (ER) stress markers, suggesting retention of partially synthesized collagen 1 (Col1) in the ER. We confirmed that eIF5A is needed for heterologous collagen synthesis in yeast and, using a double luciferase reporter system, showed that eIF5A depletion interrupts translation at Pro-Gly collagenic motifs. A dramatically lower level of Col1a1 protein was also observed in functional eIF5A-depleted human hepatic stellate cells treated with the profibrotic cytokine TGF-β1. In sum, our results show that collagen expression requires eIF5A and imply its potential as a target for regulating collagen production in fibrotic diseases.

The evolutionary conserved elongation factor eIF5A is required for the translation of mRNAs that encode protein sequences with consecutive prolines or combined with glycine and charged amino acids. Mammalian collagens are enriched in putative eIF5A-dependent Pro-Gly-containing tripeptides. Here, we show that eIF5A is needed for heterologous expression of collagen in yeast, and using a dual luciferase reporter system we confirmed that eIF5A depletion interrupts translation at Pro-Gly-collagenic motifs. Using mouse fibroblasts, we showed that depletion of active eIF5A reduced collagen 1α (Col1a1) content, which became concentrated around the nuclei, in contrast to a stronger and all over the cell collagen signal in untreated cells. Active eIF5A-depleted mouse fibroblast showed upregulation of endoplasmic reticulum (ER) stress markers, suggesting retention of partially synthesized Col1a1 in the ER. A dramatically lower level of Col1α1 protein was also observed in functional eIF5A-depleted human hepatic stellate cells treated with the profibrotic cytokine TGF-β1. Our results show that collagen expression requires eIF5A and imply its potential as a target for regulating collagen production in fibrotic diseases.

The chapter deals with the history of the discovery of viruses in the late 19 century as well as the progress made over the last 120 years in advancing the science of plant virology. These include but are not limited to biology of virus-or viroid-infected plants, vector and non-vector transmission, the rise of molecular and biophysical virology, replication of RNA and DNA viruses as well as viroids, and many methods used in plant virology. These methods include serology, electron microscopy, confocal microscopy, analytical and preparative ultracentrifugation, density gradient ultracentrifugation, gel electrophoresis, hybridization. polymerase chain reaction, microarrays, genetic engineering, first and next-generation nucleotide sequencing, CRISPR-Cas system editing and several others. Finally, control of viruses and viroids by exclusion was also discussed.

espanolDentro de su bidimensionalidad, la fotografia dispone un orden de planos de profundidad en la representacion del espacio construido. La distancia que se abre entre la posicion del espectador y los primeros objetos representados inicia esta secuencia de llenos y vacios. El primer vacio es consecuencia de una decision activa y sera territorio de tension permanente, limite permeable e interseccion clave de significados. Como hace evidente el analisis que se realiza a partir de una imagen de Thomas Ruff, plantear la funcionalidad de este espacio vacio delante de la arquitectura fotografiada equivale a preguntarse por la cuestion de la objetividad, vertice del debate sobre los fundamentos teoricos de la fotografia y su posicion en el arte contemporaneo en las ultimas decadas. EnglishWithin its bidimensionality, photograpphy has an order of depth shots in the representation of the constructed space. The distance that stretches between the position of the spectator and the first objects represented begins this sequence of negative and positive space. The first negative space is a consequence of an active decision and will be the area of permanent tension: a permeable limit and key intersection between meanings. As the analysis performed using an image by Thomas Ruff indicates, deliberating the practicility of this negative space in front of the photographed architecture is equivalent to considering the question of objectivity, which is, in turn, the apex of the debate regardingthe theoretical foundations of photography and its position in contemporary art in recent decades.

Iñaki Bergera (ed.)Lucien Hervé, España blanca y España negra / White Spain and Black SpainMadrid: Turner, coeditado con el Ministerio de Fomento, Colección Arte y Foto, 2019. 244 págs. Edición en rústica, dos tomos. Idiomas: español e inglés. 24 €.ISBN-13: 978-8417866013

Heterobasidion annosum s.s. and H. parviporum are severe pathogens of conifers causing butt rot and root rot thus reducing the economic value of timber. Here, the antifungal activity of Bacillus subtilis isolate A18 against these two Heterobasidion species was investigated. Five different culture media with different culture age were investigated to study the effect of substrate composition and culture age for metabolite production. Bacterial cultures and cell-free culture filtrates were tested for antifungal activity. Inhibition of fungal growth was analysed using the agar disc-diffusion method. MALDI-TOF and LC-HRMS analyses were used to identify the antifungal metabolites. Substrate composition and age of culture were found to be active variables with direct effect on the antifungal activity of bacterial culture extracts. High anti-fungal activity was observed when B. subtilis was cultured in PDB, SGB and LB media for four days. Mass-spectrometry analysis showed the presence of lipopeptides in culture filtrates identified as members of the surfactins, polymixins, kurstakins and fengycins. A culture filtrate containing fengycin-type lipopeptides showed the highest bioactivity against Heterobasidion species. Bacterial cultures had higher bioactivity compared to their respective cell free culture filtrates. The results of the present study suggest that B. subtilis A18 is a powerful biocontrol agent against Heterobasidion infections of tree wounds and stumps.

Glioblastoma multiforme (GBM) is the most frequent and aggressive type of brain tumor due, at least in part, to its poor response to current anticancer treatments. These features could be explained, at least partially, by the presence within the tumor mass of a small population of cells termed Glioma Initiating Cells (GICs) that has been proposed to be responsible for the relapses occurring in this disease. Thus, the development of novel therapeutic approaches (and specifically those targeting the population of GICs) is urgently needed to improve the survival of the patients suffering this devastating disease. Previous observations by our group and others have shown that Δ9-Tetrahydrocannabinol (THC, the main active ingredient of marijuana) and other cannabinoids including cannabidiol (CBD) exert antitumoral actions in several animal models of cancer, including gliomas. We also found that the administration of THC (or of THC + CBD at a 1:1 ratio) in combination with temozolomide (TMZ), the benchmark agent for the treatment of GBM, synergistically reduces the growth of glioma xenografts. In this work we investigated the effect of the combination of TMZ and THC:CBD mixtures containing different ratios of the two cannabinoids in preclinical glioma models, including those derived from GICs. Our findings show that TMZ + THC:CBD combinations containing a higher proportion of CDB (but not TMZ + CBD alone) produce a similar antitumoral effect as the administration of TMZ together with THC and CBD at a 1:1 ratio in xenografts generated with glioma cell lines. In addition, we also found that the administration of TMZ + THC:CBD at a 1:1 ratio reduced the growth of orthotopic xenografts generated with GICs derived from GBM patients and enhanced the survival of the animals bearing these intracranial xenografts. Remarkably, the antitumoral effect observed in GICs-derived xenografts was stronger when TMZ was administered together with cannabinoid combinations containing a higher proportion of CBD. These findings support the notion that the administration of TMZ together with THC:CBD combinations - and specifically those containing a higher proportion of CBD - may be therapeutically explored to target the population of GICs in GBM. This work has been funded by the PI15/00339 grant, integrated into the State Plan for R & D + I2013-2016 and funded by the Instituto de Salud Carlos III (ISCIII) (Spain) and the European Regional Development Fund (ERDF) and by grants from Spanish Ministry of Economy and Competitiveness (MINECO)/ISCIII and ERDF (PS09/01401; PI12/02248,to GV), GW Pharma Ltd. (UK), Comunidad de Madrid (Spain) (S2011/BMD-2308 to MG), Fundación Mutua Madrileña (Spain) (AP101042012 to GV), Fundació La Marató de TV3 (Spain) (201334031 to GV), Voices Against Brain Cancer (US), and donations by The Medical Cannabis Bike Tour Foundation (The Netherlands) and Jeff Ditchfield. Israel López-Valero was supported by a predoctoral P-FIS contract from Instituto de Salud Carlos III (ISCIII) and Cristina Sáiz was supported by a “Juan de la Cierva formación” contract of the Spanish Ministry of Economy and Competitiveness. Sí

“Te toca a ti” es un taller activo y colaborativo en torno a la realidad social de la imagen y la experiencia de la arquitectura. Propone como objetivos una visión crítica de la comunicación mediática de las intervenciones en nuestras ciudades, la articulación de un discurso colectivo del uso de los nuevos espacios de trabajo y ocio, y la construcción de expresiones alternativas desde el lenguaje fotográfico como medio de emancipación. Un discurso visual no es una imagen aislada. Del mismo modo, la interpretación del espectador no se limita a una acción individual. En la propuesta de trabajo se plantea deconstruir, técnica y culturalmente, la imagen colectiva que tenemos de la arquitectura sobre una serie de edificios seleccionados. A partir de la experiencia sensible, atendiendo los principios de la arquitectura emocional, y de la voz de colectivos de usuarios y visitantes, se podrá formar una base reactiva de participación profunda para elaborar desde ella una crítica alternativa. El taller se desarrolla en cuatro fases, correspondientes a otros "It's your turn" is an active and collaborative workshop that deals with the social reality of images and how architecture is experienced. The goal is to enable its participants to adopt a critical stance regarding how interventions in our cities are communicated through the media, by articulating a collective discourse about the use of the new work and leisure spaces, and constructing alternative expressions with the use of photographic language as a means of emancipation. A visual discourse is not an isolated image. In this same sense, the viewer's interpretation is not limited to an individual action. Our work methodology proposes deconstructing, both technically and culturally, the collective image we have of architecture through a selection of buildings. On the basis of this sensory experience, and taking into consideration the principles of emotional architecture as well as the views of users and visitors, we will be able to give shape to a reactive, committed, participatory base upon which to elaborate an alternative critique.

Within the family Avsunviroidae, encompassing viroids that replicate in plastids through a rolling-circle mechanism involving hammerhead ribozymes, peach latent mosaic viroid (PLMVd) is the type member of genus Pelamoviroid. With a size varying ranging from 335 to 351 nt, due to the presence of an insertion in some sequence variants, PLMVd adopts a branched conformation stabilized by a kissing-loop interaction in the plus strand. Most PLMVd infections in peach are symptomless, although certain PLMVd isolates induce leaf mosaics/blotches and albinism (peach calico, PC), fruit deformations and discolorations, delays in foliation, flowering, and ripening, and reduced longevity. Small (21 nt) viroid-derived RNAs containing the 12–14 nt insertion that characterizes PC-inducing isolates most likely cause PC by guiding cleavage of a host mRNA as predicted by RNA silencing. PLMVd, which has been detected in the major peach-growing areas worldwide, is transmitted by infected propagation material, pruning tools, aphids, and pollen, but not by seeds.

Viroids cannot be controlled by therapeutic treatments in fields, orchards, vineyards, or palm plantations. Hence, the elimination of viroids from infected plants has been a challenging issue and different approaches have been studied to produce viroid-free planting material. This chapter describes viroid elimination by thermotherapy, cold therapy, tissue culture, in vitro micrografting, or cryotherapy to obtain viroid-free materials. Elevated temperatures do not inactivate or eliminate most viroids from their host plants, whereas cold therapy can be effective depending on the host–viroid system. Meristem culture and shoot-tip micrografting are good methods to obtain viroid-free plants: the eradication rate depends on the size of the shoot, the viroid or its variant, and the host and its variety. The combination of thermotherapy plus shoot-tip culture is more effective for viroid elimination. Cryotherapy of shoot tips, an innovative technique for pathogen eradication based on cryopreservation, did not result in viroid elimination. Further experiments on other host–viroid systems and on combination of cold therapy and cryotherapy are under evaluation.

The movement of host plant germplasm risks the introduction of viroids to new sites. The International Plant Protection Convention is a treaty that aims to harmonize phytosanitary measures to promote safe trade, and provide guidance in improving the quality of propagation and planting material. Quarantine is considered a primary strategy to prevent the introduction of pests in areas that are otherwise free of the target plant pathogens. Postentry quarantine involves some form of isolation of the imported germplasm, usually accompanied by observations for any symptom as well as diagnostic testing for the pests of concern. On the other hand phytosanitary certification is a system whereby countries have an obligation to ensure that exported plants are free of pests of concern to the importing country. Phytosanitary certification and quarantine programs contribute to reducing the risk of the inadvertent movement of several viroids, considered very damaging and a threat to agriculture.

Apple scar skin viroid (ASSVd) causes serious pome fruit diseases such as apple scar skin, dapple apple, pear rusty skin, pear fruit crinkle, and pear dimple fruit. Diseased apple and pear fruits are unmarketable. The viroid may also be latent in some pear cultivars without causing a disease. ASSVd was reported from many countries, especially those of East Asia. It naturally infects different species of apple and pear as well as apricot, peach, sweet cherry, and Himalayan wild cherry. Nucleotide sequences of several ASSVd variants from different hosts were determined and comparative sequence analyses were made. Using genetic engineering approaches, ASSVd is transmitted to herbaceous plant species. The viroid is also transmitted by the greenhouse whitefly to herbaceous hosts. Other means of transmission, detection, and control are similar to those of other temperate fruit tree viroids.

The beginning of the era of next-generation sequencing (NGS) started early in the 21st century. Since then the NGS industry has expanded with several companies marketing different sequencing platforms that are becoming faster, more efficient, and cheaper to operate. NGS technologies combined with advances in bioinformatics have been successfully utilized in viroid research and diagnosis since 2009, particularly in the areas of genome and small RNA sequencing, discovery, detection, and viroid–host interactions. The use of these technologies in viroid diagnostics can potentially improve the efficiency and reliability of plant health certification and quarantine programs by controlling viroid diseases at both national and international levels.

Microarrays are an emerging methodology in viroid detection and identification. The principle is the hybridization of fluorescently labeled sequences (targets) to complementary probe sequences immobilized on a solid surface. The process includes probe development, array fabrication, target preparation, hybridization, washing, scanning, and interpretation of results. Probe design and labeling of the target are the key steps in detection and identification of viroids by microarrays. The main advantage of this methodology is the opportunity to detect many viroids simultaneously. Microarrays may be viroid-specific, or may be used for broad-spectrum screening with the use of genus-level probes, the latter being suitable for detecting newly emerging viroids, or established viroids occurring in new host or geographical regions.

Since 1997, research on the host range of peach latent mosaic viroid has been gradually extended outside peach and peach hybrids, to include: other stone fruits such as almond, apricot, cherry, Japanese apricot (mume), Japanese plum, European plum (prune); the pome fruits, apple, pear, quince, and wild pear; and a few nonrosaceous species. Geographically, it has been found in 20 countries in Europe, Africa, Asia, and North and South America. No clear data are available on the symptomatology and economic significance of peach latent mosaic viroid in these species.