Differential gene expression signatures for cell wall integrity found in chitin synthase II (chs2Δ) and myosin II (myo1Δ) deficient cytokinesis mutants of Saccharomyces cerevisiae

<p>Abstract</p> <p>Background</p> <p>Myosin II-dependent contraction of the cytokinetic ring and primary septum formation by chitin synthase II are interdependent processes during cytokinesis in <it>Saccharomyces cerevisiae</it>. Hence, null mutants of myosin II <it>(myo1</it>Δ<it>) </it>and chitin synthase II <it>(chs2</it>Δ<it>) </it>share multiple morphological and molecular phenotypes. To understand the nature of their interdependent functions, we will seek to identify genes undergoing transcriptional regulation in <it>chs2</it>Δ strains and to establish a transcription signature profile for comparison with <it>myo1</it>Δ strains.</p> <p>Results</p> <p>A total of 467 genes were commonly regulated between <it>myo1Δ </it>and <it>chs2Δ </it>mutant strains (p ≤ 0.01). Common regulated biological process categories identified by Gene Set Enrichment Analysis (GSEA) in both gene expression profiles were: protein biosynthesis, RNA processing, and stress response. Expression of 17/20 genes in the main transcriptional fingerprint for cell wall stress was confirmed in the <it>chs2Δ </it>strain versus 5/20 for the <it>myo1Δ </it>strain. One of these genes, <it>SLT2/MPK1</it>, was up-regulated in both strains and both strains accumulated the hyperphosphorylated form of Slt2p thereby confirming that the <it>PKC1 </it>cell wall integrity pathway (CWIP) was activated by both mutations. The <it>SLT2/MPK1 </it>gene, essential for <it>myo1Δ </it>strains, was not required in the <it>chs2Δ </it>strain.</p> <p>Conclusion</p> <p>Comparison of the <it>chs2Δ </it>and <it>myo1</it>Δ gene expression profiles revealed similarities in the biological process categories that respond to the <it>chs2Δ </it>and <it>myo1</it>Δ gene mutations. This supports the view that these mutations affect a common function in cytokinesis. Despite their similarities, these mutants exhibited significant differences in expression of the main transcriptional fingerprint for cell wall stress and their requirement of the CWIP for survival.</p

Homocysteine treatment alters redox capacity of both endothelial and tumor cells

Homocysteine is a non-proteinogenic amino acid playing key roles in two interconnected metabolic pathways, namely, the activated methyl cycle and the linear trans-sulfuration pathway that allows the conversion of methionine to cysteine. A dysregulation of intracellular homocysteine metabolism could yield an increased export of this amino acid, leading to hyperhomocysteinemia, which has been associated with an increased risk of cardiovascular diseases. In spite of decades of experimental effort, there is no definitive consensus on what could be the molecular mechanisms whereby hyperhomocysteinemia could contribute to cardiovascular disease. The redox active nature of homocysteine has favored the idea of an induction of oxidative stress as the underlying mechanism of homocysteine toxicity. In contrast, homocysteine can also behave as an anti-oxidant. The present work is aimed to further analyze the capacity of homocysteine to modulate the redox capacity of both endothelial and tumor cells. [Our experimental work is supported by grants BIO2014-56092-R (MINECO and FEDER) and P12-CTS-1507 (Andalusian Government and FEDER) and funds from group BIO-267 (Andalusian Government). The "CIBER de Enfermedades Raras" is an initiative from the ISCIII (Spain)].Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Global mRNA expression analysis in myosin II deficient strains of Saccharomyces cerevisiae reveals an impairment of cell integrity functions

<p>Abstract</p> <p>Background</p> <p>The <it>Saccharomyces cerevisiae MYO1 </it>gene encodes the myosin II heavy chain (Myo1p), a protein required for normal cytokinesis in budding yeast. Myo1p deficiency in yeast (<it>myo1Δ</it>) causes a cell separation defect characterized by the formation of attached cells, yet it also causes abnormal budding patterns, formation of enlarged and elongated cells, increased osmotic sensitivity, delocalized chitin deposition, increased chitin synthesis, and hypersensitivity to the chitin synthase III inhibitor Nikkomycin Z. To determine how differential expression of genes is related to these diverse cell wall phenotypes, we analyzed the global mRNA expression profile of <it>myo1Δ </it>strains.</p> <p>Results</p> <p>Global mRNA expression profiles of <it>myo1Δ </it>strains and their corresponding wild type controls were obtained by hybridization to yeast oligonucleotide microarrays. Results for selected genes were confirmed by real time RT-PCR. A total of 547 differentially expressed genes (p ≤ 0.01) were identified with 263 up regulated and 284 down regulated genes in the <it>myo1Δ </it>strains. Gene set enrichment analysis revealed the significant over-representation of genes in the protein biosynthesis and stress response categories. The <it>SLT2/MPK1 </it>gene was up regulated in the microarray, and a <it>myo1Δslt2Δ </it>double mutant was non-viable. Overexpression of ribosomal protein genes <it>RPL30 </it>and <it>RPS31 </it>suppressed the hypersensitivity to Nikkomycin Z and increased the levels of phosphorylated Slt2p in <it>myo1Δ </it>strains. Increased levels of phosphorylated Slt2p were also observed in wild type strains under these conditions.</p> <p>Conclusion</p> <p>Following this analysis of global mRNA expression in yeast <it>myo1Δ </it>strains, we conclude that 547 genes were differentially regulated in <it>myo1Δ </it>strains and that the stress response and protein biosynthesis gene categories were coordinately regulated in this mutant. The <it>SLT2/MPK1 </it>gene was confirmed to be essential for <it>myo1Δ </it>strain viability, supporting that the up regulated stress response genes are regulated by the <it>PKC1 </it>cell integrity pathway. Suppression of Nikkomycin Z hypersensitivity together with Slt2p phosphorylation was caused by the overexpression of ribosomal protein genes <it>RPL30 </it>and <it>RPS31</it>. These ribosomal protein mRNAs were down regulated in the <it>myo1Δ </it>arrays, suggesting that down regulation of ribosomal biogenesis may affect cell integrity in <it>myo1Δ </it>strains.</p

The Holocene volcanism of Gran Canaria (Canary Islands, Spain)

This work presents the first detailed map of the Holocene eruptions of Gran Canaria (Canary Islands, Spain). It provides complete and detailed information for all 24 Holocene eruptions of Gran Canaria, improving the knowledge of this recent volcanism and the assessment of volcanic hazards on the island. This map is a synthesis of collated and interpreted field data and topographic maps. We have integrated information obtained from: (1) detailed geological field surveys, (2) morphometric analysis of eruptive deposits, (3) high-resolution digital elevation models, and (4) aerial photographs

The psychometric properties of the person-centered therapeutic relationship in physiotherapy scale

[EN] Objective To determine the psychometric properties of the Person-Centered Therapeutic Relationship in Physiotherapy Scale (PCTR-PT) in order to find the most appropriate fit for the tool. Methods Patients who had received treatment at the physiotherapy service of nine hospitals in Spain were invited to complete the 31 items of the PCTR-PT scale. To select the most appropriate items of the PCTR-PT, an exploratory factorial analysis (EFA) was performed using the maximum likelihood and oblique rotation (promin) methods. Factor validity, goodness-of-fit and psychometric properties were analyzed by confirmatory factor analysis (CFA). Convergent (CFA) and discriminant validity were calculated. Internal consistency was verified using the Cronbach's alpha coefficient. The intraclass correlation coefficient (ICC) was used to examine temporal stability. Results 366 patients over 18 years old who had received, at least, 15 physiotherapy treatment sessions completed the questionnaire. The results of the exploratory factor analysis revealed a tool with 15 items in four factors [Relational Bond (N items = 4); Individualized Partnership (N items = 4); Professional Empowerment (N items = 3) and Therapeutic Communication (N items = 4)], explaining 78.4% of the variance of the total variables of this tool. The confirmatory factor analysis further confirmed the four-structure model. Reliability of the tool was approved by Cronbach's alpha in all four dimensions, as all were above .70, ranging from .84 (Individualized Partnership) to .91 (Professional Empowerment). = 0.94. Test-retest was performed with two-week intervals, indicating an appropriate stability for the scale (ICC = 0.900). Conclusion The Person-Centered Therapeutic Relationship in Physiotherapy Scale (PCTR-PT) is a useful, valid and applicable instrument to evaluate the person-centered therapeutic relationship during physiotherapy interventions. It would be interesting to investigate the predictive capacity (sensitivity and specificity) of the PCTR-PT scale.SIAuthors JMB, ORN, are recipients of a grant from CEU Cardenal Herrera University (www. uchceu.es) and the San Pablo University-Santander Foundation (FUSP). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Absence of molecular evidence of Leptospira spp. in urine samples collected from rodents captured in Yucatán, México

Leptospira spp. is a spirochete bacteria, causal agent of leptospirosis, zoonotic disease endemic in México that represents a serious public health and veterinary problem. Rodents are recognised as the most important reservoirs of this bacteria, which is transmitted mainly through direct or indirect contact with the Leptospira spp. excreted in the urine of infected individuals. Theaim of this study was to evaluate the circulation of Leptospira spp. in urine samples of wild and synanthropic rodents from Yucatán, México. Eighty-four rodents were captured in the community of Cenotillo, Yucatán. Twenty-six urine samples were collected from the bladder and were used in the total DNA extraction. The identification of Leptospira spp. was intended through the polymerase chain reaction test in its endpoint variant. No evidence of Leptospira spp. was found in the urine samples. It is necessary to use other tissues for the identification of Leptospira spp., before concluding that the rodents used in the present study are not reservoirs of this bacteri

Toward the Discovery of Biological Functions Associated with the Mechanosensor Mtl1p of \u3ci\u3eSaccharomyces cerevisiae\u3c/i\u3e via Integrative Multi-OMICs Analysis

Functional analysis of the Mtl1 protein in Saccharomyces cerevisiae has revealed that this transmembrane sensor endows yeast cells with resistance to oxidative stress through a signaling mechanism called the cell wall integrity pathway (CWI). We observed upregulation of multiple heat shock proteins (HSPs), proteins associated with the formation of stress granules, and the phosphatase subunit of trehalose 6-phosphate synthase which suggests that mtl1Δ strains undergo intrinsic activation of a non-lethal heat stress response. Furthermore, quantitative global proteomic analysis conducted on TMT-labeled proteins combined with metabolome analysis revealed that mtl1Δ strains exhibit decreased levels of metabolites of carboxylic acid metabolism, decreased expression of anabolic enzymes and increased expression of catabolic enzymes involved in the metabolism of amino acids, with enhanced expression of mitochondrial respirasome proteins. These observations support the idea that Mtl1 protein controls the suppression of a non-lethal heat stress response under normal conditions while it plays an important role in metabolic regulatory mechanisms linked to TORC1 signaling that are required to maintain cellular homeostasis and optimal mitochondrial function

Identification and Functional Testing of Novel Interacting Protein Partners for the Stress Sensors Wsc1p and Mid2p of \u3cem\u3eSaccharomyces cerevisiae\u3c/em\u3e

Wsc1p and Mid2p are transmembrane signaling proteins of cell wall stress in the budding yeast Saccharomyces cerevisiae. When an environmental stress compromises cell wall integrity, they activate a cell response through the Cell Wall Integrity (CWI) pathway. Studies have shown that the cytoplasmic domain of Wsc1p initiates the CWI signaling cascade by interacting with Rom2p, a Rho1-GDP-GTP exchange factor. Binding of Rom2p to the cytoplasmic tail of Wsc1p requires dephosphorylation of specific serine residues but the mechanism by which the sensor is dephosphorylated and how it subsequently interacts with Rom2p remains unclear. We hypothesize that Wsc1p and Mid2p must be physically associated with interacting proteins other than Rom2p that facilitate its interaction and regulate the activation of CWI pathway. To address this, a cDNA plasmid library of yeast proteins was expressed in bait strains bearing membrane yeast two-hybrid (MYTH) reporter modules of Wsc1p and Mid2p, and their interacting preys were recovered and sequenced. 14 previously unreported interactors were confirmed for Wsc1p and 29 for Mid2p. The interactors’ functionality were assessed by cell growth assays and CWI pathway activation by western blot analysis of Slt2p/Mpk1p phosphorylation in null mutants of each interactor under defined stress conditions. The susceptibility of these strains to different stresses were tested against antifungal agents and chemicals. This study reports important novel protein interactions of Wsc1p and Mid2p that are associated with the cellular response to oxidative stress induced by Hydrogen Peroxide and cell wall stress induced by Caspofungin

REPORT ON THE 2020 ICCAT WORKSHOP ON SMALL TUNAS BIOLOGY STUDIES FOR GROWTH AND REPRODUCTION.

SUMMARY This report describes the 2020 ICCAT workshop on small tunas biology studies for growth and reproduction, hosted by the Instituto Español de Oceanografía, Málaga, Spain. The major objectives of the workshop were: 1) starting the creation of ageing and reproduction reference sets and, 2) providing more training for the ongoing sample collection and processing to the teams involved in these studies. As approved by the SCRS in 2017, the Small Tuna Species Group intersessional meeting decided to prioritize the collection of biological samples aiming at growth, maturity and stock structure studies on three species: little tunny (Euthynnus alletteratus), Atlantic Bonito (Sarda sarda) and wahoo (Acanthocybium solandri), based on their economic importance and the lack of knowledge on their biology. This work will contribute to the next major advance in the assessment of these three species. RÉSUMÉ Le présent rapport décrit l'atelier de l’ICCAT tenu en 2020 sur les études de la biologie des thonidés mineurs pour la croissance et la reproduction, organisé par l'Instituto Español de Oceanografía, à Malaga, en Espagne. Les principaux objectifs de l'atelier étaient les suivants : 1) commencer à créer des ensembles de référence sur la détermination de l’âge et la reproduction et 2) fournir une formation plus poussée sur la collecte et le traitement des échantillons aux équipes participant à ces études. Tel qu’approuvé par le SCRS en 2017, lors de la réunion intersessions du Groupe d'espèces sur les thonidés mineurs, il a été décidé de donner la priorité à la collecte d'échantillons biologiques visant à étudier la croissance, la maturité et la structure des stocks de trois espèces : la thonine commune (Euthynnus alletteratus), la bonite à dos rayé (Sarda) et le thazard-bâtard (Acanthocybium solandri), sur la base de leur importance économique et des connaissances lacunaires sur leur biologie. Ces travaux contribueront à la prochaine grande avancée dans l'évaluation de ces trois espèces. RESUMEN Este informe describe el taller de ICCAT de 2020 sobre estudios de biología de pequeños túnidos para crecimiento y reproducción, acogido por el Instituto Español de Oceanografía en Málaga, España. Los principales objetivos del taller eran: 1) empezar la creación de conjuntos de referencia de determinación de la edad y reproducción y 2) facilitar más formación a los equipos involucrados en estos estudios para la recopilación de muestras y procesamiento en curso. Como aprobó el SCRS en 2017, en la Reunión intersesiones del Grupo de especies de pequeños túnidos se decidió priorizar la recopilación de muestras biológicas con miras a estudios de crecimiento, madurez y estructura del stock de tres especies: bacoreta (Euthynnus alletteratus), bonito (Sarda sarda) y peto (Acanthocybium solandri), basándose en su importancia económica y la falta de conocimientos sobre su biología. Este trabajo contribuirá a avanzar en la próxima evaluación de estas tres especies.Versión del edito