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1.
Int J Mol Sci ; 24(21)2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37958690

RESUMEN

Thermotropic mesogens typically exist as liquid crystals (LCs) in a narrow region of high temperatures, making lowering their melting point with the temperature expansion of the mesophase state an urgent task. Para-substituted benzoic acids can form LCs through noncovalent dimerization into homodimers via hydrogen bonds, whose strength and, consequently, the temperature region of the mesophase state can be potentially altered by creating asymmetric heterodimers from different acids. This work investigates equimolar blends of p-n-alkylbenzoic (kBA, where k is the number of carbon atoms in the alkyl radical) and p-n-alkyloxybenzoic (kOBA) acids by calorimetry and viscometry to establish their phase transitions and regions of mesophase existence. Non-symmetric dimerization of acids leads to the extension of the nematic state region towards low temperatures and the appearance of new monotropic and enantiotropic phase transitions in several cases. Moreover, the crystal-nematic and nematic-isotropic phase changes have a two-step character for some acid blends, suggesting the formation of symmetric and asymmetric associates from heterodimers. The mixing of 6BA and 8OBA most strongly extends the region of the nematic state towards low temperatures (from 95-114 °C and 108-147 °C for initial homodimers, respectively, to 57-133 °C for the resulting heterodimer), whereas the combination of 4OBA and 5OBA gives the most extended high-temperature nematic phase (up to 156 °C) and that of 6BA and 9OBA (or 12OBA) provides the existence of a smectic phase at the lowest temperatures (down to 51 °C).


Asunto(s)
Cristales Líquidos , Cristales Líquidos/química , Calorimetría , Temperatura , Transición de Fase , Reología
2.
Polymers (Basel) ; 15(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37959994

RESUMEN

The destruction of polymers under the influence of ultraviolet (UV) radiation is the cause of their aging and deterioration of strength properties. Asphaltenes are low-value waste products after the refining and deasphalting of heavy crude oil, which absorb UV radiation well. Asphaltenes require rational utilization, which suggests their use as UV stabilizing agents for polymers. In this work, asphaltenes were used to prevent UV aging of polypropylene (PP) by adding them in a mass fraction from 5% to 30% within an asphaltene/PP composite material. Rheometry, calorimetry, X-ray diffraction analysis, and tensile strength of PP films containing asphaltenes were performed before and after their intense UV irradiation for accelerated aging. Asphaltenes slightly reduce the viscosity, crystallinity, and mechanical strength of the initial PP due to their plasticizing effect. However, this deterioration in properties is more than compensated when studying UV-aged samples. Intense UV aging causes multiple catastrophic drops in the viscosity and strength of pure PP with the preservation of crystallinity due to the break of polymer chains and a decrease in molecular weight by approximately eight times. Asphaltenes suppress the destruction of PP, which is expressed in a significantly smaller decline in its viscosity and strength due to UV aging. The most optimal content of asphaltenes is 20%, which suppresses UV destruction by six times and best preserves the strength properties of PP.

3.
Front Immunol ; 14: 1228461, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37600800

RESUMEN

To protect young individuals against SARS-CoV-2 infection, we conducted an open-label, prospective, non-randomised dose-escalation Phase 1/2 clinical trial to evaluate the immunogenicity and safety of the prime-boost "Sputnik V" vaccine administered at 1/10 and 1/5 doses to adolescents aged 12-17 years. The study began with the vaccination of the older cohort (15-to-17-year-old participants) with the lower (1/10) dose of vaccine and then expanded to the whole group (12-to-17-year-old participants). Next, 1/5 dose was used according to the same scheme. Both doses were well tolerated by all age groups. No serious or severe adverse events were detected. Most of the solicited adverse reactions were mild. No significant differences in total frequencies of adverse events were registered between low and high doses in age-pooled groups (69.6% versus 66.7%). In contrast, the 1/5 dose induced significantly higher humoral and T cell-mediated immune responses than the 1/10 dose. The 1/5 vaccine dose elicited higher antigen-binding (both S and RBD-specific) as well as virus-neutralising antibody titres at the maximum of response (day 42), also resulting in a statistically significant difference at a distanced timepoint (day 180) compared to the 1/10 vaccine dose. Higher dose resulted in increased cross-neutralization of Delta and Omicron variants. Clinical Trial Registration: ClinicalTrials.gov, NCT04954092, LP-007632.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Adolescente , Niño , Humanos , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Estudios Prospectivos , SARS-CoV-2
4.
Polymers (Basel) ; 15(15)2023 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-37571137

RESUMEN

The usual problem of meltable phase-change agents is the instability in their form upon heating, which can be solved by placing them into a continuous polymer matrix. Epoxy resin is a suitable medium for dispersing molten agents, but it is necessary to make the obtained droplets stable during the curing of the formed phase-change material. This work shows that molten paraffin wax forms a Pickering emulsion in an epoxy medium and in the presence of asphaltenes extracted from heavy crude oil. Theoretical calculations revealed the complex equilibrium in the epoxy/wax/asphaltene triple system due to their low mutual solubility. Rheological studies showed the viscoplastic behavior of the obtained dispersions at 25 °C, which disappears upon the heating and melting of the paraffin phase. Wax and asphaltenes increased the viscosity of the epoxy medium during its curing but did not inhibit cross-linking or reduce the glass transition temperature of the cured polymer. As a result of curing, it is possible to obtain phase-change materials containing up to 45% paraffin wax that forms a dispersed phase with a size of 0.2-6.5 µm. The small size of dispersed wax can decrease its degree of crystallinity to 13-29% of its original value, reducing the efficiency of the phase-change material.

5.
EMBO J ; 42(10): e113519, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37013908

RESUMEN

Recruitment of RNA polymerase II (Pol II) to promoters is essential for transcription. Despite conflicting evidence, the Pol II preinitiation complex (PIC) is often thought to have a uniform composition and to assemble at all promoters via an identical mechanism. Here, using Drosophila melanogaster S2 cells as a model, we demonstrate that different promoter classes function via distinct PICs. Promoter DNA of developmentally regulated genes readily associates with the canonical Pol II PIC, whereas housekeeping promoters do not, and instead recruit other factors such as DREF. Consistently, TBP and DREF are differentially required by distinct promoter types. TBP and its paralog TRF2 also function at different promoter types in a partially redundant manner. In contrast, TFIIA is required at all promoters, and we identify factors that can recruit and/or stabilize TFIIA at housekeeping promoters and activate transcription. Promoter activation by tethering these factors is sufficient to induce the dispersed transcription initiation patterns characteristic of housekeeping promoters. Thus, different promoter classes utilize distinct mechanisms of transcription initiation, which translate into different focused versus dispersed initiation patterns.


Asunto(s)
Proteínas de Drosophila , Factores de Transcripción , Animales , Factores de Transcripción/genética , Factor de Transcripción TFIIA/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteína de Unión a TATA-Box/genética , Proteína de Unión a TATA-Box/metabolismo , Regiones Promotoras Genéticas , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , Transcripción Genética , Proteínas de Drosophila/genética
6.
Mol Biol Evol ; 40(4)2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36947084

RESUMEN

Aquaporin-mediated oocyte hydration is considered important for the evolution of pelagic eggs and the radiative success of marine teleosts. However, the molecular regulatory mechanisms controlling this vital process are not fully understood. Here, we analyzed >400 piscine genomes to uncover a previously unknown teleost-specific aquaporin-1 cluster (TSA1C) comprised of tandemly arranged aqp1aa-aqp1ab2-aqp1ab1 genes. Functional evolutionary analysis of the TSA1C reveals a ∼300-million-year history of downstream aqp1ab-type gene loss, neofunctionalization, and subfunctionalization, but with marine species that spawn highly hydrated pelagic eggs almost exclusively retaining at least one of the downstream paralogs. Unexpectedly, one-third of the modern marine euacanthomorph teleosts selectively retain both aqp1ab-type channels and co-evolved protein kinase-mediated phosphorylation sites in the intracellular subdomains together with teleost-specific Ywhaz-like (14-3-3ζ-like) binding proteins for co-operative membrane trafficking regulation. To understand the selective evolutionary advantages of these mechanisms, we show that a two-step regulated channel shunt avoids competitive occupancy of the same plasma membrane space in the oocyte and accelerates hydration. These data suggest that the evolution of the adaptive molecular regulatory features of the TSA1C facilitated the rise of pelagic eggs and their subsequent geodispersal in the oceanic currents.


Asunto(s)
Proteínas 14-3-3 , Oocitos , Animales , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Oocitos/metabolismo , Evolución Molecular , Peces/genética , Filogenia
7.
EMBO J ; 42(3): e112100, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36545802

RESUMEN

All multicellular life relies on differential gene expression, determined by regulatory DNA elements and DNA-binding transcription factors that mediate activation and repression via cofactor recruitment. While activators have been extensively characterized, repressors are less well studied: the identities and properties of their repressive domains (RDs) are typically unknown and the specific co-repressors (CoRs) they recruit have not been determined. Here, we develop a high-throughput, next-generation sequencing-based screening method, repressive-domain (RD)-seq, to systematically identify RDs in complex DNA-fragment libraries. Screening more than 200,000 fragments covering the coding sequences of all transcription-related proteins in Drosophila melanogaster, we identify 195 RDs in known repressors and in proteins not previously associated with repression. Many RDs contain recurrent short peptide motifs, which are conserved between fly and human and are required for RD function, as demonstrated by motif mutagenesis. Moreover, we show that RDs that contain one of five distinct repressive motifs interact with and depend on different CoRs, such as Groucho, CtBP, Sin3A, or Smrter. These findings advance our understanding of repressors, their sequences, and the functional impact of sequence-altering mutations and should provide a valuable resource for further studies.


Asunto(s)
Proteínas de Drosophila , Factores de Transcripción , Animales , Humanos , Factores de Transcripción/metabolismo , Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas Represoras/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas Co-Represoras/metabolismo , ADN/metabolismo
8.
Genomics ; 114(4): 110431, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35835427

RESUMEN

Despite recent studies discussing the evolutionary impacts of gene duplications and losses among metazoans, the genomic basis for the evolution of phyla remains enigmatic. Here, we employ phylogenomic approaches to search for orthologous genes without known functions among echinoderms, and subsequently use them to guide the identification of their homologs across other metazoans. Our final set of 14 genes was obtained via a suite of homology prediction tools, gene expression data, gene ontology, and generating the Strongylocentrotus purpuratus phylome. The gene set was subjected to selection pressure analyses, which indicated that they are highly conserved and under negative selection. Their presence across broad taxonomic depths suggests that genes required to form a phylum are ancestral to that phylum. Therefore, rather than de novo gene genesis, we posit that evolutionary forces such as selection on existing genomic elements over large timescales may drive divergence and contribute to the emergence of phyla.


Asunto(s)
Equinodermos , Genoma , Animales , Equinodermos/genética , Evolución Molecular , Duplicación de Gen , Genómica , Filogenia
9.
Nucleic Acids Res ; 50(W1): W623-W632, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35552456

RESUMEN

The Orthology Benchmark Service (https://orthology.benchmarkservice.org) is the gold standard for orthology inference evaluation, supported and maintained by the Quest for Orthologs consortium. It is an essential resource to compare existing and new methods of orthology inference (the bedrock for many comparative genomics and phylogenetic analysis) over a standard dataset and through common procedures. The Quest for Orthologs Consortium is dedicated to maintaining the resource up to date, through regular updates of the Reference Proteomes and increasingly accessible data through the OpenEBench platform. For this update, we have added a new benchmark based on curated orthology assertion from the Vertebrate Gene Nomenclature Committee, and provided an example meta-analysis of the public predictions present on the platform.


Asunto(s)
Benchmarking , Genómica , Filogenia , Genómica/métodos , Proteoma
10.
Genes (Basel) ; 12(10)2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34681040

RESUMEN

Functional annotation allows adding biologically relevant information to predicted features in genomic sequences, and it is, therefore, an important procedure of any de novo genome sequencing project. It is also useful for proofreading and improving gene structural annotation. Here, we introduce FA-nf, a pipeline implemented in Nextflow, a versatile computational workflow management engine. The pipeline integrates different annotation approaches, such as NCBI BLAST+, DIAMOND, InterProScan, and KEGG. It starts from a protein sequence FASTA file and, optionally, a structural annotation file in GFF format, and produces several files, such as GO assignments, output summaries of the abovementioned programs and final annotation reports. The pipeline can be broken easily into smaller processes for the purpose of parallelization and easily deployed in a Linux computational environment, thanks to software containerization, thus helping to ensure full reproducibility.


Asunto(s)
Genoma/genética , Anotación de Secuencia Molecular/métodos , Programas Informáticos , Mapeo Cromosómico , Biología Computacional , Genómica
11.
Nat Commun ; 12(1): 6078, 2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34667177

RESUMEN

The C-terminal domain (CTD) of the largest subunit of RNA polymerase II (Pol II) is a regulatory hub for transcription and RNA processing. Here, we identify PHD-finger protein 3 (PHF3) as a regulator of transcription and mRNA stability that docks onto Pol II CTD through its SPOC domain. We characterize SPOC as a CTD reader domain that preferentially binds two phosphorylated Serine-2 marks in adjacent CTD repeats. PHF3 drives liquid-liquid phase separation of phosphorylated Pol II, colocalizes with Pol II clusters and tracks with Pol II across the length of genes. PHF3 knock-out or SPOC deletion in human cells results in increased Pol II stalling, reduced elongation rate and an increase in mRNA stability, with marked derepression of neuronal genes. Key neuronal genes are aberrantly expressed in Phf3 knock-out mouse embryonic stem cells, resulting in impaired neuronal differentiation. Our data suggest that PHF3 acts as a prominent effector of neuronal gene regulation by bridging transcription with mRNA decay.


Asunto(s)
Neuronas/metabolismo , ARN Polimerasa II/química , ARN Polimerasa II/metabolismo , ARN , Factores de Transcripción/metabolismo , Animales , Línea Celular , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Ratones Noqueados , Neuronas/química , Fosforilación , Dominios Proteicos , ARN/química , ARN/genética , ARN/metabolismo , ARN Polimerasa II/genética , Procesamiento Postranscripcional del ARN , Estabilidad del ARN , Factores de Transcripción/genética , Transcripción Genética
12.
Biochim Biophys Acta Gen Subj ; 1865(1): 129762, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33053413

RESUMEN

BACKGROUND: Previous studies have demonstrated the formation of stable complexes between inorganic pyrophosphatase (PPase) and three other Escherichia coli enzymes - cupin-type phosphoglucose isomerase (cPGI), class I fructose-1,6-bisphosphate aldolase (FbaB) and l-glutamate decarboxylase (GadA). METHODS: Here, we determined by activity measurements how complex formation between these enzymes affects their activities and oligomeric structure. RESULTS: cPGI activity was modulated by all partner proteins, but none was reciprocally affected by cPGI. PPase activity was down-regulated upon complex formation, whereas all other enzymes were up-regulated. For cPGI, the activation was partially counteracted by a shift in dimer ⇆ hexamer equilibrium to inactive hexamer. Complex stoichiometry appeared to be 1:1 in most cases, but FbaB formed both 1:1 and 1:2 complexes with both GadA and PPase, FbaB activation was only observed in the 1:2 complexes. FbaB and GadA induced functional asymmetry (negative kinetic cooperativity) in hexameric PPase, presumably by favoring partial dissociation to trimers. CONCLUSIONS: These four enzymes form all six possible binary complexes in vitro, resulting in modulated activity of at least one of the constituent enzymes. In five complexes, the effects on activity were unidirectional, and in one complex (FbaB⋅PPase), the effects were reciprocal. The effects of potential physiological significance include inhibition of PPase by FbaB and GadA and activation of FbaB and cPGI by PPase. Together, they provide a mechanism for feedback regulation of FbaB and GadA biosynthesis. GENERAL SIGNIFICANCE: These findings indicate the complexity of functionally significant interactions between cellular enzymes, which classical enzymology treats as individual entities, and demonstrate their moonlighting activities as regulators.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Fructosa-Bifosfato Aldolasa/metabolismo , Glucosa-6-Fosfato Isomerasa/metabolismo , Glutamato Descarboxilasa/metabolismo , Pirofosfatasa Inorgánica/metabolismo , Proteínas de la Membrana/metabolismo , Escherichia coli/química , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/química , Fructosa-Bifosfato Aldolasa/química , Glucosa-6-Fosfato Isomerasa/química , Glutamato Descarboxilasa/química , Humanos , Pirofosfatasa Inorgánica/química , Cinética , Proteínas de la Membrana/química , Multimerización de Proteína
13.
Genome Biol ; 21(1): 275, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33168033

RESUMEN

BACKGROUND: The Mediterranean mussel Mytilus galloprovincialis is an ecologically and economically relevant edible marine bivalve, highly invasive and resilient to biotic and abiotic stressors causing recurrent massive mortalities in other bivalves. Although these traits have been recently linked with the maintenance of a high genetic variation within natural populations, the factors underlying the evolutionary success of this species remain unclear. RESULTS: Here, after the assembly of a 1.28-Gb reference genome and the resequencing of 14 individuals from two independent populations, we reveal a complex pan-genomic architecture in M. galloprovincialis, with a core set of 45,000 genes plus a strikingly high number of dispensable genes (20,000) subject to presence-absence variation, which may be entirely missing in several individuals. We show that dispensable genes are associated with hemizygous genomic regions affected by structural variants, which overall account for nearly 580 Mb of DNA sequence not included in the reference genome assembly. As such, this is the first study to report the widespread occurrence of gene presence-absence variation at a whole-genome scale in the animal kingdom. CONCLUSIONS: Dispensable genes usually belong to young and recently expanded gene families enriched in survival functions, which might be the key to explain the resilience and invasiveness of this species. This unique pan-genome architecture is characterized by dispensable genes in accessory genomic regions that exceed by orders of magnitude those observed in other metazoans, including humans, and closely mirror the open pan-genomes found in prokaryotes and in a few non-metazoan eukaryotes.


Asunto(s)
Genoma , Mytilus/genética , Animales , Secuencia de Bases , Evolución Biológica , Femenino , Genómica , Humanos , Inmunidad Innata , Masculino , Mytilus/anatomía & histología , Factor 1 de Elongación Peptídica , Proteínas Citotóxicas Formadoras de Poros
14.
Pharmacol Res ; 161: 105249, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33068730

RESUMEN

The molecular complexity of human breast cancer (BC) renders the clinical management of the disease challenging. Long non-coding RNAs (lncRNAs) are promising biomarkers for BC patient stratification, early detection, and disease monitoring. Here, we identified the involvement of the long intergenic non-coding RNA 01087 (LINC01087) in breast oncogenesis. LINC01087 appeared significantly downregulated in triple-negative BCs (TNBCs) and upregulated in the luminal BC subtypes in comparison to mammary samples from cancer-free women and matched normal cancer pairs. Interestingly, deregulation of LINC01087 allowed to accurately distinguish between luminal and TNBC specimens, independently of the clinicopathological parameters, and of the histological and TP53 or BRCA1/2 mutational status. Moreover, increased expression of LINC01087 predicted a better prognosis in luminal BCs, while TNBC tumors that harbored lower levels of LINC01087 were associated with reduced relapse-free survival. Furthermore, bioinformatics analyses were performed on TNBC and luminal BC samples and suggested that the putative tumor suppressor activity of LINC01087 may rely on interferences with pathways involved in cell survival, proliferation, adhesion, invasion, inflammation and drug sensitivity. Altogether, these data suggest that the assessment of LINC01087 deregulation could represent a novel, specific and promising biomarker not only for the diagnosis and prognosis of luminal BC subtypes and TNBCs, but also as a predictive biomarker of pharmacological interventions.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , ARN Largo no Codificante/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Biomarcadores de Tumor/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Células MCF-7 , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Supervivencia sin Progresión , Mapas de Interacción de Proteínas , ARN Largo no Codificante/genética , Transducción de Señal , Factores de Tiempo , Transcriptoma , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología
15.
Genome Res ; 30(7): 1047-1059, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32759341

RESUMEN

We have produced RNA sequencing data for 53 primary cells from different locations in the human body. The clustering of these primary cells reveals that most cells in the human body share a few broad transcriptional programs, which define five major cell types: epithelial, endothelial, mesenchymal, neural, and blood cells. These act as basic components of many tissues and organs. Based on gene expression, these cell types redefine the basic histological types by which tissues have been traditionally classified. We identified genes whose expression is specific to these cell types, and from these genes, we estimated the contribution of the major cell types to the composition of human tissues. We found this cellular composition to be a characteristic signature of tissues and to reflect tissue morphological heterogeneity and histology. We identified changes in cellular composition in different tissues associated with age and sex, and found that departures from the normal cellular composition correlate with histological phenotypes associated with disease.


Asunto(s)
Transcripción Genética , Línea Celular , Células Endoteliales/metabolismo , Células Epiteliales/metabolismo , Femenino , Perfilación de la Expresión Génica , Ginecomastia/genética , Ginecomastia/metabolismo , Humanos , Masculino , Mesodermo/citología , Mesodermo/metabolismo , Neoplasias/genética , Especificidad de Órganos , Análisis de Secuencia de ARN
16.
Br J Cardiol ; 27(1): 03, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-35747425

RESUMEN

This short review of cardiac tumours presents a case that clearly demonstrates the manifestation of embolic and cardiac symptoms of an intracardiac mass. Acute onset and rapid progression of a neoplastic process in the heart leading to arrhythmia, cardiac conduction disorders and heart failure combined with highly mobile fragments of tumour, which can cause emboli in cerebral vessels, are characteristic signs of an intracardiac mass. Early diagnosis and immediate treatment may improve the long-term prognosis, but overall the prognosis is poor. Cardiac tumours present to the cardiologist when the patient presents with cardiac symptoms, and the neurologist when there are cerebral symptoms. Most cardiac masses are not amenable to percutaneous biopsy; therefore, definitive diagnosis often awaits surgical excision.

17.
Plant J ; 101(2): 455-472, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31529539

RESUMEN

We sequenced the genome of the highly heterozygous almond Prunus dulcis cv. Texas combining short- and long-read sequencing. We obtained a genome assembly totaling 227.6 Mb of the estimated almond genome size of 238 Mb, of which 91% is anchored to eight pseudomolecules corresponding to its haploid chromosome complement, and annotated 27 969 protein-coding genes and 6747 non-coding transcripts. By phylogenomic comparison with the genomes of 16 additional close and distant species we estimated that almond and peach (Prunus persica) diverged around 5.88 million years ago. These two genomes are highly syntenic and show a high degree of sequence conservation (20 nucleotide substitutions per kb). However, they also exhibit a high number of presence/absence variants, many attributable to the movement of transposable elements (TEs). Transposable elements have generated an important number of presence/absence variants between almond and peach, and we show that the recent history of TE movement seems markedly different between them. Transposable elements may also be at the origin of important phenotypic differences between both species, and in particular for the sweet kernel phenotype, a key agronomic and domestication character for almond. Here we show that in sweet almond cultivars, highly methylated TE insertions surround a gene involved in the biosynthesis of amygdalin, whose reduced expression has been correlated with the sweet almond phenotype. Altogether, our results suggest a key role of TEs in the recent history and diversification of almond and its close relative peach.


Asunto(s)
Secuencia de Bases , Elementos Transponibles de ADN/genética , Genoma de Planta , Prunus dulcis/genética , Prunus persica/genética , Mapeo Cromosómico , Metilación de ADN , Domesticación , Evolución Molecular , Genes de Plantas/genética , Filogenia , Semillas , Especificidad de la Especie
19.
Analyst ; 144(1): 152-156, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30489574

RESUMEN

In this study, Fe3O4-based composite magnetic nanoparticles were found to separate volatile compounds directly in the gas phase for the first time. The phenomenon of H2Se sorption on the magnetic nanoparticles was studied in detail and applied for separation and preconcentration. The developed approach was applied for the determination of selenium in dietary supplement samples after microwave digestion by ETA-AAS as a proof-of-concept example.

20.
EMBO J ; 37(16)2018 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-30006452

RESUMEN

Even though transcription factors (TFs) are central players of gene regulation and have been extensively studied, their regulatory trans-activation domains (tADs) often remain unknown and a systematic functional characterization of tADs is lacking. Here, we present a novel high-throughput approach tAD-seq to functionally test thousands of candidate tADs from different TFs in parallel. The tADs we identify by pooled screening validate in individual luciferase assays, whereas neutral regions do not. Interestingly, the tADs are found at arbitrary positions within the TF sequences and can contain amino acid (e.g., glutamine) repeat regions or overlap structured domains, including helix-loop-helix domains that are typically annotated as DNA-binding. We also identified tADs in the non-native reading frames, confirming that random sequences can function as tADs, albeit weakly. The identification of tADs as short protein sequences sufficient for transcription activation will enable the systematic study of TF function, which-particularly for TFs of different transcription activating functionalities-is still poorly understood.


Asunto(s)
Proteínas de Drosophila , Transactivadores , Transcripción Genética , Animales , Línea Celular , Proteínas de Drosophila/biosíntesis , Proteínas de Drosophila/genética , Drosophila melanogaster , Dominios Proteicos , Transactivadores/biosíntesis , Transactivadores/genética
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