RESUMEN
Helitrons are widespread eukaryotic DNA transposons that have significantly contributed to genome variability and evolution, in part because of their distinctive, replicative rolling-circle mechanism, which often mobilizes adjacent genes. Although most eukaryotic transposases form oligomers and use RNase H-like domains to break and rejoin double-stranded DNA (dsDNA), Helitron transposases contain a single-stranded DNA (ssDNA)-specific HUH endonuclease domain. Here, we report the cryo-electron microscopy structure of a Helitron transposase bound to the 5'-transposon end, providing insight into its multidomain architecture and function. The monomeric transposase forms a tightly packed assembly that buries the covalently attached cleaved end, protecting it until the second end becomes available. The structure reveals unexpected architectural similarity to TraI, a bacterial relaxase that also catalyzes ssDNA movement. The HUH active site suggests how two juxtaposed tyrosines, a feature of many replication initiators that use HUH nucleases, couple the conformational shift of an α-helix to control strand cleavage and ligation reactions.
Asunto(s)
Quirópteros/metabolismo , Elementos Transponibles de ADN , ADN de Cadena Simple/metabolismo , Transposasas/metabolismo , Animales , Dominio Catalítico , Quirópteros/genética , Microscopía por Crioelectrón , ADN de Cadena Simple/genética , ADN de Cadena Simple/ultraestructura , Células HEK293 , Humanos , Modelos Moleculares , Conformación de Ácido Nucleico , Conformación Proteica en Hélice alfa , Dominios y Motivos de Interacción de Proteínas , Relación Estructura-Actividad , Transposasas/genética , Transposasas/ultraestructura , TirosinaRESUMEN
BACKGROUND: Breeding for new maize varieties with propitious root systems has tremendous potential in improving water and nutrients use efficiency and plant adaptation under suboptimal conditions. To date, most of the previously detected root-related trait genes in maize were new without functional verification. In this study, seven seedling root architectural traits were examined at three developmental stages in a recombinant inbred line population (RIL) of 179 RILs and a genome-wide association study (GWAS) panel of 80 elite inbred maize lines through quantitative trait loci (QTL) mapping and genome-wide association study. RESULTS: Using inclusive composite interval mapping, 8 QTLs accounting for 6.44-8.83 % of the phenotypic variation in root traits, were detected on chromosomes 1 (qRDWv3-1-1 and qRDW/SDWv3-1-1), 2 (qRBNv1-2-1), 4 (qSUAv1-4-1, qSUAv2-4-1, and qROVv2-4-1), and 10 (qTRLv1-10-1, qRBNv1-10-1). GWAS analysis involved three models (EMMAX, FarmCPU, and MLM) for a set of 1,490,007 high-quality single nucleotide polymorphisms (SNPs) obtained via whole genome next-generation sequencing (NGS). Overall, 53 significant SNPs with a phenotypic contribution rate ranging from 5.10 to 30.2 % and spread all over the ten maize chromosomes exhibited associations with the seven root traits. 17 SNPs were repeatedly detected from at least two growth stages, with several SNPs associated with multiple traits stably identified at all evaluated stages. Within the average linkage disequilibrium (LD) distance of 5.2 kb for the significant SNPs, 46 candidate genes harboring substantial SNPs were identified. Five potential genes viz. Zm00001d038676, Zm00001d015379, Zm00001d018496, Zm00001d050783, and Zm00001d017751 were verified for expression levels using maize accessions with extreme root branching differences from the GWAS panel and the RIL population. The results showed significantly (P < 0.001) different expression levels between the outer materials in both panels and at all considered growth stages. CONCLUSIONS: This study provides a key reference for uncovering the complex genetic mechanism of root development and genetic enhancement of maize root system architecture, thus supporting the breeding of high-yielding maize varieties with propitious root systems.
Asunto(s)
Plantones , Zea mays , Estudio de Asociación del Genoma Completo , Fenotipo , Fitomejoramiento , Polimorfismo de Nucleótido Simple , Plantones/genética , Zea mays/genéticaRESUMEN
The electronic structure of the alloyed transition-metal phosphorus trichalcogenide van der Waals Fe1-xNixPS3 compounds is studied using X-ray absorption spectroscopy and resonant photoelectron spectroscopy combined with intensive density functional theory calculations. Our systematic spectroscopic and theoretical data demonstrate the strong localization of the Fe- and Ni-ions-derived electronic states that leads to the description of the spectroscopic data as belonging simultaneously to Mott-Hubbard and charge-transfer insulators. These findings reveal Fe1-xNixPS3 as unique layered compounds with dual character of the insulating state, pointing to the importance of these results for the description and understanding of the functionality of this class of materials in different applications.
RESUMEN
The integration of graphene in spintronics applications requires its close contact with ferromagnetic materials, promoting effective spin injection. At the same time, the linear energy vs wave-vector dependence for the charge carriers in the vicinity of the Fermi level for graphene has to be conserved. Here, motivated by recent theoretical predictions, we present the experimental realization on the synthesis of graphene/ferromagnetic-Mn5Ge3/semiconducting-Ge heterostructures using the intercalation of Mn in the epitaxial graphene/Ge interfaces. Different in situ and ex situ methods confirm the formation of such heterosystems, where graphene is in close contact with ferromagnetic Mn5Ge3, as the Curie temperature reaches room temperature. Despite the expected small distance between graphene and Mn5Ge3 causing the strong interaction at interfaces, our angle-resolved photoelectron spectroscopy experiments for the formed graphene/Mn5Ge3 interfaces confirm the linear band dispersion around the Fermi level for the carriers in graphene. These findings open up an interesting perspective for the integration of graphene in modern semiconductor technology with possible implications for spintronics device fabrication.
RESUMEN
PURPOSE: This study aims to translate the English version of the Trans Woman Voice Questionnaire (TWVQ) to simplified Chinese (TWVQ-SC) and to examine its reliability and validity. METHOD: Standardized translation procedures were strictly followed for the translation of the TWVQ. Two hundred sixty trans woman and 128 cis woman subjects completed sociodemographic investigation, the TWVQ-SC, and the Voice Handicap Index-10 (VHI-10) online. Internal consistency was examined by Cronbach reliability coefficient (Cronbach α). Test-retest reliability was quantified by intraclass correlation coefficient (ICC). Content validity, structural validity, and discriminant validity were examined by expert panel's judgment, factor analysis, Spearman's rank correlation coefficient, and the Mann-Whitney U test. RESULTS: The Cronbach α of the TWVQ-SC was .969 and the ICC was .841, indicating excellent internal consistency and good test-retest reliability. The four principal factors explained 21.345%, 18.592%, 13.551%, and 12.027% of the variance respectively with the cumulative contribution rate 65.514%. There was a strong correlation between the total score of the TWVQ-SC and that of the VHI-10 (r = .858, p < .001), indicating good structural validity. The total score of the TWVQ-SC of the trans woman subjects was significantly higher than that of the cis woman subjects (z = 14.590, p < .05), indicating good discriminant validity. CONCLUSION: The TWVQ-SC exhibits overall high reliability and validity, qualified to be applied as a reliable clinical tool to evaluate trans women's voice in mainland China.
Asunto(s)
Evaluación de la Discapacidad , Traducciones , China , Femenino , Humanos , Psicometría , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
Large-scale high-quality van der Waals CoPS3 single crystals are synthesized using a chemical vapor transport (CVT) method. The crystallographic structure and electronic properties of this layered material are systematically studied using different spectroscopic methods (XPS, NEXAFS, and resonant photoelectron spectroscopy) accompanied by density functional theory (DFT) calculations. All experimental and theoretical data allow assignment of this material to the class of mixed Mott-Hubbard/charge-transfer insulator with Udd â Δ. All obtained results can enrich the information on the new class of van der Waals materials, transition metal phosphorus trichalcogenides, and help to further effectively exploit their electronic, optical, and transport properties, which are important for adopting this kind of materials into different application areas, such as spintronics and catalysis.
RESUMEN
Fascin actin-bundling protein 1 (FSCN1) is an actin-bundling protein that is capable of inducing membrane protrusions and plays critical roles in cell migration, motility, adhesion, and other cellular interactions. FSCN1 also plays a role in forming and stabilizing filopodia or microspikes, which assist during cell migration. Furthermore, FSCN1 is a downstream target of several microRNAs and participates in various biological processes, such as epithelial-to-mesenchymal transition and autophagy, which regulate the invasion and migration ability of cells in various cancers. Increased FSCN1 levels have been associated with enhanced migration and invasion of multiple cancers as well as poor patient prognosis. Promising results from in vitro experimental studies using docosahexaenoic acid (DHA) in breast cancer and recombinant porcine NK-lysin A in hepatocellular carcinoma have revealed that anticancer drugs targeting FSCN1 have significant potential clinical applications. This review discusses FSCN1 in terms of five aspects: structure and function, biological processes, regulatory mechanisms, clinical applications, and future prospects.
RESUMEN
Maize (Zea mays L.) is a tropical crop, and low temperature has become one of the main abiotic stresses for maize growth and development, affecting many maize growth processes. The main area of maize production in China, Jilin province, often suffers from varying degrees of cold damage in spring, which seriously affects the quality and yield of maize. In the face of global climate change and food security concerns, discovering cold tolerance genes, developing cold tolerance molecular markers, and creating cold-tolerant germplasm have become urgent for improving maize resilience against these conditions and obtaining an increase in overall yield. In this study, whole-genome sequencing and genotyping by sequencing were used to perform genome-wide association analysis (GWAS) and quantitative trait locus (QTL) mapping of the two populations, respectively. Overall, four single-nucleotide polymorphisms (SNPs) and 12 QTLs were found to be significantly associated with cold tolerance. Through joint analysis, an intersection of GWAS and QTL mapping was found on chromosome 3, on which the Zm00001d002729 gene was identified as a potential factor in cold tolerance. We verified the function of this target gene through overexpression, suppression of expression, and genetic transformation into maize. We found that Zm00001d002729 overexpression resulted in better cold tolerance in this crop. The identification of genes associated with cold tolerance contributes to the clarification of the underlying mechanism of this trait in maize and provides a foundation for the adaptation of maize to colder environments in the future, to ensure food security.
RESUMEN
Acoustic devices are widely applied in telephone communication, human-computer voice interaction systems, medical ultrasound examination, and other applications. However, traditional acoustic devices are hard to integrate into a flexible system and therefore it is necessary to fabricate light weight and flexible acoustic devices for audible sound generation and detection. Recent advances in acoustic devices have greatly overcome the limitations of conventional acoustic sensors in terms of sensitivity, tunability, photostability, and in vivo applicability by employing nanomaterials. In this review, light weight and flexible nanomaterial-enabled acoustic devices (NEADs) including sound generators and sound detectors are covered. Additionally, the fundamental concepts of acoustic as well as the working principle of the NEAD are introduced in detail. Also, the structures of future acoustic devices, such as flexible earphones and microphones, are forecasted. Further exploration of flexible acoustic devices is a key priority and will have a great impact on the advancement of intelligent robot-human interaction and flexible electronics.
RESUMEN
The objective of this study was to evaluate the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation to ewes during late gestation on finishing lamb liver and adipose tissue fatty acid (FA) profile and gene expression. Lambs born from ewes supplemented with Ca salts of EPA + DHA, or palm FA distillate (PFAD) high in palmitic and oleic acid at 0.39% DM during the last 50 d of gestation were used. Lambs were weaned at 61 d of age and adapted to a high concentrate diet for 1.5 mo. After adaptation, 74 lambs (28 pens) were blocked by sex and BW and used in a 2 × 2 factorial arrangement of treatments using the factors of dam supplementation (DS) and lamb supplementation (LS) of Ca salts of EPA + DHA or PFAD at 1.48% DM. Lambs were slaughtered after 42 d and liver and adipose tissue collected for FA and gene expression analysis. Liver concentrations of EPA and DHA were greater (P < 0.01) with LS of EPA + DHA vs. PFAD during the finishing period. In adipose tissue, a lamb × dam interaction was observed for EPA (P = 0.02) and DHA (P = 0.04); LS of EPA + DHA increased EPA and DHA, but the increase was greatest in lambs born from ewes supplemented with PFAD. No lamb × dam treatment interactions were observed for gene expression in liver tissue (P > 0.10). Hepatic mRNA abundance of hormone-sensitive lipase (HSL; P = 0.01) was greater in lambs born from EPA + DHA ewes vs. lambs from PFAD ewes. mRNA expression of stearoyl-CoA desaturase (P < 0.01), fatty acid synthase (P = 0.01), Δ5-desaturase (P < 0.01), and Δ6-desaturase (P < 0.01) were decreased in liver of EPA + DHA lambs. A significant lamb × dam diet interaction was observed for elongation of very long chain fatty acid 2 in adipose tissue (P = 0.01); lambs supplemented with the same FA as their dams had lower expression. Expression of HSL tended (P = 0.08) to be decreased in adipose of EPA + DHA lambs born from EPA + DHA ewes. The changes in mRNA expression suggest that lipogenesis decreased, and lipolysis increased in lamb liver with EPA + DHA vs. PFAD supplementation during the finishing period. In adipose tissue, changes suggest that lipogenesis decreased in lambs born from EPA + DHA supplemented dams and supplemented with EPA + DHA during the finishing period. In addition, these results suggest an interaction between supplementation of FA to dams during late gestation on lamb response of adipose tissue, but not liver, to FA supplementation during the finishing period.