The long noncoding RNA COLDAIR is necessary for the repression of a floral repressor FLOWERING LOCUS C (FLC) during vernalization in Arabidopsis thaliana. The repression of FLC is mediated by ...increased enrichment of Polycomb Repressive Complex 2 (PRC2) and subsequent trimethylation of Histone H3 Lysine 27 (H3K27me3) at FLC chromatin. In this study we found that the association of COLDAIR with chromatin occurs only at the FLC locus and that the central region of the COLDAIR transcript is critical for this interaction. A modular motif in COLDAIR is responsible for the association with PRC2 in vitro, and the mutations within the motif that reduced the association of COLDAIR with PRC2 resulted in vernalization insensitivity. The vernalization insensitivity caused by mutant COLDAIR was rescued by the ectopic expression of the wild-type COLDAIR. Our study reveals the molecular framework in which COLDAIR lncRNA mediates the PRC2-mediated repression of FLC during vernalization.
Long noncoding RNAs (lncRNAs) affect gene regulation through structural and regulatory interactions with associated proteins. The Polycomb complex often binds to lncRNAs in eukaryotes, and an lncRNA, ...COLDAIR, associates with Polycomb to mediate silencing of the floral repressor FLOWERING LOCUS C (FLC) during the process of vernalization in Arabidopsis. Here, we identified an additional Polycomb-binding lncRNA, COLDWRAP. COLDWRAP is derived from the repressed promoter of FLC and is necessary for the establishment of the stable repressed state of FLC by vernalization. Both COLDAIR and COLDWRAP are required to form a repressive intragenic chromatin loop at the FLC locus by vernalization. Our results indicate that vernalization-mediated Polycomb silencing is coordinated by lncRNAs in a cooperative manner to form a stable repressive chromatin structure.
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•A long encoding RNA, COLDWRAP, is transcribed from the repressed FLC promoter•COLDWRAP is necessary for vernalization-mediated FLC silencing•FLC silencing by vernalization includes the formation of an intragenic chromatin loop•lncRNAs and PRC2 are necessary for the formation of an intragenic chromatin loop
Flowering control occurs in part through repression of FLOWERING LOCUS C (FLC). Kim and Sung identify an FLC promoter-derived noncoding RNA (COLDWRAP) that is induced by vernalization and functions with the lncRNA COLDAIR to retain Polycomb at the FLC promoter through the formation of a repressive intragenic chromatin loop.
Human sweat contains vast physiological information, which has been a promising resource for on‐body and real‐time health monitoring. Wearable sweat sensors have recently attracted an ever‐increasing ...interest due to their promising capabilities for continuously tracking changes in health status. However, the commercialization of sweat sensors is seriously hindered by drawbacks of materials including high manufacturing and consumables costs, complex integration technology, as well as limited electrochemical signal transduction. In this review, sweat sensing principles are elaborately interpreted, and the latest advances in functional materials for biomarkers sensing in sweat are systematically summarized. Subsequently, the complex structure–activity relationships between various functional materials and sensing capabilities are further elucidated by coupling chemical structures, geometrics, electrochemical properties, and approaches for materials manufacturing. Furthermore, the integration of each component into sensing device for sweat detection and analysis is also discussed. Finally, challenges and opportunities for wearable sweat sensors are delineated in the development of future personalized and predictive healthcare.
Wearable electrochemical sweat sensors have emerged as a type of promising electronic device for continuous monitoring human health. This article reviews the recent progress on various materials for electrochemical sweat sensing. Structure‐activity relationships of sensing materials, approaches for materials manufacturing, and integration of devices are discussed. Challenges and future research directions are also identified.
Mutation in myostatin (
), a negative regulator of muscle growth in skeletal muscle, resulted in increased muscle mass in mammals and fishes. However,
mutation in avian species has not been reported. ...The objective of this study was to generate
mutation in quail and investigate the effect of
mutation in avian muscle growth. Recently, a new targeted gene knockout approach for the avian species has been developed using an adenoviral CRISPR/Cas9 system. By injecting the recombinant adenovirus containing CRISPR/Cas9 into the quail blastoderm, potential germline chimeras were generated and offspring with three base-pair deletion in the targeted region of the
gene was identified. This non-frameshift mutation in
resulted in deletion of cysteine 42 in the MSTN propeptide region and homozygous mutant quail showed significantly increased body weight and muscle mass with muscle hyperplasia compared to heterozygous mutant and wild-type quail. In addition, decreased fat pad weight and increased heart weight were observed in
mutant quail in an age- and sex-dependent manner, respectively. Taken together, these data indicate anti-myogenic function of
in the avian species and the importance of cysteine 42 in regulating
function.
Heteroatom doping can endow graphene with various new or improved electromagnetic, physicochemical, optical, and structural properties. This greatly extends the arsenal of graphene materials and ...their potential for a spectrum of applications. Considering the latest developments, we comprehensively and critically discuss the syntheses, properties and emerging applications of the growing family of heteroatom-doped graphene materials. The advantages, disadvantages, and preferential doping features of current synthesis approaches are compared, aiming to provide clues for developing new and controllable synthetic routes. We emphasize the distinct properties resulting from various dopants, different doping levels and configurations, and synergistic effects from co-dopants, hoping to assist a better understanding of doped graphene materials. The mechanisms underlying their advantageous uses for energy storage, energy conversion, sensing, and gas storage are highlighted, aiming to stimulate more competent applications.
Recent Advances in Aptamer Sensors Shaban, Samy M; Kim, Dong-Hwan
Sensors (Basel, Switzerland),
02/2021, Letnik:
21, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Recently, aptamers have attracted attention in the biosensing field as signal recognition elements because of their high binding affinity toward specific targets such as proteins, cells, small ...molecules, and even metal ions, antibodies for which are difficult to obtain. Aptamers are single oligonucleotides generated by in vitro selection mechanisms via the systematic evolution of ligand exponential enrichment (SELEX) process. In addition to their high binding affinity, aptamers can be easily functionalized and engineered, providing several signaling modes such as colorimetric, fluorometric, and electrochemical, in what are known as aptasensors. In this review, recent advances in aptasensors as powerful biosensor probes that could be used in different fields, including environmental monitoring, clinical diagnosis, and drug monitoring, are described. Advances in aptamer-based colorimetric, fluorometric, and electrochemical aptasensing with their advantages and disadvantages are summarized and critically discussed. Additionally, future prospects are pointed out to facilitate the development of aptasensor technology for different targets.
Current‐induced control of magnetization in ferromagnets using spin–orbit torque (SOT) has drawn attention as a new mechanism for fast and energy efficient magnetic memory devices. Energy‐efficient ...spintronic devices require a spin‐current source with a large SOT efficiency (ξ) and electrical conductivity (σ), and an efficient spin injection across a transparent interface. Herein, single crystals of the van der Waals (vdW) topological semimetal WTe2 and vdW ferromagnet Fe3GeTe2 are used to satisfy the requirements in their all‐vdW‐heterostructure with an atomically sharp interface. The results exhibit values of ξ ≈ 4.6 and σ ≈ 2.25 × 105 Ω‐1 m‐1 for WTe2. Moreover, the significantly reduced switching current density of 3.90 × 106 A cm−2 at 150 K is obtained, which is an order of magnitude smaller than those of conventional heavy‐metal/ferromagnet thin films. These findings highlight that engineering vdW‐type topological materials and magnets offers a promising route to energy‐efficient magnetization control in SOT‐based spintronics.
All‐van der Waals (vdW) heterostructure with an atomically sharp interface based on topological semimetal shows spin–orbit torque (SOT)‐driven magnetization switching. These findings highlight that engineering vdW‐type topological materials and magnets offers a promising route to energy‐efficient magnetization control in SOT‐based spintronics.
Summary
Vernalization accelerates flowering after prolonged winter cold. Transcriptional and epigenetic changes are known to be involved in the regulation of the vernalization response. Despite ...intensive applications of next‐generation sequencing in diverse aspects of plant research, genome‐wide transcriptome and epigenome profiling during the vernalization response has not been conducted. In this work, to our knowledge, we present the first comprehensive analyses of transcriptomic and epigenomic dynamics during the vernalization process in Arabidopsis thaliana. Six major clusters of genes exhibiting distinctive features were identified. Temporary changes in histone H3K4me3 levels were observed that likely coordinate photosynthesis and prevent oxidative damage during cold exposure. In addition, vernalization induced a stable accumulation of H3K27me3 over genes encoding many development‐related transcription factors, which resulted in either inhibition of transcription or a bivalent status of the genes. Lastly, FLC‐like and VIN3‐like genes were identified that appear to be novel components of the vernalization pathway.
Significance Statement
Our work provides the first comprehensive assessment of transcriptome and epigenome dynamics during the vernalization process and indicates that multiple regulatory pathways are involved in promoting differentiation and phase transitions during vernalization in Arabidopsis.
Two-dimensional graphite-like carbon nitride nanosheets (g-C3N4 NSs) were hybridized with gold nanoparticles (Au NPs) to construct an electrochemiluminescence (ECL) immunosensor. The prepared Au ...NP-functionalized g-C3N4 NS nanohybrids (Au-g-C3N4 NHs) exhibit strong and stable cathodic ECL activity compared to g-C3N4 NSs due to the important roles of Au NPs in trapping and storing the electrons from the conduction band of g-C3N4 NSs, as well as preventing high energy electron-induced passivation of g-C3N4 NSs. On the basis of the improved ECL stability and ECL peak intensity of the Au-g-C3N4 NHs, a novel ECL immunosensor was developed to detect carcinoembryonic antigen (CEA) as a model target analyte. The ECL immunosensor has a sensitive response to CEA in a linear range of 0.02–80 ng mL–1 with a detection limit of 6.8 pg mL–1. Additionally, the proposed immunosensor shows high specificity, good reproducibility, and long-term stability.
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