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Abstract: Apolipoprotein B (ApoB) is a major protein component of plasma lipoproteins. It is involved in many important biological processes such as lipid transportation, enzyme activity regulation, and receptor recognition. [...]

Despite the advantages of the fiber‐shaped Zn‐ion microbattery (FZMB) in powering wearable electronics, several fundamental challenges hinder its practical application, mainly including dendrite growth on Zn anodes (leading to short cycle life) and low electrical conductivity of cathode (resulting in poor rate performance). Herein, a facile approach of sputtering a nano‐thin conductive carbon layer on Zn anode to effectively suppress dendrite growth and a dual‐conductive polymer strategy to fabricate ultraconductive core‐sheath fiber cathode (poly(3,4‐ethylenedioxythiophene)‐poly(styrene sulfonate) (PEDOT:PSS) fiber@polyaniline nanobulges) are demonstrated. The carbon layer suppresses Zn dendrites by uniformizing surface electric field and providing abundant nucleation sites. The superior conductivity of the cathode is inherited from two conductive polymers (in particular, PEDOT:PSS fibers have an ultrahigh conductivity of 3676 S cm−1) and their strong intermolecular interactions. The resulting FZMB shows excellent stability (over 100% capacity retention after 3000 cycles) and supercapacitor‐level rate performance (73% capacity retention from 0.1 to 10 A g−1). Kinetics and mechanism studies reveal that the surface‐controlled dual‐ion migration mechanism is also correlated with the high rate performance. The corresponding quasi‐solid‐state device exhibits high stability under extreme deformation conditions and superior water‐proof capability (94.6% capacity retention after 12 h underwater immersion), demonstrating great practical application potential. [ABSTRACT FROM AUTHOR]

The emopamil binding protein (EBP) is an important enzyme participating in the final steps of cholesterol biosynthesis in mammals. A predictive gene EBP-like , which encodes the protein with a high identity to human EBP, was found in chicken genome. No regulatory mechanisms and biological functions of EBP-like have been characterized in chickens. In the present study, the coding sequence of EBP-like was cloned, the phylogenetic trees of EBP/EBP-like were constructed and the genomic synteny of EBP-like was analyzed. The regulatory mechanism of EBP-like were explored with in vivo and in vitro experiments. The biological functions of EBP-like in liver cholesterol biosynthetic were examined by using gain- or loss-of-function strategies. The results showed that chicken EBP-like gene was originated from a common ancestral with Japanese quail EBP gene, and was relatively conservative with EBP gene among different species. The EBP-like gene was highly expressed in liver, its expression level was significantly increased in peak-laying stage, and was upregulated by estrogen. Inhibition of the EBP-like mRNA expression could restrain the expressions of EBP-like downstream genes (SC5D , DHCR24 , and DHCR7) in the cholesterol synthetic pathway, therefore downregulate the liver intracellular T-CHO level. In conclusion, as substitute of EBP gene in chickens, EBP-like plays a vital role in the process of chicken liver cholesterol synthesis. This research provides a basis for revealing the molecular regulatory mechanism of cholesterol synthesis in birds, contributes insights into the improvement of the growth and development, laying performance and egg quality in poultry. [ABSTRACT FROM AUTHOR]

Melting or thermal denaturation of a DNA molecule and the different bubble-rich, premelting DNA states that serve as a precursor for DNA thermal denaturation are vital events in DNA thermophysics. In this study, we employ cantilever-based sensing to firstly pinpoint the occurrence of DNA melting and identify the temperature Tm characterizing the melting. Very importantly, this sensing is carried out with an extremely small volume (∼picoliters) of DNA sample with the cantilever demonstrating an extremely high sensitivity on the order of mJ / g ⋅ K corresponding to pico-Joules of energy input. Secondly, this same large sensitivity of the cantilever is used to quantify the hitherto unknown thermophysical properties of the bubble-rich DNA premelting states. In fact, for both the melting and premelting states, the cantilever provides a framework to calculate the specific heat capacity and the storage and loss moduli of the cantilever-DNA-solution system, thereby establishing a platform for quantifying DNAs' thermo-mechanical behavior. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) play important roles in transcriptional and posttranscriptional regulation. However, the effects of lncRNAs on the meat quality of chicken hasn’t been elucidated clearly yet. Gushi chickens are popular in China because of their superior meat quality, particularly the tender flesh, and unique flavor. Gushi chickens are popular in China because of their superior meat quality, delicate flesh, and unique flavor. We performed RNA-Seq analysis of breast muscle from Gushi chicken at two physiological stages, including juvenile (G20W) and laying (G55W). In total, 186 lncRNAs and 881 mRNAs were differentially expressed between G20W and G55W (fold change ≥ 2.0, P < 0.05). Among them, 131 lncRNAs presented upregulated and 55 were downregulated. We identified the cis and trans target genes of the differentially expressed lncRNAs, and constructed lncRNA-mRNA interaction networks. The results showed that differentially expressed mRNAs and lncRNAs were mainly involved in ECM-receptor interaction, glycerophospholipid metabolism, ubiquitin-mediated proteolysis, and the biosynthesis of amino acids. In summary, our study utilized RNA-seq analysis to predict the functions of lncRNA on chicken meat quality. Furthermore, comprehensive analysis identified lncRNAs and their target genes, which may contribute to a better understanding of the molecular mechanisms underlying in poultry meat quality and provide a theoretical basis for further research. [ABSTRACT FROM AUTHOR]

Generating sufficient current density for powering electronic devices remains as one of the critical challenges of mechanical energy harvesting techniques based on piezo and triboelectricity, mainly due to the high impedance of the insulating material systems. Here we report on producing sustainable tunneling current using an unbiased, triboelectrically charged metal-insulator-semiconductor (MIS) point contact system, consisting of p-type silicon, silicon oxide and a metal tip. The native thin oxide (~ 1.6 nm) on the silicon surface provides a natural pathway for quantum mechanical tunneling of the triboelectrically generated electrons into the silicon substrate. Lateral back and forth sliding motion of the tip, irrespective of the direction of motion, generates a constant direct current (d.c.) with very high current density. The measured current shows an exponential decay with the thickness of oxide layer deposited with atomic layer deposition (ALD), confirming the quantum mechanical tunneling mechanism. It is proposed that the contact potential difference enhanced by triboelectric charging provides potential difference between metal point contact and the substrate. With single metallic micro probe sliding on a moderately doped p-type silicon, an open circuit voltage ( V oc ) of 300–400 mV and a short-circuit direct current ( I sc ) of 3–5 μA (a corresponding high current density, J , in the order of 1–10 A/m 2 ) have been observed. It is predicted from conductive-atomic force microscopy (C-AFM) experiment that the theoretical J can be as high as 10 4 A/m 2 . This new concept has the potential as a green energy harvesting technique where a broad range of material candidates and device configurations could be used. [ABSTRACT FROM AUTHOR]

Growth factor receptor-bound protein 2 (Grb2) have been proved by a lot of studies playing a major role in cell proliferation and cell differentiation. However, the regulation of Grb2 expression by microRNAs (miRNAs) in chicken breast muscle still remains unknown. The expression profile of Grb2 was checked based on our previous RNA sequencing data and the Grb2 relative expression level in breast muscle of aged hens (55-week-old) was validated significantly higher than juvenile hens (20-week-old) using qRT-PCR. miRNAs that interact with Grb2 have been predicted in chicken and the relationship between the potential miRNA and Grb2 was verified using dual luciferase reporter assay in chicken DF1 cells. Dual-luciferase reporter assays results demonstrated that the expression of luciferase reporter gene linked with part sequence of the 3′UTR of chicken Grb2 gene was down-regulated by the overexpression of gga (Gallus Gallus)-miR-200a-3p in the DF1 cells, and the down-regulation behavior was abolished when the gga-miR-200a-3p binding site in 3′UTR of Grb2 was mutated, indicating that gga-miR-200a can suppress the expression level of its target gene Grb2. Therefore, we concluded that the significantly increased expression level of Grb2 in the breast muscle of aged chicken can (at least partly can) be explained by the decreased expression of miR-200a, which reduced the inhibitory effect on Grb2. Taken together, these findings suggest that gga-miR-200a can suppress the expression level of its target gene Grb2 and might be involved in the cell differentiation and proliferation of chicken breast muscle through binding with the 3’UTR of Grb2. [ABSTRACT FROM AUTHOR]

Spontaneous self-assemblies of biomolecules can generate geometrical patterns. Our findings provide an insight into the mechanism of self-assembled ring pattern generation by human serum albumin (HSA). The self-assembly is a process guided by kinetic and thermodynamic parameters. The generated protein ring patterns display a behavior which is geometrically related to a n-simplex model and is explained through thermodynamics and chemical kinetics. [ABSTRACT FROM AUTHOR]

Carbonized cellulose nanofibrils (CNF) have been employed to improve the rate performance of activated carbon (AC) traditionally used in supercapacitors. Because of the large amount of surface functionalities, CNF form strongly interconnected composite with AC, which turns into a free-standing carbon nanofibers/AC film after carbonization. In the film, the carbon nanofibers are ‘welded’ on AC particles and integrate them into one piece of carbon. The interaction between AC and carbon nanofibers, originating from the strong AC-nanocellulose affinity, is much stronger than the traditional physically mixed AC/nanocarbon composite and also significantly reduces the contact resistance in the composite. Conductive atomic force microscope (C-AFM) analysis reveals that the network of carbonized CNF possesses markedly better electron transport efficiency than the AC particles. When tested as supercapacitor electrode at commercial level mass loading, the composite film exhibits 2 times slower capacitance fading at high current and 3 times higher maximum power density than the bare AC. In addition, using the nanocellulose, which is derived from renewable resources, increases the total electrode cost only by a small margin, thereby making the composite a competitive electrode material for electricity storage on a large scale. [ABSTRACT FROM AUTHOR]

We report a simple, rapid and cost effective detection technique for Escherichia coli ( E. coli ) using a Light Addressable Potentiometric Sensor integrated with electrospun poly acrylic acid/polyvinyl alcohol (PAA/PVA) hydrogel nanofibers as a sensing layer (NF-LAPS). Changes in pH of the media are detected as E. coli cells ferment sugar molecules and increase acidity of the surrounding. A super-Nernstian response of a 74 mV/pH change in the NF-LAPS provides high sensitivity towards E. coli with a theoretical limit of detection (LOD) of 20 CFU/ml. The high sensitivity is associated with the pH sensitive behavior of the NFs on the surface. Detection of acidic species released in cellular metabolism of pathogens in the presence of carbon source renders the sensing mechanism cheaper, less time consuming and more practical than the antibody-antigen interaction based approach. Selectivity towards E. coli for applications in drinking water detection is ensured by the incorporation of d -mannose for specific binding. [ABSTRACT FROM AUTHOR]

Ligand-directed targeting and capturing of cancer cells is a new approach for detecting circulating tumor cells (CTCs). Ligands such as antibodies have been successfully used for capturing cancer cells and an antibody based system (CellSearch®) is currently used clinically to enumerate CTCs. Here we report the use of a peptide moiety in conjunction with a microcantilever array system to selectively detect CTCs resulting from cancer, specifically breast cancer. A sensing microcantilever, functionalized with a breast cancer specific peptide 18-4 (WxEAAYQrFL), showed significant deflection on cancer cell (MCF7 and MDA-MB-231) binding compared to when exposed to noncancerous (MCF10A and HUVEC) cells. The peptide-functionalized microcantilever allowed efficient capture and detection of cancer cells in MCF7 spiked human blood samples emulating CTCs in human blood. A detection limit of 50-100 cancer cells mL-1 from blood samples was achieved with a capture yield of 80% from spiked whole blood samples. The results emphasize the potential of peptide 18-4 as a novel peptide for capturing and detecting cancer cells in conjunction with nanomechanical cantilever platform. The reported peptide-based cantilever platform represents a new analytical approach that can lead to an alternative to the various detection platforms and can be leveraged to further study CTCs. [ABSTRACT FROM AUTHOR]

Broad-spectrum biosensing technologiesexamine sensor signals usingbiomarkers, such as proteins, DNA, antibodies, specific cells, andmacromolecules, based on direct- or indirect-conformational changes.Here, we have investigated the pH-dependent conformational isomerizationof human serum albumin (HSA) using microcantilevers as a sensing platform.Native and denatured proteins were immobilized on cantilever surfacesto understand the effect of pH on conformational changes of the proteinwith respect to the coupling ligand. Our results show that protonationand deprotonation of amino acid residues on proteins play a significantrole in generating charge-induced cantilever deflection. Surface plasmonresonance (SPR) was employed as a complementary technique to validatethe results. [ABSTRACT FROM AUTHOR]

Real-time, label-free detection of Gram-positive bacteria with high selectivity and sensitivity is demonstrated using an interdigitated impedimetric array functionalized with naturally produced antimicrobial peptide from class IIa bacteriocins. The antimicrobial peptide, leucocin A, was chemically synthesized and covalently immobilized on interdigitated gold microelectrodes via the interaction between the C-terminal carboxylic acid of the peptide and free amines of a preattached thiolated linker. Exposing the peptide sensor to various concentrations of Gram-positive bacteria generated reproducible impedance spectra that detected peptide–bacteria interactions at a concentration of 1 cell/μL. The peptide sensor also selectively detected Listeria monocytogenes from other Gram-positive strains at a concentration of 103 cfu mL–1. The study highlights that short peptide ligands from bacteriocin class offer high selectivity in bacterial detection and can be used in developing a robust, portable biosensor device to efficiently detect pathogenic Gram-positive bacteria in food samples. [ABSTRACT FROM AUTHOR]

Egg-laying performance is one of the most important economic traits in the poultry industry. Commercial layers can lay one egg almost every day during their peak-laying period. However, many Chinese indigenous chicken breeds show a relatively low egg-laying rate, even during their peak-laying period. To understand what makes the difference in egg production, we compared the hypothalamus transcriptome profiles of Lushi blue-shelled-egg chickens (LBS), a Chinese indigenous breed with low egg-laying rate and Rhode Island Red chickens (RIR), a commercial layer with relatively high egg-laying rate using RNA-seq. A total of 753 differentially expressed genes (DEGs) were obtained. Of these DEGs, 38 genes were enriched in 2 Gene Ontology (GO) terms, namely reproduction term and the reproductive process term, and 6 KEGG pathways, namely Wnt signaling pathway, Oocyte meiosis, GnRH signaling pathway, Thyroid hormone signaling pathway, Thyroid hormone synthesis and MAPK signaling pathway, which have been long known to be involved in egg production regulation. To further determine the core genes from the 38 DEGs, protein-protein interaction (PPI) network, co-expression network and transcriptional regulatory network analyses were carried out. After integrated analysis and experimental validation, 4 core genes including RAC1, MRE11A, MAP7 and SOX5 were identified as the potential core genes that are responsible for the laying-rate difference between the 2 breeds. These findings paved the way for future investigating the mechanism of egg-laying regulation and enriched the chicken reproductive regulation theory. [ABSTRACT FROM AUTHOR]

Although tip‐enhanced tribo‐tunneling in metal/semiconductor point nanocontact is capable of producing DC with high current density, scaling up the process for power harvesting for practical applications is challenging due to the complexity of tip array fabrication and insufficient voltage output. Here, it is demonstrated that mechanical contact between a carbon aerogel and silicon (SiO2/Si) interface naturally forms multiple nanocontacts for tribo‐tunneling current generation with an open‐circuit voltage output (VOC) reaching 2 V, and short‐circuit DC current output (ISC) of ≈15 µA. It has a theoretical current density ( J*) on the order of 100 A m−2. Molecular dynamics simulation and atomistic field theory show that a strong localized electronic excitation can be induced at a dynamic carbon/SiO2 sliding interface, which is in good agreement with the experimental results. The DC power output is enhanced by the intense local pressure at the presence of nanocontacts, as well as the increased sliding velocity v. To demonstrate the method for practical applications, light‐emitting diodes (LEDs) with different colors are successfully lighted by a single‐carbon aerogel monolith/SiO2 sliding unit, and the DC electricity is stored in a capacitor without an additional rectification circuit. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen (N2) reduction reaction (NRR) presents a sustainable alternative to the Haber–Bosch process for ammonia (NH3) synthesis. Iron phthalocyanine (FePc) is demonstrated as a promising catalyst for the electrocatalytic NRR. However, FePc with planar symmetric Fe‐N4 sites exhibits poor N2 adsorption and activation capabilities, resulting in an unsatisfactory NRR performance. Herein, an axial oxygen coordination strategy is developed to optimize the local electron distribution on FePc for improving N2 adsorption and activation. The as‐obtained FePc‐O‐CP shows a superior NH3 yield rate (59.72 µg h−1 mg−1cat.) and a considerable Faradaic efficiency (13.76%) in 0.1 m HCl. Density functional theory (DFT) calculations verify that the axial oxygen ligand on FePc inhibits the adsorption of H+ and enhances the N2 adsorption and activation, thereby greatly promoting NH3 generation. This work reveals the significance of regulating the local coordination environment of single‐atom catalysts for improving electrocatalytic NRR performance and provides a feasible strategy for the rational design of atomic‐scale active sites. [ABSTRACT FROM AUTHOR]

The elongation of very long chain fatty acids protein 6 (ELOVL6) encodes a fatty acid elongase that is responsible for the final step in endogenous saturated fatty acid synthesis and involves in de novo lipogenesis. Though the regulatory mechanism of ELOVL6 expression has been studied extensively, little is known about the role of miRNA in regulating ELOVL6 gene expression in chicken until now. To investigate the regulatory mechanism of miRNA on the expression of ELOVL6 gene, bioinformatics analysis was employed to predict the potential miRNAs that binding with the 3′untranslated region (3′UTR) of ELOVL6. The putative miRNA was further screened by comparative analysis with previous miRNA-seq results. Gga-miR-22-3p, which could bind with the 3′UTR of ELOVL6 and showed negative expression correlation with ELOVL6 gene in chicken liver, was obtained. Tissue expression profiles showed that gga-miR-22-3p and ELOVL6 are extensively expressed in many tissues, and ELOVL6 with high expression level in kidney and liver tissues, and gga-miR-22-3p with high expression in lung and heart. Dual-luciferase reporter assays results indicated that the expression of luciferase reporter gene linked with part sequence of the 3′UTR of chicken ELOVL6 gene was down-regulated by the overexpression of gga-miR-22-3p in the DF1 cells, and the down-regulation behavior was abolished when the gga-miR-22-3p binding site in 3′UTR of ELOVL6 was mutated ( P > 0.05). Furthermore, the ELOVL6 expression in chicken hepatocytes was down-regulated when miR-22-3p was over-expressed. Therefore, we concluded that miR-22-3p might involve in controlling the hepatic lipid composition through affecting the expression of ELOVL6 gene, and could serve as a regulator of lipid metabolism in the liver of egg-laying hen. [ABSTRACT FROM AUTHOR]

• Chicken ACSL2 was evolutionally lost. • Chicken ACSLs were evolutionally clustered into ACSL1/5/6 and ACSL3/4. • Decreased ACSL1 and increased ACSL5 expression levels were detected in the liver of peak- versus pre-laying hens. • Estrogen could transcriptionally inhibit ACSL1/3/4 and activate ACSL6. Long chain acyl-CoA synthetases (ACSLs), which drive the conversion of long chain fatty acid into acyl-CoA, an ingredient of lipid synthesis, have been well-acknowledged to exert an indispensable role in many metabolic processes in mammals, especially lipid metabolism. However, in chicken, the evolutionary characteristics, expression profiles and regulatory mechanisms of ACSL gene family are rarely understood. Here, we analyzed the genomic synteny, gene structure, evolutionary event and functional domains of the ACSL gene family members using bioinformatics methods. The spatiotemporal expression profiles of ACSL gene family, and their regulatory mechanism were investigated via bioinformatics analysis incorporated with in vivo and in vitro estrogen-treated experiments. Our results indicated that ACSL2 gene was indeed evolutionarily lost in the genome of chicken. Chicken ACSLs shared an AMP-binding functional domain, as well as highly conversed ATP/AMP and FACS signature motifs, and were clustered into two clades, ACSL1/5/6 and ACSL3/4, based on high sequence similarity, similar gene features and conversed motifs. Chicken ACSLs showed differential tissue expression distributions, wherein the significantly decreased expression level of ACSL1 and the significantly increased expression level of ACSL5 were found, respectively, the expression levels of the other ACSL members remained unchanged in the liver of peak-laying hens versus pre-laying hens. Moreover, the transcription activity of ACSL1 , ACSL3 and ACSL4 was silenced and ACSL6 was activated by estrogen, but no response to ACSL5. In conclusion, though having highly conversed functional domains, chicken ACSL gene family is organized into two separate groups, ACSL1/5/6 and ACSL3/4 , and exhibits varying expression profiles and estrogen effects. These results not only pave the way for better understanding the specific functions of ACSL genes in avian lipid metabolism, but also provide a valuable evidence for gene family characteristics. [ABSTRACT FROM AUTHOR]