Imprinting at the KBTBD6 locus involves species-specific m ternal methylation and monoallelic expression in livestock animals

Background The primary differentially methylated regions(DMRs) which are maternally hypermethylated serve as imprinting control regions(ICRs) that drive monoallelic gene expression, and these ICRs have been investigated due to their implications in mammalian development. Although a subset of genes has been identified as imprinted, in-depth comparative approach needs to be developed for identification of species-specific imprinted genes. Here, we examined DNA methylation status and allelic expression at the KBTBD6 locus across species and tissues and explored potential mechanisms of imprinting.Results Using whole-genome bisulfite sequencing and RNA-sequencing on parthenogenetic and normal porcine embryos, we identified a maternally hypermethylated DMR between the embryos at the KBTBD6 promoter Cp G island and paternal monoallelic expression of KBTBD6. Also, in analyzed domesticated mammals but not in humans, non-human primates and mice, the KBTBD6 promoter Cp G islands were methylated in oocytes and/or allelically methyl-ated in tissues, and monoallelic KBTBD6 expression was observed, indicating livestock-specific imprinting. Further analysis revealed that these Cp G islands were embedded within transcripts in porcine and bovine oocytes which coexisted with an active transcription mark and DNA methylation, implying the presence of transcription-dependent imprinting.Conclusions In this study, our comparative approach revealed an imprinted expression of the KBTBD6 gene in domesticated mammals, but not in humans, non-human primates, and mice which implicates species-specific evolution of genomic imprinting.

Ionically Imprinting-Based Copper(Ⅱ)Label-Free Detection for Preventing Hearing Loss

Copper is a microelement with important physiological functions in the body.However,the excess copper ion(Cu^(2+))may cause severe health problems,such as hair cell apoptosis and the resultant hearing loss.Therefore,the assay of Cu^(2+)is important.We integrate ionic imprinting technology(IIT)and structurally colored hydrogel beads to prepare chitosan-based ionically imprinted hydrogel beads(IIHBs)as a low-cost and high-specificity platform for Cu^(2+)detection.The IIHBs have a macroporous microstructure,uniform size,vivid structural color,and magnetic responsiveness.When incubated in solution,IIHBs recognize Cu^(2+)and exhibit a reflective peak change,thereby achieving label-free detection.In addition,benefiting from the IIT,the IIHBs display good specificity and selectivity and have an imprinting factor of 19.14 at 100μmol·L^(-1).These features indicated that the developed IIHBs are promising candidates for Cu^(2+)detection,particularly for the prevention of hearing loss.

Explicit K-symplectic methods for nonseparable non-canonical Hamiltonian systems

We propose efficient numerical methods for nonseparable non-canonical Hamiltonian systems which are explicit,K-symplectic in the extended phase space with long time energy conservation properties. They are based on extending the original phase space to several copies of the phase space and imposing a mechanical restraint on the copies of the phase space. Explicit K-symplectic methods are constructed for two non-canonical Hamiltonian systems. Numerical tests show that the proposed methods exhibit good numerical performance in preserving the phase orbit and the energy of the system over long time, whereas higher order Runge–Kutta methods do not preserve these properties. Numerical tests also show that the K-symplectic methods exhibit better efficiency than that of the same order implicit symplectic, explicit and implicit symplectic methods for the original nonseparable non-canonical systems. On the other hand, the fourth order K-symplectic method is more efficient than the fourth order Yoshida’s method, the optimized partitioned Runge–Kutta and Runge–Kutta–Nystr ¨om explicit K-symplectic methods for the extended phase space Hamiltonians, but less efficient than the the optimized partitioned Runge–Kutta and Runge–Kutta–Nystr ¨om extended phase space symplectic-like methods with the midpoint permutation.

On the relationship between imprint and reliability in Hf_(0.5)Zr_(0.5)O_(2) based ferroelectric random access memory

The detrimental effect of imprint,which can cause misreading problem,has hindered the application of ferroelectric HfO_(2).In this work,we present results of a comprehensive reliability evaluation of Hf_(0.5)Zr_(0.5)O_(2)-based ferroelectric random access memory.The influence of imprint on the retention and endurance is demonstrated.Furthermore,a solution in circuity is pro-posed to effectively solve the misreading problem caused by imprint.

MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation

In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 microns.Achieving such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously developed.To mitigate data races when calculating internal forces,intermediate arrays are introduced within the OpenMP directive.This helps ensure proper synchronization and avoid conflicts during parallel execution.Additionally,in the MPI implementation,the coins are partitioned into the desired number of regions.This division allows for efficient distribution of computational tasks across multiple processes.Numerical simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel efficiency.The results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental observations.Additionally,speedup ratio and parallel efficiency are assessed for the coining process simulation.The pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/OpenMP programming model.This approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns.

Maternal imprinting of the neonatal microbiota colonization in intrauterine growth restricted piglets:a review

Early colonization of intestinal microbiota during the neonatal stage plays an important role on the development of intestinal immune system and nutrients absorption of the host.Compared to the normal birth weight(NBW)piglets,intrauterine growth restricted(IUGR)piglets have a different intestinal microbiota during their early life,which is related to maternal imprinting on intestinal microbial succession during gestation,at birth and via suckling.Imbalanced allocation of limited nutrients among fetuses during gestation could be one of the main causes for impaired intestinal development and microbiota colonization in neonatal IUGR piglets.In this review,we summarized the potential impact of maternal imprinting on the colonization of the intestinal microbiota in IUGR piglets,including maternal undernutrition,imbalanced allocation of nutrients among fetuses,as well as vertical microbial transmission from mother to offspring during gestation and lactation.At the same time,we give information about the current maternal nutritional strategies(mainly breastfeeding,probiotics and prebiotics)to help colonization of the advantageous intestinal microbiota for IUGR piglets.

Characterization of the imprinting and expression patterns of ZAG2 in maize endosperm and embryo

ZAG2 has been identified as a maternally expressed imprinted gene in maize endosperm.Our study revealed that paternally inherited ZAG2 alleles were imprinted in maize endosperm and embryo at 14 days after pollination(DAP), and consistently imprinted in endosperm at 10, 12, 16, 18, 20, 22, 24, 26, and 28 DAP in reciprocal crosses between B73 and Mo17. ZAG2 alleles were also imprinted in reciprocal crosses between Zheng 58 and Chang7-2 and between Huang C and 178. ZAG2 alleles exhibited differential imprinting in hybrids of 178 × Huang C and B73 × Mo17, while in other hybrids ZAG2 alleles exhibited binary imprinting. The tissue-specific expression pattern of ZAG2 showed that ZAG2 was expressed at a high level in immature ears, suggesting that ZAG2 plays important roles in not only kernel but ear development.

Genome-wide identification of imprinted genes in pigs and their different imprinting status compared with other mammals

DEAR EDITOR,Genomic imprinting often results in parent-of-origin specific differential expression of maternally and paternally inherited alleles and plays an essential role in mammalian development and growth.Mammalian genomic imprinting has primarily been studied in mice and humans,with only limited information available for pigs.To systematically characterize this phenomenon and evaluate imprinting status between different species,we investigated imprinted genes on a genome-wide scale in pig brain tissues.

Enantiomeric Resolution on L-Carnitine Selective Polymers Prepared by Molecular Imprinting

L-carnitine selective polymers were prepared by molecular imprinting using methacrylic acid as the functional monomer. The acid function of the monomer is expected to form hydrogen bond and ionic interactions with the amine function of the target molecule L-carnitine. The imprinted polymers were used as stationary phases in high-performance liquid chromatography (HPLC). It was shown that L-carnitine imprinted polymer exhibited a higher affinity to its template molecule, while the non-imprinted polymer had no affinity to the compounds tested. Racemic carnitine hydrochloride was efficiently resolved on the L-carnitine imprinted polymer, and the separation factor is 1.9.

Imprinting Analysis of RTL1 and DIO3 Genes and Their Association with Carcass Traits in Pigs (Sus scrofa)

Imprinted genes play significant roles in the regulation of fetal growth, development, function of the placenta and postnatal behavior in mammals, but little is known in pigs. In order to investigate the imprinting status of porcine retro-transposon like 1 （RTL1） and type 3 iodothyronine deiodinase （DIO3） genes, DNA or RNA samples of the parents and F1 animals, generated with reciprocal crosses between Large White and Meishan breeds, were isolated, and analyzed by reverse transcription polymerase chain reaction restriction fragment length polymorphism （RT-PCR-RFLP）. The results demonstrated that the RTL1 gene was paternally expressed in 10 tissues, such as the skeletal muscle, heart, spleen, liver, kidney, lung, stomach, fat, small intestine and brain, and D103 gene exhibited paternal expression in the skeletal muscle, heart, spleen, lung, stomach, and brain, in 2-month-old pigs. The association of RTL1 and DI03 with carcass traits was further analyzed in the F2 population of Large White×Meishan pigs. The statistical results showed that the R TL1 A1101G polymorphism （EU781029） was significantly associated with lean meat percentage （LMP） and fat meat percentage （FMP） （P〈0.05）, while the D103 A744C polymorphism （AY533208） was not significantly associated with any carcass traits. These results indicate that the imprinting status of RTL1 and DIO3 is well kept across the mammalian species, and porcine RTL1 may have important roles in muscle growth and fat deposition.

Making High Selective Molecule Imprinting Polymer (MIP) In Polar Solvent

Acrylamide was used as functional monomer to make high chiral selective molecule imprinting polymers against N-alpha-protected amino acid in polar solvent. The factor, which influence the efficiency of the polymer and the mechanism of chiral recognition were investigated.

Characterization,Imprinting Status and Tissue Distribution of Porcine GTL2 Gene

The callipyge （CLPG） phenotype, exhibiting polar overdominance （POD）, is an inherited skeletal muscle hypertrophy described in sheep. The callipyge locus maps to the distal portion of ovine chromosome 18 within the DLKI-GTL2 region and corresponds to human chromosome 14 and mouse chromosome 12. The POD phenomenon is confirmed to the homologous region of swine chromosome 7. In order to clone and investigate the expression of porcine GTL2 gene, DNA and RNA samples from 60-day-old F1 animals, generated with reciprocal crosses between Large White and Meishan breeds and their parents, were used. The authors showed that porcine GTL2 acted as a uoncoding RNA. cDNA samples exhibited maternal expression of the gene in the heart, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, and fat in pigs, and a unique tissue-specific expression different from that of humans and mice. These results indicated that the gene was conserved in the pig, human, mouse, and bovine. It will be of interest to further study the gene functions in muscle growth and fat deposition.

Molecular Imprinting Fibrous Membranes of Poly(acrylonitrile-co-acrylic acid) Prepared by Electrospinning

IntroductionOver the past few decades, molecular imprinting has been described as a technology for preparing ＂molecular doors＂ which can be matched to ＂template keys＂. It has been found to be a simple and effective approach to introduce specific recognition sites into synthetic polymers, namely, to create molecular imprinting polymers Remarkable features such as stability, ease of preparation and low cost, have made molecular imprinting polymers particularly attractive in chemical sensors, catalysis, drug delivery, and dedicated separations. Practical applications of molecular imprinting polymers require accessible sites, fast mass transfer, and quick binding. However, present techniques used to prepare molecular imprinting polymers most often result in materials exhibiting a high affinity and selectivity but a low capacity and poor site accessibility for the target molecules. It is also very difficult to remove the imprinted molecules located in these molecular imprinting polymers because the highly cross-linked structures do not allow the templates to move freely. To some extent, combining molecular imprinting technology with membrane separation and surface imprinting can overcome the shortcomings, such as mass transfer limitations and non-quantitative recovery of the template molecules seen for imprinted materials fabricated by conventional bulk methods. In that ease, it appears to us that molecular imprinting polymers with high surface area to volume ratios are particularly desirable for largescale applications. Eleetrospun nano and ultrafine fibrous membranes are the most suitable materials due to advantages such as： （1） large specific surfaces, providing relatively high imprinting sites per unit mass; （2） fine porous structures, resulting in the accessibility of imprinting sites and low diffusion resistance necessary for high efficiency; and （3） easy recoverability from practical operation or applicability for continuous usages. Therefore, in this work, we prepared a unique kind of imprinted material--molecularly imprinted fibrous membranes of poly （ acrylonitrile-co-acrylic acid） fabricated by means of an electrospinning process.

Different Imprinting Status of IGF-2 in Epithelial Ov arian Tumors

To explore whether the imprinting status of IGF 2 in the malignant epithelial ovarian tumors is different from that in benign tumors, the target sequences (DNA and RNA) which contain a polymorphism site for ApaI restriction endonuclease digestion were amplified with PCR and RT PCR methods. Then the PCR/RT PCR products were digested by ApaI. The IGF 2 transcriptional pattern came out from the results of endonucleases digestion. Among the 36 cases of benign epithelial ovarian tumors, 20 were heterozygous for ApaI locus and all showed genomic imprinting. While in the malignant group, 22 were heterozygous for ApaI locus but six were found to lose imprinting. Significant differences existed between the two groups ( P <0.05). Loss of imprinting of IGF 2 may serve as a marker for differentiating the malignant ovarian cancers from the benign ones. In a new field of molecular genetics, our research provides an experimental basis for genetic diagnosis and treatment of the ovarian cancers.

Computer Simulation and Experimental Investigations of Phenobarbital Molecular Imprinting System

The interaction process between the phenobarbital（PHN） and acrylamide（AM） was studied using the M062X/6-31G（d,p） method. The PHN and AM were used as the template and functional monomer,respectively. The molecular electrostatic potential（MEP） was simulated for predicting the reactive sites. The atoms in molecules theory helped to reveal the imprinting mechanism and optimize the molar ratios for PHN and AM. The molecular imprinted polymers（MIPs） containing PHN were synthesized through the precipitation polymerization. The diameter range of the obtained MIPs was from 150 to 390 nm. According to the computational results,MIPs with the molar ratio of PHN and AM equal to 1：6 showed high selective adsorption for PHN. The apparent maximum adsorption quantity（Q_（max）） of MIPs toward PHN was 7.9 mg/g,and the Qmax of nonimprinted polymer microspheres（NIPs） was 3.2 mg/g. Herein,the studies can provide theoretical and experimental references for the controllable fabrication of MIPs.

Molecular Imprinting of (R)-(+)-α-Methylbenzylamine for Chiral Stationary Phase

A new type of molecular imprinting stationary phase was prepared by using R- (+)-α -methylbenzy lamine as the print molecule. Experiments of high performance liquid chromatography show that the new stationary phase has high enantio-selectivity and discriminates (R, S) -(± )- α -methylbenzylamine successful ly with α value of 1. 67

Imprinting, methylation, and expression characterization of the maize ETHYLENE-INSENSITIVE 2-like gene

The endosperm plays essential roles in embryogenesis and seed germination and provides abundant resources for human food and industrial products. Identification of genes regulating the development of the endosperm and elucidation of their functions is of great importance for maize genetics and breeding. This study showed that the genespecific imprinted gene, ETHYLENE-INSENSITIVE 2-like(EIN2-like), is maternally expressed in both endosperm and embryo. The maternally expressed pattern was maintained throughout later seed developmental stages. Bisulfite sequencing using DNA obtained from hybrid endosperm tissues showed that the upstream regions of the alleles of EIN2-like were highly methylated at symmetrical sites(CG and CHG). A differentially methylated region in the upstream part of the maternal allele of EIN2-like was identified and found to be hypomethylated. Expression analysis showed that EIN2-like was highly expressed in the maize endosperm as well as at different stages of cell differentiation(8–12 days after pollination) in the hybrid endosperm. These results suggest that the maternally expressed gene EIN2-like may play crucial roles in the regulation of seed development.

Simulation and Preparation of Molecular Imprinting System with Atrazine as Template

In this work, atrazine functions as a template molecule, and trifluoromethacrylic acid （TFMAA）, methacrylic acid （MAA）, methyl methacrylate （MMA）, and acrylamide （AM） serve as functional monomers, respectively. By using density functional theory （DFT）, the computational approach was carried out to simulate the self-assembly system of template and functional monomer. The geometry optimization, action sites, binding energies, and molecular imprinting mechanism of complexes with different functional monomers in different proportions were predicted. The simulation results showed that atrazine and the functional monomers interacted through hydrogen bond. Among the 4 functional monomers, the imprinted complex formed by TFMAA and atrazine with a ratio of （1：6） has the lowest binding energy and the best imprinting effect. Then, the microspheres of molecularly imprinted polymer （MIPs） were prepared by precipitating polymerization using atrazine as the template molecule and TFMAA as the functional monomer. The microspheres were observed by scanning electron microscopy （SEM）. The results showed that atrazine MIP microspheres had average particle size of 400 nm, which was greater than the non-imprinted polymeric microspheres （NIPs）. Dynamic adsorption experiments of MIPs showed that the adsorption reaction reached balance after 200 min. Analysis of the Scatchard plot revealed that the binding sites of MIPs to atrazine were equal class under the studied concentration range. The dissociation constant （Kd） and apparent maximum adsorption quantity （Qmax） of MIPs were 3.6×10^-5 mol/L and 4.83μmol/g, respectively. The study of selective adsorption between atrazine and metribuzin showed that imprinted microspheres had high selectivity for the template molecule atrazine.

Simultaneous Chiral Separation Using a Combinatorial Molecular Imprinting Phase

Molecular imprinting chiral stationary phase against Cbz-L-Serine (Cbz-L-Ser) and Cbz-L-Alaine (Cbz-L-Ala) were prepared utilizing acrylamide + 2-vinylpyridine as combined basic functional monomers. Cross-selectivity was used to obtain simultaneous chiral separations of Cbz-DL-Ser and Cbz-DL-Ala by connecting two columns packed with Cbz-L-Ser and Cbz-L-Ala imprinted chiral stationary phase, respectively.

Polyacrylamide hydrogels with phenylboronic acid moieties for the imprinting of proteins

在这封信， N-acryloyl-3-aminophenylboronic 酸(AAPBA ) 为蛋白质印作为新功能的单体被综合然后检验。与 acrylamide 被异分子聚合生产印血红素或印溶解酵素的 hydrogels 被允许。在重捆测试的模板，印的胶化随 prepolymerization 配方的 AAPBA 数量的增加在特定的绑定显示出重要增加。这些结果显示 AAPBA 可以是为它和蛋白质分子的中等相互作用的有用功能的单体。