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Precision agriculture, and more specifically Site-Specific Crop Management (SSCM), has been implemented in some form across nearly all agricultural production systems over the past 25 years. Adoption has been greatest in developed agricultural countries. In this review article, the current situation of SSCM adoption and application is investigated from the perspective of a developed (UK) and developing (China) agricultural economy. The current state-of-the art is reviewed with an emphasis on developments in position system technology and satellite-based remote sensing. This is augmented with observations on the differences between the use of SSCM technologies and methodologies in the UK and China and discussion of the opportunities for (and limitations to) increasing SSCM adoption in developing agricultural economies. A particular emphasis is given to the role of socio-demographic factors and the application of responsible research and innovation (RRI) in translating agri-technologies into China and other developing agricultural economies. Several key research and development areas are identified that need to be addressed to facilitate the delivery of SSCM as a holistic service into areas with low precision agriculture (PA) adoption. This has implications for developed as well as developing agricultural economies.

Simple Summary: Traditional musk is a scarce resource of traditional Chinese medicine in China, which is difficult to obtain. Few studies have been reported on the search for alternatives to musk. To this end, we collected muskrat musk, which is widely regarded as a substitute for musk, and performed Gas Chromatography Time-of-Flight Mass Spectrometry (GC–TOF–MS) metabolomics analysis together with musk. The results showed that muskrat musk and musk had certain similarities in terms of their composition, but the important active components of muscone were missing. Analysis of muskrat musk at different ages showed that amino acids, fatty acids, and steroids were significantly enriched, which may affect the function of muskrat scent glands through local enrichment for a short time. Muskrat musk is considered to be a potential substitute for traditional musk. However, little is known about the similarity between muskrat musk and musk, and whether it is related to muskrat age. In this study, muskrat musk (MR1, MR2, and MR3) were from 1, 2, and 3-year-old muskrats, respectively, and white musk (WM) and brown musk (BM) were picked from male forest musk deer. The results indicated that muskrat musk had higher similarity to WM than BM. Further research showed that RM3 had the highest matched degree with WM. By significantly different metabolite analysis, we found that 52 metabolites continue to increase from 1- to 3-year-old muskrats. In total, 7 and 15 metabolites were significantly decreased in RM1 vs. RM2 and RM2 vs. RM3, respectively. Meanwhile, 30 and 17 signaling pathways were observed from increased and decreased metabolites, respectively. The increased metabolites mainly entailed enrichment in amino acid biosynthesis and metabolism, steroid hormone biosynthesis, and fatty acid biosynthesis. In conclusion, muskrat musk from three-year-old muskrat is a relatively good substitute for white musk, and the result also implies that these biological processes of amino acid biosynthesis and metabolism, steroid hormone biosynthesis, and fatty acid biosynthesis are beneficial to the secretion of muskrat musk. [ABSTRACT FROM AUTHOR]

Objectives: Mesoderm, derived from a new layer between epiblast and hypoblast during gastrulation, can differentiate into various tissues, including muscles, bones, kidneys, blood, and the urogenital system. However, systematic elucidation of mesoderm characteristics and specific markers remains a challenge. This study aims to screen and identify candidate genes important for mesoderm development. Materials and Methods: Cells originating from the three germ layers were obtained by laser capture microdissection, followed by microcellular RNA sequencing. Mesoderm‐specific differentially expressed genes (DEGs) were identified by using a combination of three bioinformatics pipelines. Candidate mesoderm‐specific genes expression were verified by real‐time quantitative polymerase chain reaction analysis and immunohistochemistry. Functional analyses were verified by ESCs‐EBs differentiation and colony‐forming units (CFUs) assay. Results: A total of 1962 differentially expressed mesoderm genes were found, out of which 50 were candidate mesoderm‐specific DEGs which mainly participate in somite development, formation of the primary germ layer, segmentation, mesoderm development, and pattern specification process by GO analysis. Representative genes Cdh2, Cdh11, Jag1, T, Fn‐1, and Pcdh7 were specifically expressed in mesoderm among the three germ layers. Pcdh7 as membrane‐associated gene has hematopoietic‐relevant functions identified by ESCs‐EBs differentiation and CFUs assay. Conclusions: Spatial transcriptomic profiling with multi‐method analysis and confirmation revealed candidate mesoderm progenitors. This approach appears to be efficient and reliable and can be extended to screen and validate candidate genes in various cellular systems. [ABSTRACT FROM AUTHOR]

RING finger protein 135 has an important role in the occurrence of many cancers; however its regulation and function of RNF135 in hepatocellular carcinoma remains unknown. The promoter methylation status and mRNA expression of RNF135 was evaluated by methylation-specific PCR, semi-quantitative RT-PCR, and real-time quantitative PCR in HCC tissues and cell lines, and further analyzed from The Cancer Genome Atlas database. Wound healing assay, transwell migration, cell viability, and colony formation assay were performed to investigate the function of RNF135. GSEA analysis, TIMER database, and ESTIMATE algorithm were used to decipher the associated pathway and immune infiltration. The survival analysis was applied to assess the prognostic value of RNF135. RNF135 expression was downregulated in HCC tissues and 5 of 8 HCC cell lines, and was negatively correlated with its promoter hypermethylation. Demethylating regent decitabine restored RNF135 expression on the cellular level. Knockdown of RNF135 expression enhanced the migration of HCC cells, while RNF135 overexpression and decitabine treatment repressed cell migration. Bioinformatics analysis and immunohistochemistry revealed a positive relationship between RNF135 expression and six immune cell infiltrates (B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells). Survival analysis disclosed that RNF135 hypermethylation is independently associated with poor clinical outcomes in HCC. Decreased RNF135 expression driven by promoter hypermethylation frequently occurred in HCC and associated with prognosis of HCC. RNF135 functions as a tumor suppressor and is involved in tumor immune microenvironment in HCC. [ABSTRACT FROM AUTHOR]

Animal gut microbiota begins to colonize after birth and is functionally indispensable for maintaining the health of the host. It has been reported that gender and age influence the composition of the intestinal microbiome. However, the effects of gender and age on the intestinal microorganism of forest musk deer (FMD) remain unclear. The aim of this study was to establish the relationship between the structure and composition of fecal microbiota of male and female forest musk deer with age. Here, Illumina Miseq 300PE sequencing platform targeting 16S rRNA V3–V4 hypervariable region applied to define the fecal microbiota of male and female FMD with two age groups, juvenile (age 1–2 years) and adult (age 4–10 years). Alpha diversity index did not show significant difference in bacterial diversity between the males and females or among age groups. The intestinal microbiota of FMD was dominated by three phyla, the Firmicutes, Proteobacteria and Bacteroidetes regardless of gender and different ages. Higher proportions of Proteobacteria were found in adult male and juvenile female individuals. The composition of Bacteroidetes was stable with the gender and age of FMD. Interestingly, the relative abundance of genera Clostridiales and Bacteroidales were higher in the juvenile FMD. Conversely, proportions of Pseudomonas and Lachnospiraceae were abundant in the adult FMD. Higher proportions of Ruminococcaceae, Dore, and 5-7N15 were found in the juvenile male groups. They may reflect the different immune resistance of male and female individuals at different stages of development. This study explored the fecal microbiota composition of forest musk deer in relation to gender and age, which may provide an effective strategy for developing intestinal microecological preparations and potential musk deer breeding. [ABSTRACT FROM AUTHOR]

The organizational properties of complex lipid mixtures can give rise to functionally important structures in cell membranes. In model membranes, ternary lipid-cholesterol (CHOL) mixtures are often used as representative systems to investigate the formation and stabilization of localized structural domains (“rafts”). In this work, we describe a self-consistent mean-field model that builds on molecular dynamics simulations to incorporate multiple lipid components and to investigate the lateral organization of such mixtures. The model predictions reveal regions of bimodal order on ternary plots that are in good agreement with experiment. Specifically, we have applied the model to ternary mixtures composed of dioleoylphosphatidylcholine:18:0 sphingomyelin:CHOL. This work provides insight into the specific intermolecular interactions that drive the formation of localized domains in these mixtures. The model makes use of molecular dynamics simulations to extract interaction parameters and to provide chain configuration order parameter libraries. [ABSTRACT FROM AUTHOR]

The Chinese forest musk deer (Moschus berezovskii) is an economically important species distributed throughout southwest China and northern Vietnam. Occurrence and development of disease are aggravated by inbreeding and genetic diversity declines in captive musk deer populations. Deep transcriptomics investigation may provide a promising way to improve genetic health of captive and wild FMD population. MicroRNAs (miRNAs), which regulate gene expression by targeting and suppressing of mRNAs, play an important role in physiology and organism development control. In this study, RNA-seq technology was adopted to characterize the miRNA transcriptome signature among six tissues (heart, liver, spleen, lung, kidney, and muscle) in Chinese forest musk deer at two years of age. Deep sequencing generated a total of 103,261,451 (~87.87%) good quality small RNA reads; of them 6,622,520 were unique across all six tissues. A total of 2890 miRNAs were identified, among them 1129 were found to be expressed in all tissues. Moreover, coexpression of 20 miRNAs (>2000RPM) in all six tissues and top five highly expressed miRNAs in each tissue implied the crucial and particular function of them in FMD physiological processes. Our findings of forest musk deer miRNAs supplement the database of transcriptome information for this species and conduce to our understanding of forest musk deer biology. [ABSTRACT FROM AUTHOR]

A structure‐based statistical potential is developed for transcription factor binding site (TFBS) prediction. Besides the direct contact between amino acids from TFs and DNA bases, the authors also considered the influence of the neighbouring base. This three‐body potential showed better discriminate powers than the two‐body potential. They validate the performance of the potential in TFBS identification, binding energy prediction and binding mutation prediction. [ABSTRACT FROM AUTHOR]

Herein, aptamer-based quantum-dot detectors of K^+ made of two-different K^+ aptamers are compared. These deoxyribonucleic acid-based aptamers are TBA (5^\prime GGT TGG TGT GGT TGG 3^\prime) and AG3 (5^\prime GGG TTA GGG TTA GGG TTA GGG 3^\prime). The nanoscale aptamer-quantum-dot-based detectors described in this paper are synthesized and tested in DI water aliquots that contain KCl. The results including data suggest that beacons made of AG3 and TBA serve better as an ion indicator in different potassium level regions. As a result, aptamer beacon made of AG3 has better potential in the design of take-home diagnostic devices for hyperkalemia and hypokalemia. [ABSTRACT FROM PUBLISHER]

Abstract: Three new germacrane sesquiterpenes (1), (2), (3), along with eleven known sesquiterpenes, namely, tirotundin-3-O-methyl ether (4), deacetylvguiestin (5), 1β-hydroxydiversifolin-3-O-methyl ether (6), tagitinin C (7), 1β-hydroxytirotundin-3-O-methyl ether (8), 1β-hydroxytirotundin-1,3-O-dimethyl ether (9), tagitinin F-3-O-methyl ether (10), tagitinin F (11), tagitinin A (12), 3β-acetoxy-4α-hydroxyeduesm-11(13)-en-12-oic acid (13) and ilicic acid (14) were isolated from the aerial parts of Tithonia diversifolia. Their structures were established by spectroscopic analysis, while the relative configuration of compound 1 was confirmed by X-ray diffraction analysis. In addition, compounds 1–14 were evaluated in vitro for their anti-hyperglycemic activity by glucose uptake in 3T3-L1 adipocytes. It was found that 10μg/mL 1, 3, 6 and 8 could significantly increase glucose uptake without significant toxic effects. [Copyright &y& Elsevier]

Abstract: Conjugated linoleic acids (CLA) are found naturally in dairy products. Two isomers of CLA, that differ only in the location of cis and trans double bonds, are found to have distinct and different biological effects. The cis 9 trans 11 (C9T11) isomer is believed to have anti-carcinogenic effects, while the trans 10 cis 12 (T10C12) isomer is believed to be associated with anti-obesity effects. In this paper we extend earlier molecular dynamics (MD) simulations of pure CLA–phosphatidylcholine bilayers to investigate the comparative effects of cholesterol on bilayers composed of the two respective isomers. Simulations of phosphatidylcholine lipid bilayers in which the sn-2 chains contained one of the two isomers of CLA were performed in which, for each isomer, the simulated bilayers contained 10% and 30% cholesterol (Chol). From MD trajectories we calculate and compare structural properties of the bilayers, including areas per molecule, thickness of bilayers, tilt angle of cholesterols, order parameter profiles, and one and two-dimensional radial distribution function (RDF), as functions of Chol concentration. While the structural effect of cholesterol is approximately the same for both isomers, we find differences at an atomistic level in order parameter profiles and in two-dimensional radial distribution functions. [Copyright &y& Elsevier]

Abstract: Conjugated linoleic acids (CLA) are found naturally in dairy products. Two isomers of CLA, that differ only in the location of cis and trans double bonds, are found to have distinct and different biological effects. The cis 9 trans 11 (C9T11) isomer is attributed to have the anti-carcinogenic effects, while the trans 10 cis 12 (T10C12) isomer is believed to be responsible for the anti-obesity effects. Since dietary CLA are incorporated into membrane phospholipids, we have used Molecular Dynamics (MD) simulations to investigate the comparative effects of the two isomers on lipid bilayer structure. Specifically, simulations of phosphatidylcholine lipid bilayers in which the sn-2 chains contained one of the two isomers of CLA were performed. Force field parameters for the torsional potential of double bonds were obtained from ab initio calculations. From the MD trajectories we calculated and compared structural properties of the two lipid bilayers, including areas per molecule, density profiles, thickness of bilayers, tilt angle of tail chains, order parameters profiles, radial distribution function (RDF) and lateral pressure profiles. The main differences found between bilayers of the two CLA isomers, are (1) the order parameter profile for C9T11 has a dip in the middle of sn-2 chain while the profile for T10C12 has a deeper dip close to terminal of sn-2 chain, and (2) the lateral pressure profiles show differences between the two isomers. Our simulation results reveal localized physical structural differences between bilayers of the two CLA isomers that may contribute to different biological effects through differential interactions with membrane proteins or cholesterol. [Copyright &y& Elsevier]

Epicauta apteraKaszab(E. aptera), an endangered species used to extract cantharidin in Chinese traditional medicine, has a limited geographical distribution in the southwest China. The complete mitochondrial genome ofE. apterais 15 645bp which contains an A + T rich region and 37 genes, including 13 protein-coding genes, 22 tRNA genes and two rRNA genes (GenBank accession No. KX023302). All protein-coding genes are initiated by ATN start codon. Moreover, the largest non-coding A + T-rich region with a length of 1039 bp is at the end of 12S rRNA. It is the first report involved in the complete mitochondrial genome ofE. aptera. [ABSTRACT FROM PUBLISHER]

Abstract: The human severe acute respiratory syndrome coronavirus (SARS-CoV) and the NL63 coronaviruses are human respiratory pathogens for which no effective antiviral treatment exists. The papain-like cysteine proteases encoded by the coronavirus (SARS-CoV: PLpro; NL63: PLP1 and PLP2) represent potential targets for antiviral drug development. Three recent inhibitor-bound PLpro structures highlight the role of an extremely flexible six-residue loop in inhibitor binding. The high binding site plasticity is a major challenge in computational drug discovery/design efforts. From conventional molecular dynamics and accelerated molecular dynamics (aMD) simulations, we find that with conventional molecular dynamics simulation, PLpro translationally samples the open and closed conformation of BL2 loop on a picosecond–nanosecond timescale but does not reproduce the peptide bond inversion between loop residues Tyr269 and Gln270 that is observed on inhibitor GRL0617 binding. Only aMD simulation, starting from the closed loop conformation, reproduced the 180° ϕ–ψ dihedral rotation back to the open loop state. The Tyr–Gln peptide bond inversion appears to involve a progressive conformational change of the full loop, starting at one side, and progressing to the other. We used the SARS-CoV apo X-ray structure to develop a model of the NL63-PLP2 catalytic site. Superimposition of the PLP2 model on the PLpro X-ray structure identifies binding site residues in PLP2 that contribute to the distinct substrate cleavage site specificities between the two proteases. The topological and electrostatic differences between the two protease binding sites also help explain the selectivity of non-covalent PLpro inhibitors. [Copyright &y& Elsevier]

Forest musk deer is the most important animal for natural musk production, and the musk composition changes periodically during musk secretion, accompanied by variation in the com-position of deer-symbiotic bacteria. GC-MS and 16S rRNA sequencing were conducted in this study, the dynamic changes to correlated chemical composition and the microbiota across musk secretion periods (prime musk secretion period, vigorous musk secretion period and late musk secretion period) were investigated by integrating its serum testosterone level in different mating states. Results showed that the testosterone level, musk composition and microbiota changed with annual cycle of musk secretion and affected by its mating state. Muscone and the testosterone level peaked at vigorous musk secretion period, and the microbiota of this stage was distinct from the other 2 periods. Actinobacteria, Firmicutes and Proteobacteria were dominant bacteria across musk secretion period. PICRUSt analysis demonstrated that bacteria were ubiquitous in musk pod and involved in the metabolism of antibiotics and terpenoids in musk. "Carbohydrates and amino acids," "fatty acids and CoA" and "secretion of metabolites" were enriched at 3 periods, respectively. Pseudomonas , Corynebacterium , Clostridium , Sulfuricurvum were potential biomarkers across musk secretion. This study provides a more comprehensive understanding of genetic mechanism during musk secretion, emphasizing the importance of Actinobacteria and Corynebacterium in the synthesis of muscone and etiocholanone during musk secretion, which required further validation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xu, Li, Liu, Ma, Feng, Zhao, Zeng, Li and Jie.)

Schizophrenia is an unexplained, complex and serious mental illness. Blonanserin (BNS) is a new antipsychotic drug widely used in the treatment of schizophrenia. However, large-scale clinical studies have not been conducted in China. A multi-center, prospective, open-label, 12-week surveillance was carried out to evaluate the safety and effectiveness of BNS in patients with schizophrenia in China. Safety assessments included adverse drug reactions (ADRs), extrapyramidal symptoms (EPS), akathisia, concomitant medications for EPS by the end of treatment, and the changes in body weight from baseline by the end of treatment. The effectiveness was evaluated by the Brief Psychiatric Rating Scale (BPRS). From September 2018 to May 2020, of the 1,060 patients enrolled, 1,018 were included in the full analysis set (FAS) and safety set (SS), respectively. ADRs were developed in 205 patients among the included, the incidence being 20.1%. ADRs of EPS occurred in 169 patients, the incidence being 16.6%, ADRs of akathisia occurred in 90 patients, the incidence being 8.8%; concomitant therapeutic and prophylactic agents for EPS accounts for 19.2%; 4.0% of patients had a ≥7% increase in body weight from baseline at 12 weeks after initiating treatment. Using the last-observation-carried-forward (LOCF) method, the changes in total BPRS scores were -11.2 ± 10.17 ( N = 1,018), -16.8 ± 12.69 ( N = 1,018) and -20.6 ± 13.99 ( N = 1,018) after 2/4, 6/8, or 12 weeks, respectively. 53.5% (545/1,018) patients showed response to blonanserin treatment in week 12. The post-marketing surveillance results of BNS demonstrates safety profile and effectiveness of the drug., Competing Interests: The authors declare that this study received funding from Sumitomo Pharma Co., Ltd. and Sumitomo Pharma (Suzhou) Co., Ltd. The funder had the following involvement in the study: the study design and the analysis., (Copyright © 2022 Wu, Wang, Liu, Sang, Bo, Yang, Xun, Li, Zhang, Sun, Cai, Deng, Zhao, Li, Liu, Zhan and Chen.)

β654-thalassemia is a prominent Chinese subtype of b-thalassemia, representing 17% of all cases of β-thalassemia in China. The molecular mechanism underlying this subtype involves the IVS-2-654 C→T mutation leading to aberrant β-globin RNA splicing. This results in an additional 73-nucleotide exon between exons 2 and 3 and leads to a severe thalassemia syndrome. Herein, we explored a CRISPR/Cas9 genome editing approach to eliminate the additional 73- nucleotide by targeting both the IVS-2-654 C→T and a cryptic acceptor splice site at IVS-2-579 in order to correct aberrant b-globin RNA splicing and ameliorate the clinical β-thalassemia syndrome in β654 mice. Gene-edited mice were generated by microinjection of sgRNA and Cas9 mRNA into one-cell embryos of β654 or control mice: 83.3% of live-born mice were gene-edited, 70% of which produced correctly spliced RNA. No off-target events were observed. The clinical symptoms, including hematologic parameters and tissue pathology of all of the edited β654 founders and their offspring were significantly improved compared to those of the non-edited β654 mice, consistent with the restoration of wild-type b-globin RNA expression. Notably, the survival rate of gene-edited heterozygous β654 mice increased significantly, and liveborn homozygous β654 mice were observed. Our study demonstrated a new and effective gene-editing approach that may provide groundwork for the exploration of β654-thalassemia therapy in the future.

Background: The formation of musk is a complex biophysical and biochemical process that change with the rut of male forest musk deer. We have reported that the mating status of male forest musk deer might result to the variations of chemical composition and microbiota of musk and its yields. Critical roles for microRNAs (miRNAs) of multi-tissues were profiled in our previous study; however, the role for miRNAs of the musk gland remains unclear in this species., Methods: In this study, we used Illumina deep sequencing technology to sequence the small RNA transcriptome of unmated male (UM) and mated male (UM) of Chinese forest musk deer., Results: We identified 1,652 known miRNAs and 45 novel miRNAs, of which there were 174 differentially expressed miRNAs between UM and MM. chi-miR-21-5p, ipu-miR-99b and bta-miR-26a were up-regulated in UM among the 10 most differentially expressed miRNAs. Functional enrichment of the target genes showed that monosaccharide biosynthetic process, protein targeting, cellular protein catabolic process enriched higher in MM. Meanwhile, structural molecule activity, secretion by cell, regulated exocytosis and circulatory system process enriched more in UM, hinting that the formation of musk in UM was mediated by target genes related to exocytosis. The miRNA-mRNA pairs such as miR-21: CHD7 , miR143: HSD17B7 , miR-141/200a: Noc2 might involve in musk gland development and musk secretion, which need to be verified in future study., Competing Interests: The authors declare there are no competing interests., (©2021 Jie et al.)

Objectives: We aimed to characterise the microbial changes associated with histological stages of gastric tumourigenesis., Design: We performed 16S rRNA gene analysis of gastric mucosal samples from 81 cases including superficial gastritis (SG), atrophic gastritis (AG), intestinal metaplasia (IM) and gastric cancer (GC) from Xi'an, China, to determine mucosal microbiome dysbiosis across stages of GC. We validated the results in mucosal samples of 126 cases from Inner Mongolia, China., Results: We observed significant mucosa microbial dysbiosis in IM and GC subjects, with significant enrichment of 21 and depletion of 10 bacterial taxa in GC compared with SG (q<0.05). Microbial network analysis showed increasing correlation strengths among them with disease progression (p<0.001). Five GC-enriched bacterial taxa whose species identifications correspond to Peptostreptococcus stomatis , Streptococcus anginosus , Parvimonas micra , Slackia exigua and Dialister pneumosintes had significant centralities in the GC ecological network (p<0.05) and classified GC from SG with an area under the receiver-operating curve (AUC) of 0.82. Moreover, stronger interactions among gastric microbes were observed in Helicobacter pylori -negative samples compared with H. pylori -positive samples in SG and IM. The fold changes of selected bacteria, and strengths of their interactions were successfully validated in the Inner Mongolian cohort, in which the five bacterial markers distinguished GC from SG with an AUC of 0.81., Conclusions: In addition to microbial compositional changes, we identified differences in bacterial interactions across stages of gastric carcinogenesis. The significant enrichments and network centralities suggest potentially important roles of P. stomatis , D. pneumosintes , S. exigua , P. micra and S. anginosus in GC progression., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Protein-DNA interactions are involved in many essential biological processes such as transcription, splicing, replication and DNA repair. It is of great value to identify DNA-binding proteins as well as their binding sites in order to study the mechanisms of these biological processes. A number of experimental methods have been developed for the identification of DNA-binding proteins, such as DNAase foot printing, EMSA, X-ray crystallography, NMR spectroscopy and CHIP-on-Chip. However, with the increasingly greater number of suspected protein-DNA interactions, identification by experimental methods is expensive, labor-intensive and time-consuming. Hence, in the past decades researchers have developed many computational approaches to predict in silico the interactions of proteins and DNA. Machine learning technology has been widely used and become dominant in this field. In this article, we focus on reviewing recent machine learning-based progresses in DNA-binding protein and binding residue prediction methods, the most commonly used features in these predictions, machine learning classifier comparison and selection, evaluation method comparison, and existing problems and future directions for the field.

The connection between membrane inhomogeneity and the structural basis of lipid rafts has sparked interest in the lateral organization of model lipid bilayers of two and three components. In an effort to investigate anisotropic lipid distribution in mixed bilayers, a self-consistent mean-field theoretical model is applied to palmitoyloleoylphosphatidylcholine (POPC)--palmitoyl sphingomyelin (PSM)--cholesterol mixtures. The compositional dependence of lateral organization in these mixtures is mapped onto a ternary plot. The model utilizes molecular dynamics simulations to estimate interaction parameters and to construct chain conformation libraries. We find that at some concentration ratios the bilayers separate spatially into regions of higher and lower chain order coinciding with areas enriched with PSM and POPC, respectively. To examine the effect of the asymmetric chain structure of POPC on bilayer lateral inhomogeneity, we consider POPC-lipid interactions with and without angular dependence. Results are compared with experimental data and with results from a similar model for mixtures of dioleoylphosphatidylcholine, steroyl sphingomyelin, and cholesterol.

Gene regulation requires specific protein-DNA interactions. Detecting the short and variable DNA sequences in gene promoter regions to which transcription factors (TF) bind is a difficult challenge in bioinformatics. Here we have developed two-body and three-body interaction potentials that are able to assess protein-DNA interaction and achieve a higher level of specificity in the recognition of TF-binding sites. The potentials were calculated using experimentally characterized 3-D structures of protein-DNA complexes. We implemented two approaches in order to evaluate the potentials. Using the first method, we calculated the Z-score of the potential energy of a true TF-binding sequence when compared to 50,000 randomly generated DNA sequences. The second method allowed us to take advantage of the ability of statistical potentials to recognize novel TF-binding sites within the promoter region of genes. We found that the three-body potential, which takes into account the interaction between a DNA base and a protein residue with regard to the effect of a neighboring DNA base, had a better average Z-score than that of the two-body potential. This neighbor effect suggests that the local conformation of DNA does play a critical role in specific residue-base recognition. In all cases, the potentials developed here outperformed published results. The two sets of potentials were tested further by applying them in genome-scale TF-binding site prediction for the CRP protein in E. coli. Out of the 142 cases, 28% of the true binding sites ranked first (i.e.

A key component in protein structure prediction is the development of potentials that can discriminate native or near native structures from the wrong ones. Most previously developed statistical potentials are based on the preferred distances between any pair of residues. Here we explore the possible angle dependence between pairs of residues in addition to their distance dependence. For simplicity, we used a grid based partition of the space and analyzed relative geometric propensity between protein residue pairs. One thousand and nine non-redundant protein structures are studied in this paper. We have attached a local coordinate system to each amino acid, and spatial distributions of its nearby residues are investigated. Within the same distance range, there are clear differences in various grids. We have further developed a grid-based statistical potential, which incorporates both the distance dependence and angle dependence using a quasi-chemical approximation. The potential is tested against 32 decoy sets, and in 25 cases the native structure has the best score. This performance is comparable and in two cases better than best performance from previously developed distance-dependent statistical potentials on residue and atom level.

Annotation of the functional sites on the surface of a protein has been the subject of many studies. In this regard, the search for attributes and features characterizing these sites is of prime consequence. Here, we present an implementation of a kernel-based machine learning protocol for identifying residues on a DNA-binding protein form the interface with the DNA. Sequence and structural features including solvent accessibility, local composition, net charge and electrostatic potentials are examined. These features are then fed into Support Vector Machines (SVM) to predict the DNA-binding residues on the surface of the protein. In order to compare with published work, we predict binding residues by training on other binding and non-binding residues in the same protein for which we achieved an accuracy of 79%. The sensitivity and specificity are 59% and 89%. We also consider a more realistic approach, predicting the binding residues of proteins entirely withheld from the training set achieving values of 66%, 43% and 81%, respectively. Performances reported here are better than other published results. Moreover, since our protocol does not lean on sequence or structural homology, it can be used to annotate unclassified proteins and more generally to identify novel binding sites with no similarity to the known cases.