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ObjectiveRevealing the single-cell immune ecosystems in true versus de novo hepatocellular carcinoma (HCC) recurrences could help the optimal development of immunotherapies.DesignWe performed 5’and VDJ single-cell RNA-sequencing on 34 samples from 20 recurrent HCC patients. Bulk RNA-sequencing, flow cytometry, multiplexed immunofluorescence, and in vitro functional analyses were performed on samples from two validation cohorts.ResultsAnalyses of mutational profiles and evolutionary trajectories in paired primary and recurrent HCC samples using whole-exome sequencing identified de novo versus true recurrences, some of which occurred before clinical diagnosis. The tumour immune microenvironment (TIME) of truly recurrent HCCs was characterised by an increased abundance in KLRB1+CD8+T cells with memory phenotype and low cytotoxicity. In contrast, we found an enrichment in cytotoxic and exhausted CD8+T cells in the TIME of de novo recurrent HCCs. Transcriptomic and interaction analyses showed elevated GDF15 expression on HCC cells in proximity to dendritic cells, which may have dampened antigen presentation and inhibited antitumour immunity in truly recurrent lesions. In contrast, myeloid cells’ cross talk with T cells-mediated T cell exhaustion and immunosuppression in the TIME ofde novorecurrent HCCs. Consistent with these findings, a phase 2 trial of neoadjuvant anti-PD-1 immunotherapy showed more responses in de novo recurrent HCC patients.ConclusionTrue and de novo HCC recurrences occur early, have distinct TIME and may require different immunotherapy strategies. Our study provides a source for genomic diagnosis and immune profiling for guiding immunotherapy based on the type of HCC recurrence and the specific TIME.

In recent years, image fusion has been a research hotspot. However, it is still a big challenge to balance the problems of noiseless image fusion and noisy image fusion. In order to improve the weak performance and low robustness of existing image fusion algorithms in noisy images, an infrared and visible image fusion algorithm based on optimized low-rank matrix factorization with guided filtering is proposed. First, the minimized error reconstruction factorization is introduced into the low-rank matrix, which effectively enhances the optimization performance, and obtains the base image with good filtering performance. Then using the base image as the guide image, the source image is decomposed into the high-frequency layer containing detail information and noise, and the low-frequency layer containing energy information through guided filtering. According to the noise intensity, the sparse reconstruction error is adaptively obtained to fuse the high-frequency layers, and the weighted average strategy is utilized to fuse the low-frequency layers. Finally, the fusion image is obtained by reconstructing the pre-fused high-frequency layer and the pre-fused low-frequency layer. The comparative experiments show that the proposed algorithm not only has good performance for noise-free images, but more importantly, it can effectively deal with the fusion of noisy images.

Image registration is the base of subsequent image processing and has been widely utilized in computer vision. Aiming at the differences in the resolution, spectrum, and viewpoint of infrared and visible images, and in order to accurately register infrared and visible images, an automatic robust infrared and visible image registration algorithm, based on a deep convolutional network, was proposed. In order to precisely search and locate the feature points, a deep convolutional network is introduced, which solves the problem that a large number of feature points can still be extracted when the pixels of the infrared image are not clear. Then, in order to achieve accurate feature point matching, a rough-to-fine matching algorithm is designed. The rough matching is obtained by location orientation scale transform Euclidean distance, and then, the fine matching is performed based on the update global optimization, and finally, the image registration is realized. Experimental results show that the proposed algorithm has better robustness and accuracy than several advanced registration algorithms.

Identifying more missing proteins (MPs) is an important mission of C-HPP. With the number of identified MPs being attenuated year by year (2,949 to 2,129 MPs from 2016 to 2019), we have realized that the difficulty of exploring the remaining MPs is a challenge in technique. Herein, we propose a comprehensive strategy to effectively enrich, separate, and identify proteins with low molecular weights, aiming at the discovery of MPs. Basically, a protein extract from human placenta was passed through a C18 SPE column, and the bound proteins that were eluted were further separated with an SDS-PAGE gel or a 50 kDa cutoff filter. The separated proteins were subjected to trypsin digestion, and the MS/MS signals were searched against data sets with two different digestion modes (full-trypsin and semitrypsin). The strategy was adopted, resulting in the identification of 4 MPs with 8 unique peptides (≥2 non-nested unique peptides with ≥9 amino acids). Importantly, the identification of 6 out of 8 of the unique peptides derived from the MPs was further supported by parallel reaction monitoring, which confirmed the identification of 3 MPs from human placenta tissues (Q6NT89: TMF-regulated nuclear protein 1; A0A183: late cornified envelope protein 6A; and Q6UWQ7: insulin growth factor-like family member 2, mapped to chromosomes 1, 1, and 19, respectively). The three proteins ranged in length from 80 aa to 227 aa. The study not only establishes a feasible strategy for analyzing proteins with low molecular weights but also fills a small part of a large gap in the list of MPs. The data obtained in this study are available via ProteomeXchange (PXD014083) and PeptideAtlas (PASS01389).

Bisecting N-acetylglucosamine (GlcNAc), a GlcNAc linked to the core β-mannose residue via a β1,4 linkage, is a special type of N-glycosylated modification that has been reported to be involved in various biological processes, such as cell adhesion and fetal development. This N-glycan structure was found to be abundant in human trophoblasts; it was postulated to be resistant to natural killer cell-mediated cytotoxicity, enabling a mother to nourish a fetus without rejection. In this study, we hypothesized that the human amniotic membrane, which serves as the last barrier for the fetus, may also express bisected-type glycans. To test this hypothesis, glycomic analysis of the human amniotic membrane was performed, and bisected N-glycans were detected. Further, our proteomic data, which has been previously employed to explore human missing proteins, were analyzed and the presence of bisecting GlcNAc peptides was confirmed. A total of 41 glycoproteins with 43 glycopeptides were found to possess a bisecting GlcNAc, and 25 of these glycoproteins were reported to exhibit this type of modification for the first time. These results provide insights for implementing bisecting GlcNAc modification in the human amniotic membrane, and can be beneficial to functional studies on glycoproteins with bisecting GlcNAc modifications and functional studies on immune suppression in human placenta.

It is acknowledged that the bisecting N-acetylglucosamine (GlcNAc) structure, a GlcNAc linked to the core β-mannose residue via a β1,4 linkage, represents a special type of N-glycosylated modification and has been reported to be involved in various biological processes, such as cell adhesion and fetal development. Clark et al. has found that the majority of N-glycans in human trophoblasts bearing a bisecting GlcNAc. This type of glycan has been reported to help trophoblasts get resistant to natural killer (NK) cell-mediated cytotoxicity, and this would provide a possible explanation for the question how could the mother nourish a fetus within herself without rejection. Herein, we hypothesized that human amniotic membrane which is the last barrier for the fetus may also express bisecting type glycans to protect the fetus. To test this hypothesis, glycomic analysis of human amniotic membrane was performed, and the bisecting N-glycans with high abundance were detected. In addition, we re-analyzed our proteomic data with high fractionation and amino acid sequence coverage from human amniotic membrane, which had been released for the exploration of human missing proteins. The presence of bisecting GlcNAc peptides was revealed and confirmed. A total of 41 glycoproteins with 43 glycopeptides were found to possess a bisecting GlcNAc, 25 of which are for the first time to be reported to have this type of modification. These results provide the profiling of bisecting GlcNAc modification in human amniotic membrane and benefit to the function studies of glycoproteins with bisecting GlcNAc modification and the function studies in immune suppression of human placenta. The mass spectrometry placenta data are available via ProteomeXchange (PXD010630).

High specificity of trypsin is a prerequisite for accurate identification and quantification of proteins in shotgun proteomics. It is important to minimize nonspecific enzymatic cleavages during proteomic sample preparation. Methods In this study, protein extraction and trypsin digestion conditions were extensively evaluated using the less-complex Escherichia coli lysates to improve the sensitivity of detecting low-abundance nonspecific peptides by liquid chromatography/tandem mass spectrometry. Results Trypsin digestion buffers and digestion times were proved to have a significant effect on nonspecific cleavages. The triethylammonium bicarbonate buffer induces significantly lower nonspecific cleavages than the other two buffers, but a freshly prepared urea solution does not induce more than sodium dodecyl sulfate. Because prolonged trypsin digestion resulted in a considerable number of nonspecific cleavages, an optimized 2-h protocol was developed with 45.2% less semispecific tryptic peptides but 18.5% more unmodified peptides identified than the commonly used 16-h protocol. Conclusions The significant decrease in nonspecific cleavages and artificial modifications improves the accuracy of protein quantification and the identification of low-abundance proteins, and it is especially useful for studying protein posttranslational modifications. For trypsin digestion, the proposed 2-h protocol can potentially be a replacement for the traditional 16-h protocol.

Following an enormous effort by the global scientific community coordinated by HUPO's Human Proteome Project, the number of proteins without high-quality MS or other evidence (colloquially termed missing proteins) has substantially decreased; however, some highly hydrophobic MPs remain on the list. We believe that efficient peptide separation is an approach that can be used to improve the identification of these hydrophobic MPs. We propose that peptides prepared from the membrane fractions of human cell lines and placental tissue can be well separated from hydrophilic peptides in organic solvents at high concentrations due to the precipitation of hydrophilic peptides with lower solubility. Using a combination strategy of peptide separation in 98% acetonitrile prior to traditional 2D reverse-phase liquid chromatography, more hydrophobic peptides were detected in the supernatants of the organic solvent extractions than were found in the pellets. When this strategy was adopted, 30 MPs (≥2 non-nested unique peptides with ≥9 amino acids) with 114 unique peptides were identified at protein false discovery rate (FDR) < 1%, including 7, 12, and 13 MPs obtained from membrane preparations derived from K562, HeLa cells, and human placenta, respectively. Of the 30 MPs identified in this study, 19 were categorized as membrane proteins or extracellular matrix proteins. Furthermore, 20 were verified to possess two non-nested unique peptides through parallel reaction monitoring with the corresponding chemically synthesized peptides. The use of organic solvents at high concentrations was shown to be an efficient way to improve the exploration of hydrophobic MPs. The data obtained in this study are available via ProteomeXchange (PXD010630) and PeptideAtlas (PASS01218).

Currently, the commercial reagents for isobaric peptides labeling (TMT and iTRAQ) have some drawbacks, such as high cost in experiments, especially in quantitation for the modified peptides, and inconvenient handling for variable sizes of samples. Herein, we developed a set of 10-plex isobaric tags (IBT) with high stability and low cost. The labeled peptides were sensitively detected on Orbitrap Q Exactive MS with an MS2 resolution of 35 000 at 30% NCE, while the peptides were efficiently labeled over 97% by IBT at a ratio of 10:1 of reagent/peptide (w/w) in 200 mM TEAB buffer for 2 h. The IBT labeling was demonstrated with a wide dynamic range of 50-fold without obvious matrix effects on quantification. Importantly, there was little quantification bias found among the individual IBT tags, indicating that the peptides labeled by different tags were quantitatively comparable. The IBT 10-plex reagents were applied for dynamically monitoring the quantitative responses of phosphoproteome stimulated by EGF treatment in HeLa cells. In total, 5 361 unique phosphopeptides were identified, which reached a similar conclusion as others reported. The IBT reagents were therefore experimentally proven as a new type of reagents for isobaric peptides labeling and useful in a large quantity peptides of quantitative proteomics.

The mission of the Chromosome-Centric Human Proteome Project (C-HPP) to discover missing proteins (MPs) has become increasingly difficult due to the remaining low-abundance, high-hydrophobicity, or low-molecular-weight MPs. We have reported two approaches to resolve these identification problems for the low-abundance and high-hydrophobicity MPs, respectively. In this study, to improve the identification of low-abundance MPs with high hydrophobicity, we combined two approaches and obtained MPs from several different cancer cell lines. Their membrane fractions were isolated by ultracentrifugation, and the low-abundance proteins were enriched at the protein level with the ProteoMiner kit. After that, the peptides from the enriched proteins were separated by high concentrations of organic solvents according to their hydrophobicity as the first dimension of separation at the peptide level, and the second and third dimensions of separation involved a high pH reversed-phase and an acid reversed-phase column, respectively. In total, 16 MPs (at least two non-nested unique peptides with ≥9 amino acids) with 61 unique peptides were identified from four human cancer cell lines, including 2, 8, 2, and 7 MPs from HeLa, HCT116, SNU-1, and HepG2 cells, respectively. Furthermore, all MPs were verified with two non-nested unique peptides through parallel reaction monitoring (PRM) by matching the peptides with their chemically synthesized peptides. Interestingly, two additional MPs were verified from the same cell line by PRM assay, although the two non-nested unique peptides with ≥9 amino acids for each MP were identified from different MS injections or cell lines by data-dependent acquisition (DDA). Thus, a total of 18 MPs were dug out in this study. The data are available via ProteomeXchange (PXD014058) and PeptideAtlas (PASS01388).

In the field of Synthetic Aperture Radar (SAR) image interpretation, the Automatic Target Recognition (ATR) has always been the focus and hotspot in this field, which is also the research difficulty in this field. The SAR ATR is generally composed of three steps: extraction of Region of Interest (RoI), target identification, and target classification. The complex flow not only limits the efficiency of SAR ATR, but also makes the overall optimization of the model difficult to be carried out, which restricts the accuracy. This paper discusses Faster R-CNN and SSD adopted from the computer vision and shows how those approaches enable significantly improved performance for SAR ATR. The validity of the deep learning method in the field of automatic target recognition for SAR images and the nature of the university are verified, which lays the foundation for further research.

As more and more water treatment plants were built, the amount of sludge in China increases rapidly. The main method of disposing is landfill, but it will occupy a large number of lands. Co-digestion with kitchen waste is an effective way to treat sludge, but there are some problems, such as acidification. Dividing the anaerobic digestion into hydrogen production process and methane production process can solve these problems properly. In this study, a 300L continuously stirred tank reactor treating the hydrogen production residue from sludge and kitchen waste had been running for about 110 days. The reactor was operated at a temperature of 36 °C. Due to equipment problem, the reactor failed to maintain suitable temperature from the 82 nd day.PH and the concentration of TVFA were measured everyday after equipment breakdown. Total sugar, TCOD, soluble sugar, total protein and soluble protein of the feedstock were compared with that of the effluent to evaluate the performance of the reactor after breakdown. On the 102th day, the concentration of TCOD decreased from 71009mg/L to 53296mg/L, and the degradation rate was 24.9%, the concentration of total sugar and total protein respectively decreased from 9721mg/L,23373mg/L to 5357mg/L,14475mg/L, the degradation rates were 44.9% and 38.1%.

Considering the technical limitations of mass spectrometry in protein identification, the mRNAs bound to ribosomes (RNC-mRNA) are assumed to reflect the mRNAs participating in the translational process. The RNC-mRNA data are reasoned to be useful for appraising the missing proteins. A set of the multiomics data including free-mRNAs, RNC-mRNAs, and proteomes was acquired from three liver cancer cell lines. On the basis of the missing proteins in neXtProt (release 2014-09-19), the bioinformatics analysis was carried out in three phases: (1) finding how many neXtProt missing proteins have or do not have RNA-seq and/or MS/MS evidence, (2) analyzing specific physicochemical and biological properties of the missing proteins that lack both RNA-seq and MS/MS evidence, and (3) analyzing the combined properties of these missing proteins. Total of 1501 missing proteins were found by neither RNC-mRNA nor MS/MS in the three liver cancer cell lines. For these missing proteins, some are expected higher hydrophobicity, unsuitable detection, or sensory functions as properties at the protein level, while some are predicted to have nonexpressing chromatin structures on the corresponding gene level. With further integrated analysis, we could attribute 93% of them (1391/1501) to these causal factors, which result in the expression products scarcely detected by RNA-seq or MS/MS.

Centipedes are one of the oldest venomous arthropods using toxin as their weapon to capture prey. But little attention was focused on them and only few centipede toxins were demonstrated with activity on ion channels. Therefore, more deep works are needed to understand the diversity of centipede venom. In the present study, we use peptidomics combined with cDNA library to uncover the diversity of centipede Scolopendra subspinipes mutilans L. Koch. 192 peptides were identified by LC-MS/MS and 79 precursors were deduced by cDNA library. Surprisingly, the signal peptides of centipede toxins were more complicated than any other animal toxins and even exhibited large differences in homologues. Meanwhile, a large number of variants generated by alternative cleavage sites were detected by mass spectra. Odd number of cystein (3, 5, 7) found in the mature peptides were seldom seen in peptide toxins. In additional, two novel cysteine frameworks (C–C–C–CCC, C–C–C–C–CC–CC) were identified from 16 different cysteine frameworks from centipede peptides. Only 29 precursors have clear targets, while others may provide a potential diversity function for centipede. These findings highlight the extensive diversity of centipede toxins and provide powerful tools to understand the capture and defense weapon of centipede. Biological significance Peptide toxins from venomous animal have attracted increasing attentions due to their extraordinary chemical and pharmacological diversity. Centipedes are one of the most used Chinese traditional medicines, but little was known about the active components. The venom of Scolopendra subspinipes mutilans L. Koch is first deeply analyzed in this work and most of peptides were never discovered before. Interestingly, the number and arrangement of cysteine showed a larger different to known peptide toxins such spider or scorpion toxins. Moreover, only 29 peptides from this centipede venom were identified with known function. It suggested that our work not only important to understand the composition of centipede venom, but also provide many valuable peptides for potential biological functions.

Human Proteome Project (HPP) aims at mapping entire human proteins with a systematic effort upon all the emerging techniques, which would enhance understanding of human biology and lay a foundation for development of medical applications. Until now, 2563 missing proteins (MPs, PE2-4) are still undetected even using the most sensitive approach of protein detection. Herein, we propose that enrichment of low-abundance proteins benefits MPs finding. ProteoMiner is an equalizing technique by reducing high-abundance proteins and enriching low-abundance proteins in biological liquids. With triton X-100/TBS buffer extraction, ProteoMiner enrichment, and peptide fractionation, 20 MPs (at least two non-nested unique peptides with more than eight a.a. length) with 60 unique peptides were identified from four human tissues including eight membrane/secreted proteins and five nucleus proteins. Then 15 of them were confirmed with two non-nested unique peptides (≥9 a.a.) identified by matching well with their chemically synthetic peptides in PRM assay. Hence, these results demonstrated ProteoMiner as a powerful means in discovery of MPs.

Our first proteomic exploration of human chromosome 1 began in 2012 (CCPD 1.0), and the genome-wide characterization of the human proteome through public resources revealed that 32-39% of proteins on chromosome 1 remain unidentified. To characterize all of the missing proteins, we applied an OMICS-integrated analysis of three human liver cell lines (Hep3B, MHCC97H, and HCCLM3) using mRNA and ribosome nascent-chain complex-bound mRNA deep sequencing and proteome profiling, contributing mass spectrometric evidence of 60 additional chromosome 1 gene products. Integration of the annotation information from public databases revealed that 84.6% of genes on chromosome 1 had high-confidence protein evidence. Hierarchical analysis demonstrated that the remaining 320 missing genes were either experimentally or biologically explainable; 128 genes were found to be tissue-specific or rarely expressed in some tissues, whereas 91 proteins were uncharacterized mainly due to database annotation diversity, 89 were genes with low mRNA abundance or unsuitable protein properties, and 12 genes were identifiable theoretically because of a high abundance of mRNAs/RNC-mRNAs and the existence of proteotypic peptides. The relatively large contribution made by the identification of enriched transcription factors suggested specific enrichment of low-abundance protein classes, and SRM/MRM could capture high-priority missing proteins. Detailed analyses of the differentially expressed genes indicated that several gene families located on chromosome 1 may play critical roles in mediating hepatocellular carcinoma invasion and metastasis. All mass spectrometry proteomics data corresponding to our study were deposited in the ProteomeXchange under the identifiers PXD000529, PXD000533, and PXD000535.

5-methylcytosine (5-mC) can be oxidized to 5-hydroxymethylcytosine (5-hmC). Genome-wide profiling of 5-hmC thus far indicates 5-hmC may not only be an intermediate form of DNA demethylation but could also constitute an epigenetic mark per se. Here we describe a cost-effective and selective method to detect both the hydroxymethylation and methylation status of cytosines in a subset of cytosines in the human genome. This method involves the selective glucosylation of 5-hmC residues, short-Sequence tag generation and high-throughput sequencing. We tested this method by screening H9 human embryonic stem cells and their differentiated embroid body cells, and found that differential hydroxymethylation preferentially occurs in bivalent genes during cellular differentiation. Especially, our results support hydroxymethylation can regulate key transcription regulators with bivalent marks through demethylation and affect cellular decision on choosing active or inactive state of these genes upon cellular differentiation. Future application of this technology would enable us to uncover the status of methylation and hydroxymethylation in dynamic biological processes and disease development in multiple biological samples.

Snakes have numerous features distinctive from other tetrapods and a rich history of genome evolution that is still obscure. Here, we report the high-quality genome of the five-pacer viper, Deinagkistrodon acutus, and comparative analyses with other representative snake and lizard genomes. We map the evolutionary trajectories of transposable elements (TEs), developmental genes and sex chromosomes onto the snake phylogeny. TEs exhibit dynamic lineage-specific expansion, and many viper TEs show brain-specific gene expression along with their nearby genes. We detect signatures of adaptive evolution in olfactory, venom and thermal-sensing genes and also functional degeneration of genes associated with vision and hearing. Lineage-specific relaxation of functional constraints on respective Hox and Tbx limb-patterning genes supports fossil evidence for a successive loss of forelimbs then hindlimbs during snake evolution. Finally, we infer that the ZW sex chromosome pair had undergone at least three recombination suppression events in the ancestor of advanced snakes. These results altogether forge a framework for our deep understanding into snakes' history of molecular evolution., Snakes have many characteristics that distinguish them from their relatives. Here, Yin et al. sequence the genome of the five-pacer viper, Deinagkistrodon acutus, and use comparative genomic analyses to elucidate the evolution of transposable elements, developmental genes and sex chromosomes in snakes.

Background The venom of predatory marine cone snails mainly contains a diverse array of unique bioactive peptides commonly referred to as conopeptides or conotoxins. These peptides have proven to be valuable pharmacological probes and potential drugs because of their high specificity and affinity to important ion channels, receptors and transporters of the nervous system. Most previous studies have focused specifically on the conopeptides from piscivorous and molluscivorous cone snails, but little attention has been devoted to the dominant vermivorous species. Results The vermivorous Chinese tubular cone snail, Conus betulinus, is the dominant Conus species inhabiting the South China Sea. The transcriptomes of venom ducts and venom bulbs from a variety of specimens of this species were sequenced using both next-generation sequencing and traditional Sanger sequencing technologies, resulting in the identification of a total of 215 distinct conopeptides. Among these, 183 were novel conopeptides, including nine new superfamilies. It appeared that most of the identified conopeptides were synthesized in the venom duct, while a handful of conopeptides were identified only in the venom bulb and at very low levels. Conclusions We identified 215 unique putative conopeptide transcripts from the combination of five transcriptomes and one EST sequencing dataset. Variation in conopeptides from different specimens of C. betulinus was observed, which suggested the presence of intraspecific variability in toxin production at the genetic level. These novel conopeptides provide a potentially fertile resource for the development of new pharmaceuticals, and a pathway for the discovery of new conotoxins. Electronic supplementary material The online version of this article (doi:10.1186/s13742-016-0122-9) contains supplementary material, which is available to authorized users.

Fish venom remains a virtually untapped resource. There are so few fish toxin sequences for reference, which increases the difficulty to study toxins from venomous fish and to develop efficient and fast methods to dig out toxin genes or proteins. Here, we utilized Chinese yellow catfish (Pelteobagrus fulvidraco) as our research object, since it is a representative species in Siluriformes with its venom glands embedded in the pectoral and dorsal fins. In this study, we set up an in-house toxin database and a novel toxin-discovering protocol to dig out precise toxin genes by combination of transcriptomic and proteomic sequencing. Finally, we obtained 15 putative toxin proteins distributed in five groups, namely Veficolin, Ink toxin, Adamalysin, Za2G and CRISP toxin. It seems that we have developed a novel bioinformatics method, through which we could identify toxin proteins with high confidence. Meanwhile, these toxins can also be useful for comparative studies in other fish and development of potential drugs.

Understanding the oxidation process of Cr/Cu/Cr laminated thin film electrode is important for developing new oxidation-resistant electrodes. By studying the evolution of crystal structure, morphology and electric resistivity of Cr/Cu/Cr thin films and electrodes that were post-annealed at different temperatures, the oxidation mechanism and process of Cr/Cu/Cr electrode were proposed. Copper is first oxidized into Cu 2 O at low temperatures ( 310 °C). As a result, the passivation of Cu metal at electrode sidewalls is crucial in reducing oxidation of Cr/Cu/Cr electrodes or designing new copper-containing oxidation-resistant electrodes.

Background Differences in 5-hydroxymethylcytosine, 5hmC, distributions may complicate previous observations of abnormal cytosine methylation statuses that are used for the identification of new tumor suppressor gene candidates that are relevant to human hepatocarcinogenesis. The simultaneous detection of 5-methylcytosine and 5-hydroxymethylcytosine is likely to stimulate the discovery of aberrantly methylated genes with increased accuracy in human hepatocellular carcinoma. Results Here, we performed ultra-performance liquid chromatography/tandem mass spectrometry and single-base high-throughput sequencing, Hydroxymethylation and Methylation Sensitive Tag sequencing, HMST-seq, to synchronously measure these two modifications in human hepatocellular carcinoma samples. After identification of differentially methylated and hydroxymethylated genes in human hepatocellular carcinoma, we integrate DNA copy-number alterations, as determined using array-based comparative genomic hybridization data, with gene expression to identify genes that are potentially silenced by promoter hypermethylation. Conclusions We report a high enrichment of genes with epigenetic aberrations in cancer signaling pathways. Six genes were selected as tumor suppressor gene candidates, among which, ECM1, ATF5 and EOMES are confirmed via siRNA experiments to have potential anti-cancer functions. Electronic supplementary material The online version of this article (doi:10.1186/s13059-014-0533-9) contains supplementary material, which is available to authorized users.

To investigate the protective effects of valproic acid (VPA) on myocardium in rats following lethal burn injury and its mechanism.Seventy-eight Sprague-Dawley (SD) rats were randomly assigned to four groups: sham-scald group (n=10), sham-scald + VPA group (n=10), scald group (n=29), and scald + VPA group (n=29). Rats in the latter two groups were subjected to 55% total body surface area (TBSA) third-degree burns by immersing the back of the trunk for 15 seconds, both lower extremities for 15 seconds, and the abdomen for 8 seconds in 80 centigrade water. Sham-scald rats were immersed in 37 centigrade water instead. Rats were then subcutaneously injected with VPA (300 mg/kg) or normal saline as control. Blood of 5 rats in each group was with drawn from the abdominal aorta at 6 hours after injury for measurement of plasma creatine kinase-MB (CK-MB) activities; then the rats were sacrificed and heart tissues were harvested for the measurement of acetylated histone H3 and activated caspase-3 by Western Blot. The remaining rats were used for 12-hour survival analysis.Compared with sham-scald group, there was a significant increase in plasma CK-MB activities (5 438.0 ± 413.6 U/L vs. 2 881.0 ± 324.8 U/L, P0.05) and activated caspase-3 protein levels in heart tissue (gray value: 1.75 ± 0.25 vs. 1.00 ± 0.18, P0.05) and an significant decline in the acetylation levels of histone H3 (gray value: 0.55 ± 0.18 vs. 1.00 ± 0.20, P0.05) after major burn injury. VPA treatment significantly reduced the plasma CK-MB activities [(4 018.0 ± 388.3) U/L], activated caspase-3 protein levels in heart tissue (gray value: 1.33 ± 0.20), and raised the acetylation levels of histone H3 (gray value: 2.20 ± 0.23, all P0.05). Survival analysis by Kaplan-Meier curves showed that the survival was improved after VPA treatment, and the survival rate was increased from 0 to 50% at 12 hours (P0.05).VPA can attenuate cardiac injury and improve survival in a rodent model of lethal burn injury. These protective effects may be due to its inhibitory effects on histone deacetylase and caspase-3 activation.

Comprehensive and quantitative information of the thermophile proteome is an important source for understanding of the survival mechanism under high growth temperature. Thermoanaerobacter tengcongensis (T. tengcongensis), a typical anaerobic thermophilic eubacterium, was selected to quantitatively evaluate its protein abundance changes in response to four different temperatures. With optimized procedures of isobaric tags for relative and absolute quantitation quantitative proteomics (iTRAQ), such as peptide fractionation with high-pH reverse phase (RP) high performance liquid chromatography (HPLC), tandem MS acquisition mode in LTQ Orbitrap Velos MS, and evaluation of the quantification algorithms, high quality of the quantitative information of the peptides identified were acquired. In total, 1589 unique proteins were identified and defined 251 as the temperature-dependent proteins. Analysis of genomic locations toward the correspondent genes of these temperature-dependent proteins revealed that more than 30% were contiguous units with relevant biological functions, which are likely to form the operon structures in T. tengcongensis. The RNA sequencing (RNA-seq) data further demonstrated that these cluster genes were cotranscribed, and their mRNA abundance changes responding to temperature exhibited the similar trends as the proteomic results, suggesting that the temperature-dependent proteins are highly associated with the correspondent transcription status. Hence, the operon regulation is likely an energy-efficient mode for T. tengcongensis survival. In addition, evaluation to the functions of differential proteomes indicated that the abundance of the proteins participating in sulfur-respiration on the plasma membrane was decreased as the temperature increased, whereas the glycolysis-related protein abundance was increased. The energy supply in T. tengcongensis at high temperature is, therefore, speculated not mainly through the respiration chain reactions.

The launch of the Chromosome-Centric Human Proteome Project provides an opportunity to gain insight into the human proteome. The Chinese Human Chromosome Proteome Consortium has initiated proteomic exploration of protein-encoding genes on human chromosomes 1, 8, and 20. Collaboration within the consortium has generated a comprehensive proteome data set using normal and carcinomatous tissues from human liver, stomach, and colon and 13 cell lines originating in these organs. We identified 12,101 proteins (59.8% coverage against Swiss-Prot human entries) with a protein false discovery rate of less than 1%. On chromosome 1, 1,252 proteins mapping to 1,227 genes, representing 60.9% of Swiss-Prot entries, were identified; however, 805 proteins remain unidentified, suggesting that analysis of more diverse samples using more advanced proteomic technologies is required. Genes encoding the unidentified proteins were concentrated in seven blocks, located at p36, q12-21, and q42-44, partly consistent with correlation of these blocks with cancers of the liver, stomach, and colon. Combined transcriptome, proteome, and cofunctionality analyses confirmed 23 coexpression clusters containing 165 genes. Biological information, including chromosome structure, GC content, and protein coexpression pattern was analyzed using multilayered, circular visualization and tabular visualization. Details of data analysis and updates are available in the Chinese Chromosome-Centric Human Proteome Database ( http://proteomeview.hupo.org.cn/chromosome/ ).

The large scale application of electric vehicles (EVs) will cause great impact on power system, while it also provides a new chance to solve problems of the grid as reducing peak-valley difference. Based on the models of EVs' behavior, this paper considers various factors such as charging methods of EVs, price policies of grid companies and charging modes of grid agents and non-grid agents; then the charging behavior of EVs are divided into four scenarios, and the Monte Carlo method is used to evaluate the impact of different scales of EVs on the daily load curve in Guangzhou. The results indicate that the grid companies should take measures to reduce the burden brought by the large application of EVs; it will lead to a better effect on filling the valley load, with the guidance of the peak and valley pricing policy and maximum load pricing policy or when the grid companies control charging behavior of all EVs directly. (7 pages)