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Song, Q.

Publications and source records attributed to Song, Q..

6 recordsLinked to original sources

An All-to-All Approach to the Identification of Sequence-Specific Readers for Epigenetic DNA Modifications on Cytosine

The authors have withdrawn their manuscript whilst they perform additional experiments to test some of their conclusions further. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.Competing Interest StatementThe authors have declared no competing interest.

systems biology

Prediction of condition-specific regulatory maps in Arabidopsis using integrated genomic data

Recent advances in genomic technologies have generated large-scale protein-DNA interaction data and open chromatic regions for multiple plant species. To predict condition specific gene regulatory networks using these data, we developed the Condition Specific Regulatory network inference engine (ConSReg), which combines heterogeneous genomic data using sparse linear model followed by feature selection and stability selection to select key regulatory genes. Using Arabidopsis as a model system, we constructed maps of gene regulation under more than 50 experimental conditions including abiotic stresses, cell type-specific expression, and stress responses in individual cell types. Our results show that ConSReg accurately predicted gene expressions (average auROC of 0.84) across multiple testing datasets. We found that, (1) including open chromatin information from ATAC-seq data significantly improves the performance of ConSReg across all tested datasets; (2) choice of negative training samples and length of promoter regions are two key factors that affect model performance. We applied ConSReg to Arabidopsis single cell RNA-seq data of two root cell types (endodermis and cortex) and identified five regulators in two root cell types. Four out of the five regulators have additional experimental evidence to support their roles in regulating gene expression in Arabidopsis roots. By comparing regulatory maps in abiotic stress responses and cell type-specific experiments, we revealed that transcription factors that regulate tissue levels abiotic stresses tend to also regulate stress responses in individual cell types in plants.

bioinformatics

The differential distribution of bacteria between cancerous and noncancerous ovarian tissues in situ

The female upper reproductive tract, including the uterus, fallopian tubes and ovaries, is believed to be a sterile environment. With the improvement of bacterial detection, the theory of the sterile female upper reproductive tract has been frequently challenged in recent years. However, thus far, no researchers have used ovaries as study targets. Six women who were diagnosed with ovarian cancer were included in the cancer group, and ten women who were diagnosed with a noncancerous ovarian condition (including three patients with uterine myoma and seven patients with uterine adenomyosis) were included in the control group. Immunohistochemistry staining using an antibacterial lipopolysaccharide (LPS) antibody was used to confirm the presence of bacteria in the ovarian tissues. In addition, 16S rRNA sequencing was used to compare the differences in the bacteria between ovarian cancer tissues and noncancerous ovarian tissues. BugBase and Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) were used to predict the functional composition of the bacteria. Bacterial LPS was present in ovarian cancer tissue and noncancerous ovarian tissue, which implied the presence of bacteria in ovarian tissue. When compared to the noncancerous ovarian bacteria at the phylum level, the cancerous ovarian bacteria were composed of increased Aquificae and Planctomycetes and decreased Crenarchaeota. When predicting metagenomes, gene functions associated with the potentially pathogenic and the oxidative stress-tolerant phenotype were enriched in the ovaries of the cancer group. Forty-six significantly different KEGG pathways existed in the ovarian bacteria of the cancer group compared to that of the control group. Different bacteria compositions were present in cancerous and noncancerous ovarian tissues. Author summaryAbdominal solid viscera have always been believed to be absolutely sterile. With the improvement of bacterial detection, this concept is being challenged. Researchers found some bacteria existed in endometrial diseases, the question of whether the ovaries are sterile is still unclear. Therefore, we assume that the bacteria in ovarian tissue are associated with ovarian cancer. When compared to the noncancerous ovarian bacteria at the phylum level, the cancerous ovarian bacteria were composed of increased Aquificae and Planctomycetes and decreased Crenarchaeota. When predicting metagenomes, gene functions associated with the potentially pathogenic and the oxidative stress-tolerant phenotype were enriched in the ovaries of the cancer group. Forty-six significantly different KEGG pathways existed in the ovarian bacteria of the cancer group compared to that of the control group. Different bacteria compositions were present in cancerous and noncancerous ovarian tissues.

microbiology

Genetic Diversity and Phylogenetic Relationships of Annual and Perennial Glycine Species

We estimated average genetic diversity of two Glycine annual and six perennial species based upon 76 orthologous gene sets and performed phylogenetic analysis, divergence analysis and tests for departure from neutrality of the eight species using 52 orthologous gene sets. In addition, 367 orthologous gene sets were used to estimate the relationships of 11 G. canescens accessions. Among the perennials, G. canescens showed the highest nucleotide diversity and the other perennials except G. tomentella had higher nucleotide diversity than the two annuals. Phylogenetic analysis of the Glycine showed a similar genome grouping with the previous report except G. cyrtoloba and G. stenophita formed a sister clade in the study. Divergence analysis supported the phylogenetic relationships, G. falcata was the most divergent from G. max, followed by G. cyrtoloba, G. syndetika, G. tomentella D3, G. stenophita and G. canescens. Neutrality selection tests within species showed that most genes were subjected to a recent directional selection due to a selective sweep or rapid population expansion. Although most gene sequence had negative and significant Tajimas D, the sequences were homogeneous in the levels of polymorphism and divergence between G. max and other Glycine species based on the HKA test, thus, Glycine perennials may have experienced very similar evolutionary selection as inferred by trans-specific mutation analysis. The greater genetic diversity of most perennial Glycine species and their origins from the warmer and drier climates of Australia suggested the perennials as potential sources of heat and drought resistance that will be of value in the face of climate change.

genetics

A Machine Learning Approach for Long-Term Prognosis of Bladder Cancer based on Clinical and Molecular Features

Improving the consistency and reproducibility of bladder cancer prognoses necessitates the development of accurate, predictive prognostic models. Current methods of determining the prognosis of bladder cancer patients rely on manual decision-making, including factors with high intra- and inter-observer variability, such as tumor grade. To advance the long-term prediction of bladder cancer prognoses, we developed and tested a computational model to predict the 10-year overall survival outcome using population-based bladder cancer data, without considering tumor grade classification. The resulted predictive model demonstrated promising performance using a combination of clinical and molecular features, and was also strongly related to patient overall survival in Cox models. Our study suggests that machine learning methods can provide reliable long-term prognoses for bladder cancer patients, without relying on the less consistent tumor grade. If validated in clinical trials, this automated approach could guide and improve personalized management and treatment for bladder cancer patients.

bioinformatics

Assessment of gibberellin (GA4+7) mediated changes on grain filling, hormonal behaviour and antioxidants in high-density maize (Zea Mays L.)

Dense plant cultivation is an efficient approach to improve the maize production by maximizing the utilization of energy and nutrient. However, dense plant populations may aggravate the abortion rate of young grains and result in fewer number of kernels per ear. Grain filling rate and duration play a decisive role in maize grain yield. Therefore, increasing plant density, consideration of enhancing the grain filling rate and duration of individual maize plant and regulating crop senescence would be the first priority. In this study, we examined the regulatory effects of GA4+7 under two application methods (shank-smearing and silk-smearing). Shank-soaking with GA4+7 at the rate of 0 (CK1), 10 (T1), 60 (T2), and 120 (T3) mg L-1, while silk-smearing at the rate of 0 (CK2), 10 (S1), 60 (S2), and 120 (S3) mg L-1 were used. The results showed that GA4+7 improved the grain filling rate by increasing the content of auxin, gibberellin and zeatin and abscisic acid in grains compared to control plants. In addition, The auxin, gibberellin and zeatin contents in the grains were positively and significantly correlated with the maximum grain weight and the maximum and mean grain-filling rates; the abscisic acid level was positively correlated with the maximum grain weight and the maximum and mean grain-filling rates. Moreover, GA4+7 increased the activities of superoxide dismutases, catalases, peroxidases, and reduced the malondialdehyde content in leaves compared with untreated plants. At the rate of 60 mg L-1, GA4+7 showed the greatest effect for shank-smearing and silk-smearing (T2 and S2), followed by 10 mg L-1 (T1) for shank-smearing and 120 mg L-1 (S3) for silk-smearing. Our results suggest that application of 60 mg L-1 GA4+7 for smearing application could efficiently be used for changed the level of hormones in grains and antioxidant enzymes in ear leaf, would be useful for enhancing grain filling rate and delaying leaves senescence, and resulting in an increasing of maize grain yield.

plant biology