About Our Group

Plant Bioinformatics and Functional Epigenomics Group

Epigenetic modifications of the genome allows for a relatively stable and reversible control of gene expression state, which is essential for organisms to adapt the dynamic developmental and environmental cues.

How do plants know when and where to change the epigenome is still a mystery.

We focus on the mechanism controlling the specificity of different Polycomb Group (PcG) members, with integrative approach combining molecular, genetic and computational tools to address the following questions on global level.

  • 1. Where - the specific target loci of different PcG members
  • 2. When - the dynamic changes of PcG targets during developmental and stress response processes
  • 3. How - the specific cofactor controlling the dynamic recruitment and release of PcGs

Recently Publications

note: *, Co-first author; #, Corresponding author ; Lab members’ name are in bold

  1. Anthony J Covarrubias1, Halil Ibrahim Aksoylar1, Jiujiu Yu1, Nathaniel W Snyder2,3, Andrew J Worth2, Shankar S Iyer4, Jiawei Wang5, Issam Ben-Sahra1, Vanessa Byles1, Tiffany Polynne-Stapornkul1, Erika C Espinosa1, Dudley Lamming6, Brendan D Manning1, Yijing Zhang5, Ian A Blair2, Tiffany Horng1*.(2016) Akt-mTORC1signaling regulates Acly to integrate metabolic input to control of macrophage activation. eLIFE.2016,5: p e11612
    https://elifesciences.org/content/5/e11612 PDF

  2. Zhongfei Li1#, Bin Li1#, Jian Liu2, Zhihao Guo1, Yuhao Liu1, Yan Li3, Wen-Hui Shen1,4, Ying Huang3, Hai Huang2, Yijing Zhang2*and Aiwu Dong1*.(2016) Transcription factors AS1 and AS2 interact withLHP1 to repress KNOX genes in Arabidopsis. Journal of Integrative Plant Biology.DOI: 10.1111/jipb.12485
    http://onlinelibrary.wiley.com/doi/10.1111/jipb.12485/abstract PDF

  3. Wang H*, Liu C*, Cheng J*, Liu J, Zhang L, He C, Shen WH, Jin H#, Xu L#, Zhang Y#. (2016) Arabidopsis flower and embryo developmental genes are repressed in seedlings by different combinations of Polycomb Group Proteins in association with distinct sets of cis-regulatory elements. PLoS Genet.12(1):e1005771. doi: 10.1371/journal.pgen.1005771
    http://www.plosgenetics.org/article/comments/info:doi/10.1371/journal.pgen.1005771 PDF Data Browse

  4. Wang J*, Qi M*, Liu J*, Zhang Y#. (2015) CARMO: A Comprehensive Annotation Platform for Functional Exploration of Rice Multi-Omics Data. Plant J. 83(2): 359-374.
    http://bioinfo.sibs.ac.cn/carmo PDF

  5. Li G*, Liu S*, Wang J, He J, Zhang Y#, Xu L #. (2014) ISWI proteins participate in the genome-wide nucleosome distribution in Arabidopsis. Plant J. 78: 706-714
    http://onlinelibrary.wiley.com/doi/10.1111/tpj.12499/abstract PDF

  6. Zhou P, Zhang Y, Ma Q, Gu F, Day DS, He A, Zhou B, Li J, Stevens SM, Romo D, Pu WT#. (2013) Interrogating translational efficiency and lineage-specific transcriptomes using ribosome affinity purification. Proc. Natl. Acad. Sci. U S A. 110: 15395-15400
    http://www.pnas.org/content/110/38/15395.long PDF

  7. Zhang G*, Zhang Y*, Su Z#. (2012) CYPSI: a structure-based interface for cytochrome P450s and ligands in Arabidopsis thaliana. BMC Bioinformatics. 13: 332
    http://www.biomedcentral.com/1471-2105/13/332 PDF

  8. Conforto TL, Zhang Y, Sherman J, Waxman DJ#. (2012) Impact of CUX2 on the Female Mouse Liver Transcriptome: Activation of Female-Biased Genes and Repression of Male-Biased Genes. Mol. Cell. Biol. 32: 4611-4627
    http://mcb.asm.org/content/32/22/4611.long PDF

  9. Shao Z*, Zhang Y*, Yuan GC, Orkin SH, Waxman DJ#. (2012) MAnorm: a robust model for quantitative comparison of ChIP-Seq data sets. Genome Biology. 13: R16
    http://genomebiology.com/content/13/3/R16 PDF

  10. Zhang Y, Laz EV, Waxman DJ#. (2011) Dynamic, Sex-Differential STAT5 and BCL6 Binding to Sex-Biased, Growth Hormone-Regulated Genes in Adult Mouse Liver. Mol. Cell. Biol. 32: 880-896
    http://mcb.asm.org/content/32/4/880.lon PDF

  11. Zhang Y, Klein K, Sugathan A, Nassery N, Dombkowski A, Zanger UM, Waxman DJ#. (2011) Transcriptional Profiling of Human Liver Identifies Sex- with Polygenic Biased Genes Associated Dyslipidemia and Coronary Artery Disease. PLos One. 6: e23506
    http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0023506 PDF

  12. Bagchi G*, Zhang Y*, Stanley KA, Waxman DJ#. (2011) Complex modulation of androgen responsive gene expression by methoxyacetic acid. Reprod. Biol. Endocrinol. 9: 42
    http://www.rbej.com/content/9/1/42g PDF

  13. Dixit E, Boulant S, Zhang Y, Lee AS, Odendall C, Shum B, Hacohen N, Chen ZJ, Whelan SP, Fransen M, Nibert ML, Superti-Furga G, Kagan JC#. (2010) Peroxisomes are signaling platforms for antiviral innate immunity. Cell. 141: 668-681
    http://www.sciencedirect.com/science/article/pii/S0092867410004356 PDF

  14. Bagchi G, Zhang Y, Waxman DJ#. (2010) Impact of methoxyacetic acid on mouse Leydig cell gene expression. Reprod. Biol. Endocrinol. 8: 65
    http://www.rbej.com/content/8/1/65 PDF

  15. Xue Y*, Zhang Y*, Yang Y*, Li Q, Cheng Z, Dickinson HG#. (2009) Genetic features of a pollen-part mutation suggest an inhibitory role for the Antirrhinum pollen self-incompatibility determinant. Plant Mol. Biol. 70: 499-509
    http://link.springer.com/article/10.1007%2Fs11103-009-9487-9 PDF

  16. Zhang Y, Zhao Z, and Xue Y#. (2009) Roles of Proteolysis in Plant Self-Incompatibility. Annu. Rev. Plant Biol. 60: 21-42
    http://www.annualreviews.org/doi/full/10.1146/annurev.arplant.043008.092108 PDF

  17. Zhang Y and Xue Y#. “Molecular Biology of S-RNase-based Self-Incompatibility” in Book “Self-Incompatibility in Flowering Plants”.(2008) Berlin- Heidelberg-New York: Springer-Verlag, p193-215
    http://link.springer.com/chapter/10.1007/978-3-540-68486-2_9 PDF

People


Software and Databases

CARMO: Comprehensive Annotation of Rice Multi-Omics

CARMO is a web-based platform providing comprehensive annotations for multi-omics data, including transcriptomic data sets, epi-genomic modification sites, SNPs from genome re-sequencing, and the large gene lists derived from these omics studies. Well-organized results, as well as multiple tools for interactive visualization, are available through a user-friendly web interface.

The power of CARMO lies in the comprehensive collection and integration of information from both multi-omics data and diverse functional evidence of rice, which was further curated into gene sets and higher level gene modules. In this way, the high-throughput data can easily be compared across studies and platforms, and notably, integration of multiple types of evidence provides biological interpretation from the level of modules with high confidence. Examples in the manuscripts demonstrated that CARMO not only reproduced reported evidence, but also proposed novel functional insights for further experimental exploration.

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MAnorm: ChIP-Seq data quantitative comparison

ChIP-Seq is widely used to characterize genome-wide binding patterns of transcription factors and other chromatin-associated proteins. Although comparison of ChIP-Seq data sets is critical for understanding cell type-dependent and cell state-specific binding, and thus the study of cell-specific gene regulation, few quantitative approaches have been developed. Here, we present a simple and effective method, MAnorm, for quantitative comparison of ChIP-Seq data sets describing transcription factor binding sites and epigenetic modifications. The quantitative binding differences inferred by MAnorm showed strong correlation with both the changes in expression of target genes and the binding of cell type-specific regulators.

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Motif-Scan: scan genomic regions for target of given motifs and perform enrichment analysis

(Under Constuction) With the accumulation of ChIP-seq data across different cell types, an effective and accurate method are essential to unravel the relationship between regulator binding and epigenetic modifications in different cell types. We present an integrative computational toolkit, MAmotif, to infer cell type specific regulators.

Based on a hypotheses that the regions with higher epigenetic changes are more likely to be directly targeted by key cell type specific regulators, we combine MAnorm’s quantitative comparison information of 2 cell types and transcription factor binding sites information to infer cell type specific regulators. Here MAnorm is a model for quantitative comparison of ChIP-seq data between 2 cell types. While TFBS are detected from the epigenetic change regions by our newly developed motif scanning package.

Our motif scan algorithm is a probabilistic model based on position weight matrix (PWM): the score of motif A is calculated as the ratio of A’s probability of occurrence on the target sequence and its probability of occurrence on the genome background. The target sequence can finally be defined as the motif A target sequence when the score is beyond the score threshold, which is from the distribution of motif A scores calculated on the whole genome sequence. When the epigenetic modification changes and TFBS information are prepared, several statistical tests and clustering methods are applied to determine the linkage between epigenetic modification changes and the motif binding affinity in specific cell type.

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CYPSI: P450 protein structure database

The CYP Structure Interface (CYPSI) is a platform for CYP studies. CYPSI integrated the 3D structures for 266 A. thaliana CYPs predicted by three TBM methods: BMCD, which we developed specifically for CYP TBM; and two well-known web-servers, MUSTER and I-TASSER. After careful template selection and optimization, the models built by BMCD were accurate enough for practical application, which we demonstrated using a docking example aimed at searching for the CYPs responsible for ABA 8′-hydroxylation. CYPSI also provides extensive resources for A. thaliana CYP structure and function studies, including 400 PDB entries for solved CYPs, 48 metabolic pathways associated with A. thaliana CYPs, 232 reported CYP ligands and 18 A. thaliana CYPs docked with ligands (61 complexes in total). In addition, CYPSI also includes the ability to search for similar sequences and chemicals.

CYPSI provides comprehensive structure and function information for A. thaliana CYPs, which should facilitate investigations into the interactions between CYPs and their substrates. CYPSI has a user-friendly interface, which is available at http://bioinfo.cau.edu.cn/CYPSI.

Go to CYPSI >>>