Project description:We have developed a high throughput, next-generation DNA sequencing assay for rapid transcription factor binding site (TFBS) discovery in a genomic context. DNA affinity purification sequencing (DAP-seq), which uses affinity-purified transcription factors (TFs) to capture genomic DNA fragments, was applied to all 1,725 Arabidopsis thaliana TFs. High confidence TFBS motifs for 529 TFs and genome-wide enrichment maps for 349 factors were identified. In total,~ 2.7 million TFBS were identified which predict thousands of TF target genes enriched for known and novel functions.. Comparison of TF-binding using cytosine-methylated and -unmethylated genomic DNA revealed a 2-50 fold inhibition at methylated motifs for ~82% (264) of factors tested while 4.6% (15) showed stronger binding to methylated motifs. Finally, we describe how binding of Arabidopsis and maize Auxin Response Factors (ARFs) at phased motif repeats is highly enriched at ARF target gene promoters and how this architecture may allow for stabilization of dimers/multimers.
Project description:Deciphering the tissue origin of cfDNA can reveal abnormal cell death because of diseases, which has great clinical potential in disease detection and monitoring. Here we present one of the largest comprehensive and high-resolution methylation atlas based on Reduced Representative Bisulfite Sequencing (RRBS) data of 521 noncancer tissue samples spanning 29 major types of human tissues. We systematically identified fragment-level tissue-specific methylation patterns and extensively alidated the methylation signature atlas in independent methylation datasets, orthogonal epigenomic markers, and transcription regulatory elements. Based on the rich tissue methylation atlas, we develop the first supervised tissue deconvolution approach, a deep-learning-powered model, cfSort, for sensitive and accurate tissue deconvolution in cfDNA.
Project description:As 5-15% of higher eukaryotes genes are transcription factors (TFs), the lack of transcription factor binding site (TFBS) information for most factors in most organisms limits the study of gene regulation. Here we describe a next-generation sequencing method, DNA affinity purification (DAP-Seq), an in vitro gDNA/TF interaction assay that produces whole-genome TFBS annotation for any factor from any organism. Like ChIP-Seq, DAP-Seq resolves TFBS as discrete peaks at genomic locations which allows for accurate motif prediction direct assignment of functionally relevant target genes, and shows better overlap with ChIP-Seq peaks than indirect motif assignment approaches. We applied DAP-Seq to a set of 50 transcription factors in eight Arabidopsis thaliana and one Zea Mays families to gain novel biological insight into TFBS architectures, functions, evolution and methylation-sensitivity. Overall, DAP-Seq offers a low-cost high-throughput approach to identify TFBS in native sequence context for any organism complete with all DNA chemical modifications.
Project description:To identify binding sites and nodule SAGs that are directly targeted by NAC094, we used DAP-seq, which allows the capture of the NAC094 regulatory targets at the whole-genome scale. A total of 2,819 binding peaks corresponding to 2,721 genes were identified from two repeats of the DAP-seq experiment.
Project description:In this study, we use DNA affinity purification sequencing to identiy genome-wide binding of LFY transcription factor, a master regulator of flower development in Arabidopsis. We generated two sets of data, one using genomic DNA from plant tissue, thus retain DNA methylation, as probe for DNA affinity purification (DAP-seq dataset), and the other using PCR amplified genomic DNA (without DNA methylation; AmpDAP-seq dataset).
Project description:Kernel development is accompanied by complex gene networks. Expression quantitative trait loci (eQTL) analysis is an efficient way to detect the regulatory elements of genes, especially the trans-eQTLs help to construct the regulatory networks of genes and contribute to a better understanding of the intrinsic mechanisms of biological processes. Till now, the 15 DAP (day after pollination) eQTL has been elucidated in maize kernel, but little is known about the early stage. Here, we conduct eQTL analysis for 5 DAP maize kernel using 318 maize inbred lines. The results will provide insights into the genetic basis of early kernel development.