Read by QxMD icon Read


Yan Zhang, Lin An, Jie Xu, Bo Zhang, W Jim Zheng, Ming Hu, Jijun Tang, Feng Yue
Although Hi-C technology is one of the most popular tools for studying 3D genome organization, due to sequencing cost, the resolution of most Hi-C datasets are coarse and cannot be used to link distal regulatory elements to their target genes. Here we develop HiCPlus, a computational approach based on deep convolutional neural network, to infer high-resolution Hi-C interaction matrices from low-resolution Hi-C data. We demonstrate that HiCPlus can impute interaction matrices highly similar to the original ones, while only using 1/16 of the original sequencing reads...
February 21, 2018: Nature Communications
Karim Labreche, Ben Kinnersley, Giulia Berzero, Anna Luisa Di Stefano, Amithys Rahimian, Ines Detrait, Yannick Marie, Benjamin Grenier-Boley, Khe Hoang-Xuan, Jean-Yves Delattre, Ahmed Idbaih, Richard S Houlston, Marc Sanson
Recent genome-wide association studies of glioma have led to the discovery of single nucleotide polymorphisms (SNPs) at 25 loci influencing risk. Gliomas are heterogeneous, hence to investigate the relationship between risk SNPs and glioma subtype we analysed 1659 tumours profiled for IDH mutation, TERT promoter mutation and 1p/19q co-deletion. These data allowed definition of five molecular subgroups of glioma: triple-positive (IDH mutated, 1p/19q co-deletion, TERT promoter mutated); TERT-IDH (IDH mutated, TERT promoter mutated, 1p/19q-wild-type); IDH-only (IDH mutated, 1p/19q wild-type, TERT promoter wild-type); triple-negative (IDH wild-type, 1p/19q wild-type, TERT promoter wild-type) and TERT-only (TERT promoter mutated, IDH wild-type, 1p/19q wild-type)...
February 19, 2018: Acta Neuropathologica
David Lando, Tim J Stevens, Srinjan Basu, Ernest D Laue
Single-cell chromosome conformation capture approaches are revealing the extent of cell-to-cell variability in the organization and packaging of genomes. These single-cell methods, unlike their multi-cell counterparts, allow straightforward computation of realistic chromosome conformations that may be compared and combined with other, independent, techniques to study 3D structure. Here we discuss how single-cell Hi-C and subsequent 3D genome structure determination allows comparison with data from microscopy...
February 12, 2018: Nucleus
James T Robinson, Douglass Turner, Neva C Durand, Helga Thorvaldsdóttir, Jill P Mesirov, Erez Lieberman Aiden
Contact mapping experiments such as Hi-C explore how genomes fold in 3D. Here, we introduce Juicebox.js, a cloud-based web application for exploring the resulting datasets. Like the original Juicebox application, Juicebox.js allows users to zoom in and out of such datasets using an interface similar to Google Earth. Juicebox.js also has many features designed to facilitate data reproducibility and sharing. Furthermore, Juicebox.js encodes the exact state of the browser in a shareable URL. Creating a public browser for a new Hi-C dataset does not require coding and can be accomplished in under a minute...
February 5, 2018: Cell Systems
Rubina Jibran, Helge Dzierzon, Nahla Bassil, Jill M Bushakra, Patrick P Edger, Shawn Sullivan, Chad E Finn, Michael Dossett, Kelly J Vining, Robert VanBuren, Todd C Mockler, Ivan Liachko, Kevin M Davies, Toshi M Foster, David Chagné
Black raspberry (Rubus occidentalis L.) is a niche fruit crop valued for its flavor and potential health benefits. The improvement of fruit and cane characteristics via molecular breeding technologies has been hindered by the lack of a high-quality reference genome. The recently released draft genome for black raspberry (ORUS 4115-3) lacks assembly of scaffolds to chromosome scale. We used high-throughput chromatin conformation capture (Hi-C) and Proximity-Guided Assembly (PGA) to cluster and order 9650 out of 11,936 contigs of this draft genome assembly into seven pseudo-chromosomes...
2018: Horticulture Research
Yanjian Li, Yi He, Zhengyu Liang, Yang Wang, Fengling Chen, Mohamed Nadhir Djekidel, Guipeng Li, Xu Zhang, Shuqin Xiang, Zejun Wang, Juntao Gao, Michael Q Zhang, Yang Chen
Chromatin conformation plays a key role in regulating gene expression and controlling cell differentiation. However, the whole-genome chromatin conformation changes that occur during leukemia cell differentiation are poorly understood. Here, we characterized the changes in chromatin conformation, histone states, chromatin accessibility, and gene expression using an all-trans retinoic acid (ATRA)-induced HL-60 cell differentiation model. The results showed that the boundaries of topological associated domains (TADs) were stable during differentiation; however, the chromatin conformations within several specific TADs were obviously changed...
February 8, 2018: Cell Death & Disease
Petros Kolovos, Rutger W W Brouwer, Christel E M Kockx, Michael Lesnussa, Nick Kepper, Jessica Zuin, A M Ali Imam, Harmen J G van de Werken, Kerstin S Wendt, Tobias A Knoch, Wilfred F J van IJcken, Frank Grosveld
Chromosome conformation capture (3C) and its derivatives (e.g., 4C, 5C and Hi-C) are used to analyze the 3D organization of genomes. We recently developed targeted chromatin capture (T2C), an inexpensive method for studying the 3D organization of genomes, interactomes and structural changes associated with gene regulation, the cell cycle, and cell survival and development. Here, we present the protocol for T2C based on capture, describing all experimental steps and bio-informatic tools in full detail. T2C offers high resolution, a large dynamic interaction frequency range and a high signal-to-noise ratio...
March 2018: Nature Protocols
Yixiao Gong, Charalampos Lazaris, Theodore Sakellaropoulos, Aurelie Lozano, Prabhanjan Kambadur, Panagiotis Ntziachristos, Iannis Aifantis, Aristotelis Tsirigos
The metazoan genome is compartmentalized in areas of highly interacting chromatin known as topologically associating domains (TADs). TADs are demarcated by boundaries mostly conserved across cell types and even across species. However, a genome-wide characterization of TAD boundary strength in mammals is still lacking. In this study, we first use fused two-dimensional lasso as a machine learning method to improve Hi-C contact matrix reproducibility, and, subsequently, we categorize TAD boundaries based on their insulation score...
February 7, 2018: Nature Communications
Guangxiang Zhu, Wenxuan Deng, Hailin Hu, Rui Ma, Sai Zhang, Jinglin Yang, Jian Peng, Tommy Kaplan, Jianyang Zeng
Decoding the spatial organizations of chromosomes has crucial implications for studying eukaryotic gene regulation. Recently, chromosomal conformation capture based technologies, such as Hi-C, have been widely used to uncover the interaction frequencies of genomic loci in a high-throughput and genome-wide manner and provide new insights into the folding of three-dimensional (3D) genome structure. In this paper, we develop a novel manifold learning based framework, called GEM (Genomic organization reconstructor based on conformational Energy and Manifold learning), to reconstruct the three-dimensional organizations of chromosomes by integrating Hi-C data with biophysical feasibility...
February 2, 2018: Nucleic Acids Research
Kelin Xia
In this paper, we introduce sequence-based multiscale modeling for biomolecular data analysis. We employ spectral clustering method in our modeling and reveal the difference between sequence-based global scale clustering and local scale clustering. Essentially, two types of distances, i.e., Euclidean (or spatial) distance and genomic (or sequential) distance, can be used in data clustering. Clusters from sequence-based global scale models optimize spatial distances, meaning spatially adjacent loci are more likely to be assigned into the same cluster...
2018: PloS One
Enrique Vidal, François le Dily, Javier Quilez, Ralph Stadhouders, Yasmina Cuartero, Thomas Graf, Marc A Marti-Renom, Miguel Beato, Guillaume J Filion
The three-dimensional conformation of genomes is an essential component of their biological activity. The advent of the Hi-C technology enabled an unprecedented progress in our understanding of genome structures. However, Hi-C is subject to systematic biases that can compromise downstream analyses. Several strategies have been proposed to remove those biases, but the issue of abnormal karyotypes received little attention. Many experiments are performed in cancer cell lines, which typically harbor large-scale copy number variations that create visible defects on the raw Hi-C maps...
January 31, 2018: Nucleic Acids Research
Wenxiu Ma, Ferhat Ay, Choli Lee, Gunhan Gulsoy, Xinxian Deng, Savannah Cook, Jennifer Hesson, Christopher Cavanaugh, Carol B Ware, Anton Krumm, Jay Shendure, C Anthony Blau, Christine M Disteche, William S Noble, ZhiJun Duan
The folding and three-dimensional (3D) organization of chromatin in the nucleus critically impacts genome function. The past decade has witnessed rapid advances in genomic tools for delineating 3D genome architecture. Among them, chromosome conformation capture (3C)-based methods such as Hi-C are the most widely used techniques for mapping chromatin interactions. However, traditional Hi-C protocols rely on restriction enzymes (REs) to fragment chromatin and are therefore limited in resolution. We recently developed DNase Hi-C for mapping 3D genome organization, which uses DNase I for chromatin fragmentation...
January 31, 2018: Methods: a Companion to Methods in Enzymology
Johan H Gibcus, Kumiko Samejima, Anton Goloborodko, Itaru Samejima, Natalia Naumova, Johannes Nuebler, Masato T Kanemaki, Linfeng Xie, James R Paulson, William C Earnshaw, Leonid A Mirny, Job Dekker
Mitotic chromosomes fold as compact arrays of chromatin loops. To identify the pathway of mitotic chromosome formation, we combined imaging and Hi-C of synchronous DT40 cell cultures with polymer simulations. We show that in prophase, the interphase organization is rapidly lost in a condensin-dependent manner and arrays of consecutive 60 kb loops are formed. During prometaphase ~80 kb inner loops are nested within ~400 kb outer loops. The loop array acquires a helical arrangement with consecutive loops emanating from a central spiral-staircase condensin scaffold...
January 18, 2018: Science
Qi Wang, Qiu Sun, Daniel M Czajkowsky, Zhifeng Shao
Topologically associating domains (TADs) are fundamental elements of the eukaryotic genomic structure. However, recent studies suggest that the insulating complexes, CTCF/cohesin, present at TAD borders in mammals are absent from those in Drosophila melanogaster, raising the possibility that border elements are not conserved among metazoans. Using in situ Hi-C with sub-kb resolution, here we show that the D. melanogaster genome is almost completely partitioned into >4000 TADs, nearly sevenfold more than previously identified...
January 15, 2018: Nature Communications
Heidi K Norton, Daniel J Emerson, Harvey Huang, Jesi Kim, Katelyn R Titus, Shi Gu, Danielle S Bassett, Jennifer E Phillips-Cremins
Mammalian genomes are folded in a hierarchy of compartments, topologically associating domains (TADs), subTADs and looping interactions. Here, we describe 3DNetMod, a graph theory-based method for sensitive and accurate detection of chromatin domains across length scales in Hi-C data. We identify nested, partially overlapping TADs and subTADs genome wide by optimizing network modularity and varying a single resolution parameter. 3DNetMod can be applied broadly to understand genome reconfiguration in development and disease...
January 15, 2018: Nature Methods
Mel Campbell, Tadashi Watanabe, Kazushi Nakano, Ryan R Davis, Yuanzhi Lyu, Clifford G Tepper, Blythe Durbin-Johnson, Masahiro Fujimuro, Yoshihiro Izumiya
The three-dimensional structure of chromatin organized by genomic loops facilitates RNA polymerase II access to distal promoters. The Kaposi's sarcoma-associated herpesvirus (KSHV) lytic transcriptional program is initiated by a single viral transactivator, K-Rta. Here we report the KSHV genomic structure and its relationship with K-Rta recruitment sites using Capture Hi-C analyses. High-resolution 3D viral genomic maps identify a number of direct physical, long-range, and dynamic genomic interactions. Mutant KSHV chromosomes harboring point mutations in the K-Rta responsive elements (RE) significantly attenuate not only the directly proximate downstream gene, but also distal gene expression in a domain-specific manner...
January 4, 2018: Nature Communications
Changsheng Li, Feng Lin, Dong An, Wenqin Wang, Ruidong Huang
Plant genomes generated by Sanger and Next Generation Sequencing (NGS) have provided insight into species diversity and evolution. However, Sanger sequencing is limited in its applications due to high cost, labor intensity, and low throughput, while NGS reads are too short to resolve abundant repeats and polyploidy, leading to incomplete or ambiguous assemblies. The advent and improvement of long-read sequencing by Third Generation Sequencing (TGS) methods such as PacBio and Nanopore have shown promise in producing high-quality assemblies for complex genomes...
December 28, 2017: Genes
Benjamin Patterson, Yoshiaki Tanaka, In-Hyun Park
Recent advances in stem cell biology have dramatically increased the understanding of molecular and cellular mechanism of pluripotency and cell fate determination. Additionally, pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), arose as essential resources for disease modeling and cellular therapeutics. Despite these advancements, the epigenetic dysregulation in pluripotency such as the imprinting status, and X chromosome dosage compensation, and its consequences on future utility of PSCs yet remain unresolved...
December 2017: Tissue Engineering and Regenerative Medicine
Hui Fan, Pin Lv, Xiangru Huo, Jicheng Wu, Qianfeng Wang, Lu Cheng, Yun Liu, Qiqun Tang, Ling Zhang, Feng Zhang, Xiaoqi Zheng, Hao Wu, Bo Wen
The eukaryotic chromosomes are folded into higher-order conformation to coordinate genome functions. Besides long-range chromatin loops, recent chromosome conformation capture (3C)-based studies indicated the higher level of chromatin structures including compartments and topologically associating domains (TADs), which may serve as units of genome organization and functions. However, the molecular machinery underlying these hierarchically three-dimensional (3D) chromatin architectures remains poorly understood...
December 22, 2017: Genome Research
Xiaobin Zheng, Yixian Zheng
Summary: The genome-wide chromosome conformation capture (Hi-C) has revealed that the eukaryotic genome can be partitioned into A and B compartments that have distinctive chromatin and transcription features. Current Principle Component Analyses (PCA)-based method for the A/B compartment prediction based on Hi-C data requires substantial CPU time and memory. We report the development of a method, CscoreTool, that enables fast and memory-efficient determination of A/B compartments at high resolution even in datasets with low sequencing depth...
December 13, 2017: Bioinformatics
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"