Life Sciences Commons^™

Genetic Drivers Of Heterogeneity In Type 2 Diabetes Pathophysiology, Ken Suzuki, Konstantinos Hatzikotoulas, Lorraine Southam, Henry J Taylor, Xianyong Yin, Kim M Lorenz, Ravi Mandla, Alicia Huerta-Chagoya, Giorgio E M Melloni, Stavroula Kanoni, Nigel W Rayner, Ozvan Bocher, Ana Luiza Arruda, Kyuto Sonehara, Shinichi Namba, Simon S K Lee, Michael H Preuss, Lauren E Petty, Philip Schroeder, Brett Vanderwerff, Mart Kals, Fiona Bragg, Kuang Lin, Xiuqing Guo, Weihua Zhang, Jie Yao, Young Jin Kim, Mariaelisa Graff, Fumihiko Takeuchi, Jana Nano, Amel Lamri, Masahiro Nakatochi, Sanghoon Moon, Robert A Scott, James P Cook, Jung-Jin Lee, Ian Pan, Daniel Taliun, Esteban J Parra, Jin-Fang Chai, Lawrence F Bielak, Yasuharu Tabara, Yang Hai, Gudmar Thorleifsson, Niels Grarup, Tamar Sofer, Matthias Wuttke, Chloé Sarnowski, Christian Gieger, Darryl Nousome, Stella Trompet, Soo-Heon Kwak, Jirong Long, Meng Sun, Lin Tong, Wei-Min Chen, Suraj S Nongmaithem, Raymond Noordam, Victor J Y Lim, Claudia H T Tam, Yoonjung Yoonie Joo, Chien-Hsiun Chen, Laura M Raffield, Bram Peter Prins, Aude Nicolas, Lisa R Yanek, Guanjie Chen, Jennifer A Brody, Edmond Kabagambe, Ping An, Anny H Xiang, Hyeok Sun Choi, Brian E Cade, Jingyi Tan, K Alaine Broadaway, Alice Williamson, Zoha Kamali, Jinrui Cui, Manonanthini Thangam, Linda S Adair, Adebowale Adeyemo, Carlos A Aguilar-Salinas, Tarunveer S Ahluwalia, Sonia S Anand, Alain Bertoni, Jette Bork-Jensen, Ivan Brandslund, Thomas A Buchanan, Charles F Burant, Adam S Butterworth, Mickaël Canouil, Juliana C N Chan, Li-Ching Chang, Miao-Li Chee, Ji Chen, Shyh-Huei Chen, Yuan-Tsong Chen, Zhengming Chen, Lee-Ming Chuang, Mary Cushman, John Danesh, Swapan K Das, H Janaka De Silva, George Dedoussis, Latchezar Dimitrov, Ayo P Doumatey, Shufa Du, Qing Duan, Kai-Uwe Eckardt, Leslie S Emery, Daniel S Evans, Michele K Evans, Krista Fischer, James S Floyd, Ian Ford, Oscar H Franco, Timothy M Frayling, Barry I Freedman, Pauline Genter, Hertzel C Gerstein, Vilmantas Giedraitis, Clicerio González-Villalpando, Maria Elena González-Villalpando, Penny Gordon-Larsen, Myron Gross, Lindsay A Guare, Sophie Hackinger, Liisa Hakaste, Sohee Han, Andrew T Hattersley, Christian Herder, Momoko Horikoshi, Annie-Green Howard, Willa Hsueh, Mengna Huang, Wei Huang, Yi-Jen Hung, Mi Yeong Hwang, Chii-Min Hwu, Sahoko Ichihara, Mohammad Arfan Ikram, Martin Ingelsson, Md Tariqul Islam, Masato Isono, Hye-Mi Jang, Farzana Jasmine, Guozhi Jiang, Jost B Jonas, Torben Jørgensen, Frederick K Kamanu, Fouad R Kandeel, Anuradhani Kasturiratne, Tomohiro Katsuya, Varinderpal Kaur, Takahisa Kawaguchi, Jacob M Keaton, Abel N Kho, Chiea-Chuen Khor, Muhammad G Kibriya, Duk-Hwan Kim, Florian Kronenberg, Johanna Kuusisto, Kristi Läll, Leslie A Lange, Kyung Min Lee, Myung-Shik Lee, Nanette R Lee, Aaron Leong, Liming Li, Yun Li, Ruifang Li-Gao, Symen Ligthart, Cecilia M Lindgren, Allan Linneberg, Ching-Ti Liu, Jianjun Liu, Adam E Locke, Tin Louie, Jian'an Luan, Andrea O Luk, Xi Luo, Jun Lv, Julie A Lynch, Valeriya Lyssenko, Shiro Maeda, Vasiliki Mamakou, Sohail Rafik Mansuri, Koichi Matsuda, Thomas Meitinger, Olle Melander, Andres Metspalu, Huan Mo, Andrew D Morris, Filipe A Moura, Jerry L Nadler, Michael A Nalls, Uma Nayak, Ioanna Ntalla, Yukinori Okada, Lorena Orozco, Sanjay R Patel, Snehal Patil, Pei Pei, Mark A Pereira, Annette Peters, Fraser J Pirie, Hannah G Polikowsky, Bianca Porneala, Gauri Prasad, Laura J Rasmussen-Torvik, Alexander P Reiner, Michael Roden, Rebecca Rohde, Katheryn Roll, Charumathi Sabanayagam, Kevin Sandow, Alagu Sankareswaran, Naveed Sattar, Sebastian Schönherr, Mohammad Shahriar, Botong Shen, Jinxiu Shi, Dong Mun Shin, Nobuhiro Shojima, Jennifer A Smith, Wing Yee So, Alena Stančáková, Valgerdur Steinthorsdottir, Adrienne M Stilp, Konstantin Strauch, Kent D Taylor, Barbara Thorand, Unnur Thorsteinsdottir, Brian Tomlinson, Tam C Tran, Fuu-Jen Tsai, Jaakko Tuomilehto, Teresa Tusie-Luna, Miriam S Udler, Adan Valladares-Salgado, Rob M Van Dam, Jan B Van Klinken, Rohit Varma, Niels Wacher-Rodarte, Eleanor Wheeler, Ananda R Wickremasinghe, Ko Willems Van Dijk, Daniel R Witte, Chittaranjan S Yajnik, Ken Yamamoto, Kenichi Yamamoto, Kyungheon Yoon, Canqing Yu, Jian-Min Yuan, Salim Yusuf, Matthew Zawistowski, Liang Zhang, Wei Zheng, Leslie J Raffel, Michiya Igase, Eli Ipp, Susan Redline, Yoon Shin Cho, Lars Lind, Michael A Province, Myriam Fornage, Craig L Hanis, Erik Ingelsson, Alan B Zonderman, Bruce M Psaty, Ya-Xing Wang, Charles N Rotimi, Diane M Becker, Fumihiko Matsuda, Yongmei Liu, Mitsuhiro Yokota, Sharon L R Kardia, Patricia A Peyser, James S Pankow, James C Engert, Amélie Bonnefond, Philippe Froguel, James G Wilson, Wayne H H Sheu, Jer-Yuarn Wu, M Geoffrey Hayes, Ronald C W Ma, Tien-Yin Wong, Dennis O Mook-Kanamori, Tiinamaija Tuomi, Giriraj R Chandak, Francis S Collins, Dwaipayan Bharadwaj, Guillaume Paré, Michèle M Sale, Habibul Ahsan, Ayesha A Motala, Xiao-Ou Shu, Kyong-Soo Park, J Wouter Jukema, Miguel Cruz, Yii-Der Ida Chen, Stephen S Rich, Roberta Mckean-Cowdin, Harald Grallert, Ching-Yu Cheng, Mohsen Ghanbari, E-Shyong Tai, Josee Dupuis, Norihiro Kato, Markku Laakso, Anna Köttgen, Woon-Puay Koh, Donald W Bowden, Colin N A Palmer, Jaspal S Kooner, Charles Kooperberg, Simin Liu, Kari E North, Danish Saleheen, Torben Hansen, Oluf Pedersen, Nicholas J Wareham, Juyoung Lee, Bong-Jo Kim, Iona Y Millwood, Robin G Walters, Kari Stefansson, Emma Ahlqvist, Mark O Goodarzi, Karen L Mohlke, Claudia Langenberg, Christopher A Haiman, Ruth J F Loos, Jose C Florez, Daniel J Rader, Marylyn D Ritchie, Sebastian Zöllner, Reedik Mägi, Nicholas A Marston, Christian T Ruff, David A Van Heel, Sarah Finer, Joshua C Denny, Toshimasa Yamauchi, Takashi Kadowaki, John C Chambers, Maggie C Y Ng, Xueling Sim, Jennifer E Below, Philip S Tsao, Kyong-Mi Chang, Mark I Mccarthy, James B Meigs, Anubha Mahajan, Cassandra N Spracklen, Josep M Mercader, Michael Boehnke, Jerome I Rotter, Marijana Vujkovic, Benjamin F Voight, Andrew P Morris, Eleftheria Zeggini

Journal Articles

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.

Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker

Department of Biochemistry and Molecular Biology Faculty Papers

Fibrosis, or excessive scarring, is characterized by the emergence of alpha-smooth muscle actin (αSMA)-expressing myofibroblasts and the excessive accumulation of fibrotic extracellular matrix (ECM). Currently, there is a lack of effective treatment options for fibrosis, highlighting an unmet need to identify new therapeutic targets. The acquisition of a fibrotic phenotype is associated with changes in chromatin structure, a key determinant of gene transcription activation and repression. The major repressive histone mark, H3K27me3, has been linked to dynamic changes in gene expression in fibrosis through alterations in chromatin structure. H3K27-specific homologous histone methylase (HMT) enzymes, Enhancer of zeste 1 and 2 …

Post-Embryonic Phase Transitions Mediated By Polycomb Repressive Complexes In Plants, Valerie Hinsch, Samuel Adkins, Darren Manuela, Mingli Xu

Faculty Publications

Correct timing of developmental phase transitions is critical for the survival and fitness of plants. Developmental phase transitions in plants are partially promoted by controlling relevant genes into active or repressive status. Polycomb Repressive Complex1 (PRC1) and PRC2, originally identified in Drosophila, are essential in initiating and/or maintaining genes in repressive status to mediate developmental phase transitions. Our review summarizes mechanisms in which the embryo-to-seedling transition, the juvenile-to-adult transition, and vegetative-to-reproductive transition in plants are mediated by PRC1 and PRC2, and suggests that PRC1 could act either before or after PRC2, or that they could function independently of each other. …

Super-Resolution Visualization Of Chromatin Loop Folding In Human Lymphoblastoid Cells Using Interferometric Photoactivated Localization Microscopy., Zofia Parteka-Tojek, Jacqueline Jufen Zhu, Byoungkoo Lee, Karolina Jodkowska, Ping Wang, Jesse Aaron, Teng-Leong Chew, Krzysztof Banecki, Dariusz Plewczynski, Yijun Ruan

Faculty Research 2022

The three-dimensional (3D) genome structure plays a fundamental role in gene regulation and cellular functions. Recent studies in 3D genomics inferred the very basic functional chromatin folding structures known as chromatin loops, the long-range chromatin interactions that are mediated by protein factors and dynamically extruded by cohesin. We combined the use of FISH staining of a very short (33 kb) chromatin fragment, interferometric photoactivated localization microscopy (iPALM), and traveling salesman problem-based heuristic loop reconstruction algorithm from an image of the one of the strongest CTCF-mediated chromatin loops in human lymphoblastoid cells. In total, we have generated thirteen good quality images …

Crispr-Mediated Multiplexed Live Cell Imaging Of Nonrepetitive Genomic Loci With One Guide Rna Per Locus., Patricia A Clow, Menghan Du, Nathaniel L. Jillette, Aziz Taghbalout, Jacqueline J Zhu, Albert Cheng

Faculty Research 2022

Three-dimensional (3D) structures of the genome are dynamic, heterogeneous and functionally important. Live cell imaging has become the leading method for chromatin dynamics tracking. However, existing CRISPR- and TALE-based genomic labeling techniques have been hampered by laborious protocols and are ineffective in labeling non-repetitive sequences. Here, we report a versatile CRISPR/Casilio-based imaging method that allows for a nonrepetitive genomic locus to be labeled using one guide RNA. We construct Casilio dual-color probes to visualize the dynamic interactions of DNA elements in single live cells in the presence or absence of the cohesin subunit RAD21. Using a three-color palette, we track …

Oligomerization Of Mutant P53 R273h Is Not Required For Gain-Of-Function Chromatin Associated Activities, George K. Annor, Nour Elshabassy, Devon Lundine, Don-Gerard Conde, Gu Xiao, Viola Ellison, Jill Bargonetti

Publications and Research

The TP53 gene is often mutated in cancer, with missense mutations found in the central DNA binding domain, and less often in the C-terminal oligomerization domain (OD). These types of mutations are found in patients with the rare inherited cancer predisposition disorder called Li-Fraumeni syndrome. We previously found that mutant p53 (mtp53) R273H associates with replicating DNA and promotes the chromatin association of replication-associated proteins mini-chromosome maintenance 2 (MCM2), and poly ADP-ribose polymerase 1(PARP1). Herein, we created dual mutants in order to test if the oligomerization state of mtp53 R273H played a role in chromatin binding oncogenic gain-of-function (GOF) activities. …

Functional Characterization Of T2d-Associated Snp Effects On Baseline And Er Stress-Responsive Β Cell Transcriptional Activation., Shubham Khetan, Susan Kales, Romy Kursawe, Alexandria Jillette, Jacob C Ulirsch, Steven K Reilly, Duygu Ucar, Ryan Tewhey, Michael L. Stitzel

Faculty Research 2021

Genome-wide association studies (GWAS) have linked single nucleotide polymorphisms (SNPs) at >250 loci in the human genome to type 2 diabetes (T2D) risk. For each locus, identifying the functional variant(s) among multiple SNPs in high linkage disequilibrium is critical to understand molecular mechanisms underlying T2D genetic risk. Using massively parallel reporter assays (MPRA), we test the cis-regulatory effects of SNPs associated with T2D and altered in vivo islet chromatin accessibility in MIN6 β cells under steady state and pathophysiologic endoplasmic reticulum (ER) stress conditions. We identify 1,982/6,621 (29.9%) SNP-containing elements that activate transcription in MIN6 and 879 SNP alleles that …

In Situ Chromatin Interaction Analysis Using Paired-End Tag Sequencing., Ping Wang, Yuliang Feng, Kun Zhu, Haoxi Chai, Ya-Ting Chang, Xiaofei Yang, Xiyuan Liu, Chen Shen, Eva Gega, Byoungkoo Lee, Minji Kim, Xiaoan Ruan, Yijun Ruan

Faculty Research 2021

Chromatin Interaction Analysis Using Paired-End Tag Sequencing (ChIA-PET) is an established method to map protein-mediated chromatin interactions. A limitation, however, is that it requires a hundred million cells per experiment, which hampers its broad application in biomedical research, particularly in studies in which it is impractical to obtain a large number of cells from rare samples. To reduce the required input cell number while retaining high data quality, we developed an in situ ChIA-PET protocol, which requires as few as 1 million cells. Here, we describe detailed step-by-step procedures for performing in situ ChIA-PET from cultured cells, including both an …

Successful Atac-Seq From Snap-Frozen Equine Tissues, Sichong Peng, Rebecca Bellone, Jessica L. Petersen, Theodore S. Kalbfleisch, Carrie J. Finno

Veterinary Science Faculty Publications

An assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) has become an increasingly popular method to assess genome-wide chromatin accessibility in isolated nuclei from fresh tissues. However, many biobanks contain only snap-frozen tissue samples. While ATAC-seq has been applied to frozen brain tissues in human, its applicability in a wide variety of tissues in horse remains unclear. The Functional Annotation of Animal Genome (FAANG) project is an international collaboration aimed to provide high quality functional annotation of animal genomes. The equine FAANG initiative has generated a biobank of over 80 tissues from two reference female animals and experiments to begin …

Successful Atac-Seq From Snap-Frozen Equine Tissues, Sichong Peng, Rebecca Bellone, Jessica Lynn Petersen, Theodore S. Kalbfleisch, Carrie J. Finno

Department of Animal Science: Faculty Publications

An assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) has become an increasingly popular method to assess genome-wide chromatin accessibility in isolated nuclei from fresh tissues. However, many biobanks contain only snap-frozen tissue samples. While ATAC-seq has been applied to frozen brain tissues in human, its applicability in a wide variety of tissues in horse remains unclear. The Functional Annotation of Animal Genome (FAANG) project is an international collaboration aimed to provide high quality functional annotation of animal genomes. The equine FAANG initiative has generated a biobank of over 80 tissues from two reference female animals and experiments to begin …

Deciphering Hierarchical Organization Of Topologically Associated Domains Through Change-Point Testing., Haipeng Xing, Yingru Wu, Michael Q Zhang, Yong Chen

Faculty Scholarship for the College of Science & Mathematics

BACKGROUND: The nucleus of eukaryotic cells spatially packages chromosomes into a hierarchical and distinct segregation that plays critical roles in maintaining transcription regulation. High-throughput methods of chromosome conformation capture, such as Hi-C, have revealed topologically associating domains (TADs) that are defined by biased chromatin interactions within them.

RESULTS: We introduce a novel method, HiCKey, to decipher hierarchical TAD structures in Hi-C data and compare them across samples. We first derive a generalized likelihood-ratio (GLR) test for detecting change-points in an interaction matrix that follows a negative binomial distribution or general mixture distribution. We then employ several optimal search strategies to …

“Adopt-A-Tissue” Initiative Advances Efforts To Identify Tissue-Specific Histone Marks In The Mare, N. B. Kingsley, Natasha A. Hamilton, Gabriella Lindgren, Ludovic Orlando, Ernest Bailey, Samantha Brooks, Molly Mccue, Theodore S. Kalbfleisch, James N. Macleod, Jessica L. Petersen, Carrie J. Finno, Rebecca R. Bellone

Maxwell H. Gluck Equine Research Center Faculty Publications

No abstract provided.

Contribution Of Advanced Fluorescence Nano Microscopy Towards Revealing Mitotic Chromosome Structure, S W. Botchway, Safana Farooq, A Sajid, I K. Robinson, Mohammed Yousuf

Centre for Regenerative Medicine & Stem Cell Research

The organization of chromatin into higher-order structures and its condensation process represent one of the key challenges in structural biology. This is important for elucidating several disease states. To address this long-standing problem, development of advanced imaging methods has played an essential role in providing understanding into mitotic chromosome structure and compaction. Amongst these are two fast evolving fluorescence imaging technologies, specifically fluorescence lifetime imaging (FLIM) and super-resolution microscopy (SRM). FLIM in particular has been lacking in the application of chromosome research while SRM has been successfully applied although not widely. Both these techniques are capable of providing fluorescence imaging …

“Adopt-A-Tissue” Initiative Advances Efforts To Identify Tissue-Specific Histone Marks In The Mare, N B. Kingsley, Natasha A. Hamilton, Gabriella Lindgren, Ludovic Orlando, Ernie Bailey, Samantha Brooks, Molly Mccue, T S. Kalbfleisch, James N. Macleod, Jessica L. Petersen, Carrie J. Finno, Rebecca R. Bellone

Department of Animal Science: Faculty Publications

No abstract provided.

Multiplexed Capture Of Spatial Configuration And Temporal Dynamics Of Locus-Specific 3d Chromatin By Biotinylated Dcas9., Xin Liu, Yong Chen, Yuannyu Zhang, Yuxuan Liu, Nan Liu, Giovanni A Botten, Hui Cao, Stuart H Orkin, Michael Q Zhang, Jian Xu

Faculty Scholarship for the College of Science & Mathematics

The spatiotemporal control of 3D genome is fundamental for gene regulation, yet it remains challenging to profile high-resolution chromatin structure at cis-regulatory elements (CREs). Using C-terminally biotinylated dCas9, endogenous biotin ligases, and pooled sgRNAs, we describe the dCas9-based CAPTURE method for multiplexed analysis of locus-specific chromatin interactions. The redesigned system allows for quantitative analysis of the spatial configuration of a few to hundreds of enhancers or promoters in a single experiment, enabling comparisons across CREs within and between gene clusters. Multiplexed analyses of the spatiotemporal configuration of erythroid super-enhancers and promoter-centric interactions reveal organizational principles of genome structure and function.

Use Of 3d Imaging For Providing Insights Into High-Order Structure Of Mitotic Chromosomes, Mohammad Yusuf, Kohei Kaneyoshi, Kiichi Fukui, Ian Robinson

Centre for Regenerative Medicine & Stem Cell Research

The high-order structure of metaphase chromosomes remains still under investigation, especially the 30-nm structure that is still controversial. Advanced 3D imaging has provided useful information for our understanding of this detailed structure. It is evident that new technologies together with improved sample preparations and image analyses should be adequately combined. This mini review highlights 3D imaging used for chromosome analysis so far with future imaging directions also highlighted.

Coupling Of Parp1-Mediated Chromatin Structural Changes To Transcriptional Rna Polymerase Ii Elongation And Cotranscriptional Splicing, Elena A. Matveeva, Qamar M. H. Al-Tinawi, Eric C. Rouchka, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Background: Recently, we showed that PARP1 is involved in cotranscriptional splicing, possibly by bridging chromatin to RNA and recruiting splicing factors. It also can influence alternative splicing decisions through the regulation of RNAPII elongation. In this study, we investigated the effect of PARP1-mediated chromatin changes on RNAPII movement, during transcription and alternative splicing.

Results: We show that RNAPII pauses at PARP1–chromatin structures within the gene body. Knockdown of PARP1 abolishes this RNAPII pausing, suggesting that PARP1 may regulate RNAPII elongation. Additionally, PARP1 alters nucleosome deposition and histone post-translational modifications at specific exon–intron boundaries, thereby affecting RNAPII movement. Lastly, genome-wide analyses …

Transcription Factor Binding Site Clusters Identify Target Genes With Similar Tissue-Wide Expression And Buffer Against Mutations., Peter Rogan, Ruipeng Lu

Biochemistry Publications

Background: The distribution and composition of cis-regulatory modules composed of transcription factor (TF) binding site (TFBS) clusters in promoters substantially determine gene expression patterns and TF targets. TF knockdown experiments have revealed that TF binding profiles and gene expression levels are correlated. We use TFBS features within accessible promoter intervals to predict genes with similar tissue-wide expression patterns and TF targets using Machine Learning (ML). Methods: Bray-Curtis Similarity was used to identify genes with correlated expression patterns across 53 tissues. TF targets from knockdown experiments were also analyzed by this approach to set up the ML framework. TFBSs were …

Functional Analysis Of The Replication Fork Proteome Identifies Bet Proteins As Pcna Regulators, Sarah R. Wessel, Kareem N. Mohni, Jessica W. Luzwick, Huzefa Dungrawala, David Cortez

Molecular Biosciences Faculty Publications

Identifying proteins that function at replication forks is essential to understanding DNA replication, chromatin assembly, and replication-coupled DNA repair mechanisms. Combining quantitative mass spectrometry in multiple cell types with stringent statistical cutoffs, we generated a high-confidence catalog of 593 proteins that are enriched at replication forks and nascent chromatin. Loss-of-function genetic analyses indicate that 85% yield phenotypes that are consistent with activities in DNA and chromatin replication or already have described functions in these processes. We illustrate the value of this resource by identifying activities of the BET family proteins BRD2, BRD3, and BRD4 in controlling DNA replication. These proteins …

Heritable Sperm Chromatin Epigenetics: A Break To Remember, Ralph G. Meyer, Chelsea C. Ketchum, Mirella L. Meyer-Ficca

UAES Publications

Sperm chromatin not only has a unique structure to condense and protect the paternal DNA in transit, but also provides epigenetic information that supports embryonic development. Most of the unique sperm nuclear architecture is formed during the sweeping postmeiotic chromatin remodeling events in spermiogenesis, where the majority of nucleosomes are removed and replaced by protamines. The remaining histones and other chromatin proteins are located in structurally and transcriptionally relevant positions in the genome and carry diverse post-translational modifications relevant to the control of embryonic gene expression. How such postmeiotic chromatin-based programming of sperm epigenetic information proceeds, and how susceptible the …

Gene 33/Mig6 Regulates Apoptosis And The Dna Damage Response Through Independent Mechanisms, Cen Li, Soyoung Park, Leonard M. Eisenberg, Hong Zhao, Zbigniew Darzynkiewicz, Dazhong Xu

NYMC Faculty Posters

Gene 33 (Mig6, ERRFI1) is an inducible adaptor/scaffold protein whose expression can be induced by both stress and mitogenic signals. It contains multiple domains for protein-protein interaction and is involved in a broad spectrum of cellular functions. Gene 33 promotes apoptosis in a cell type-dependent manner. A recent study has linked Gene 33 to the DNA damage response (DDR) induced by hexavalent chromium [Cr(VI)]. Here we show that Gene 33 induces apoptosis via both c-Abl/p73 and EGFR/AKT-dependent pathways in lung epithelial and lung carcinoma cells. Ectopic expression of Gene 33 also triggers DDR in an ATM-dependent fashion and through pathways …

Epigenomic Reprogramming In Inorganic Arsenic-Mediated Gene Expression Patterns During Carcinogenesis, Meredith Eckstein, Rebekah Eleazer, Matthew Rea, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Arsenic is a ubiquitous metalloid that is not mutagenic but is carcinogenic. The mechanism(s) by which arsenic causes cancer remain unknown. To date, several mechanisms have been proposed, including the arsenic-induced generation of reactive oxygen species (ROS). However, it is also becoming evident that inorganic arsenic (iAs) may exert its carcinogenic effects by changing the epigenome, and thereby modifying chromatin structure and dynamics. These epigenetic changes alter the accessibility of gene regulatory factors to DNA, resulting in specific changes in gene expression both at the levels of transcription initiation and gene splicing. In this review, we discuss recent literature reports …

A Novel Rrm3 Function In Restricting Dna Replication Via An Orc5-Binding Domain Is Genetically Separable From Rrm3 Function As An Atpase/Helicase In Facilitating Fork Progression, Salahuddin Syed, Claus Desler, Lene J Rasmussen, Kristina H Schmidt

Molecular Biosciences Faculty Publications

In response to replication stress cells activate the intra-S checkpoint, induce DNA repair pathways, increase nucleotide levels, and inhibit origin firing. Here, we report that Rrm3 associates with a subset of replication origins and controls DNA synthesis during replication stress. The N-terminal domain required for control of DNA synthesis maps to residues 186-212 that are also critical for binding Orc5 of the origin recognition complex. Deletion of this domain is lethal to cells lacking the replication checkpoint mediator Mrc1 and leads to mutations upon exposure to the replication stressor hydroxyurea. This novel Rrm3 function is independent of its established role …

Cellular And Molecular Features Of Developmentally Programmed Genome Rearrangement In A Vertebrate (Sea Lamprey: Petromyzon Marinus), Vladimir A. Timoshevskiy, Joseph R. Herdy, Melissa C. Keinath, Jeramiah J. Smith

Biology Faculty Publications

The sea lamprey (Petromyzon marinus) represents one of the few vertebrate species known to undergo large-scale programmatic elimination of genomic DNA over the course of its normal development. Programmed genome rearrangements (PGRs) result in the reproducible loss of ~20% of the genome from somatic cell lineages during early embryogenesis. Studies of PGR hold the potential to provide novel insights related to the maintenance of genome stability during the cell cycle and coordination between mechanisms responsible for the accurate distribution of chromosomes into daughter cells, yet little is known regarding the mechanistic basis or cellular context of PGR in …

De Novo Deciphering Three-Dimensional Chromatin Interaction And Topological Domains By Wavelet Transformation Of Epigenetic Profiles., Yong Chen, Yunfei Wang, Zhenyu Xuan, Min Chen, Michael Q Zhang

Faculty Scholarship for the College of Science & Mathematics

Defining chromatin interaction frequencies and topological domains is a great challenge for the annotations of genome structures. Although the chromosome conformation capture (3C) and its derivative methods have been developed for exploring the global interactome, they are limited by high experimental complexity and costs. Here we describe a novel computational method, called CITD, for de novo prediction of the chromatin interaction map by integrating histone modification data. We used the public epigenomic data from human fibroblast IMR90 cell and embryonic stem cell (H1) to develop and test CITD, which can not only successfully reconstruct the chromatin interaction frequencies discovered by …

Quantitative Mass Spectrometry Reveals Changes In Histone H2b Variants As Cells Undergo Inorganic Arsenic-Mediated Cellular Transformation, Matthew Rea, Tingting Jiang, Rebekah Eleazer, Meredith Eckstein, Alan G. Marshall, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Exposure to inorganic arsenic, a ubiquitous environmental toxic metalloid, leads to carcinogenesis. However, the mechanism is unknown. Several studies have shown that inorganic arsenic exposure alters specific gene expression patterns, possibly through alterations in chromatin structure. While most studies on understanding the mechanism of chromatin-mediated gene regulation have focused on histone post-translational modifications, the role of histone variants remains largely unknown. Incorporation of histone variants alters the functional properties of chromatin. To understand the global dynamics of chromatin structure and function in arsenic-mediated carcinogenesis, analysis of the histone variants incorporated into the nucleosome and their covalent modifications is required. Here …

The Spliceosomal Protein Sf3b5 Is A Novel Component Of Drosophila Saga That Functions In Gene Expression Independent Of Splicing, Rachel Stegeman, Peyton J. Spreacker, Selene K. Swanson, Robert Stephenson, Laurence Florens, Michael P. Washburn, Vikki M. Weake

Department of Biochemistry Faculty Publications

The interaction between splicing factors and the transcriptional machinery provides an intriguing link between the coupled processes of transcription and splicing. Here, we show that the two components of the SF3B complex, SF3B3 and SF3B5, that form part of the U2 small nuclear ribonucleoprotein particle (snRNP) are also subunits of the Spt-Ada-Gcn5 acetyltransferase (SAGA) transcriptional coactivator complex in Drosophila melanogaster. Whereas SF3B3 had previously been identified as a human SAGA subunit, SF3B5 had not been identified as a component of SAGA in any species. We show that SF3B3 and SF3B5 bind to SAGA independent of RNA and interact with …

Involvement Of Parp1 In The Regulation Of Alternative Splicing, Elena Matveeva, John Maiorano, Qingyang Zhang, Abdallah M. Eteleeb, Paolo Convertini, Jing Chen, Vittoria Infantino, Stefan Stamm, Jiping Wang, Eric C. Rouchka, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Specialized chromatin structures such as nucleosomes with specific histone modifications decorate exons in eukaryotic genomes, suggesting a functional connection between chromatin organization and the regulation of pre-mRNA splicing. Through profiling the functional location of Poly (ADP) ribose polymerase, we observed that it is associated with the nucleosomes at exon/intron boundaries of specific genes, suggestive of a role for this enzyme in alternative splicing. Poly (ADP) ribose polymerase has previously been implicated in the PARylation of splicing factors as well as regulation of the histone modification H3K4me3, a mark critical for co-transcriptional splicing. In light of these studies, we hypothesized that …

Nucleosome Distortion As A Possible Mechanism Of Transcription Activation Domain Function, Tamara Y. Erkina, Alexandre M. Erkine

Scholarship and Professional Work – COPHS

After more than three decades since the discovery of transcription activation domains (ADs) in gene-specific activators, the mechanism of their function remains enigmatic. The widely accepted model of direct recruitment by ADs of co-activators and basal transcriptional machinery components, however, is not always compatible with the short size yet very high degree of sequence randomness and intrinsic structural disorder of natural and synthetic ADs. In this review, we formulate the basis for an alternative and complementary model, whereby sequence randomness and intrinsic structural disorder of ADs are necessary for transient distorting interactions with promoter nucleosomes, triggering promoter nucleosome translocation and …

Linker Histone H1 And H3k56 Acetylation Are Antagonistic Regulators Of Nucleosome Dynamics, Morgan Bernier, Yi Luo, Kingsley C. Nwokelo, Michelle Goodwin, Sarah J. Dreher, Pei Zhang, Mark R. Parthun, Yvonne N. Fondufe-Mittendorf, Jennifer J. Ottesen, Michael G. Poirier

Molecular and Cellular Biochemistry Faculty Publications

H1 linker histones are highly abundant proteins that compact nucleosomes and chromatin to regulate DNA accessibility and transcription. However, the mechanisms that target H1 regulation to specific regions of eukaryotic genomes are unknown. Here we report fluorescence measurements of human H1 regulation of nucleosome dynamics and transcription factor (TF) binding within nucleosomes. H1 does not block TF binding, instead it suppresses nucleosome unwrapping to reduce DNA accessibility within H1-bound nucleosomes. We then investigated H1 regulation by H3K56 and H3K122 acetylation, two transcriptional activating histone post translational modifications (PTMs). Only H3K56 acetylation, which increases nucleosome unwrapping, abolishes H1.0 reduction of TF …