Genomics Commons^™

Cells And Networks In Flux: Rethinking Ontogenesis And Pathogenesis, Mark L. Tykocinski

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Organ and tissue functions emerge from the coordinated activity of cell networks. Therapeutics that act on pathogenic cell networks, modulating their cellular interplay, follow naturally. Over several decades, our laboratory has developed a series of approaches for rewiring cell networks, culminating in a class of cell surface-directed signal converter proteins (SCPs) that do so by modulating juxtacrine and autocrine signaling in and among their nodal cells. A first such SCP has now produced encouraging clinical data for cancer immunotherapy. Yet, these early network-directed fusion proteins rest on a deliberately simplified picture: discrete end-cell types plugged into graphically tractable networks. That …

Proteogenomics Of Hypertrophic Cardiomyopathy Reveals Subtype-Specific Therapy, Ke Ma, Jie Yang, Hongchang Guo, Ping Li, Xiaowei Li, Zhujun Dong, Jing Zhang, Congcong Zhang, Pengli Yang, Chongpei Hua, Shuolin Zhu, Guoqing Li, Jianchao Zhang, Ningyu Ding, Jizheng Wang, Xin-Liang Ma, Zhuofeng Lin, Jianzeng Dong, Yang Li, Yulin Li

Department of Emergency Medicine Faculty Papers

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a heterogeneous disease with diverse prognosis. The underlying mechanisms remain unknown, resulting in limited risk stratification and therapeutic strategies. This study aimed to elucidate molecular subtypes of HCM through integrated proteogenomic analysis and explore subtype-specific therapeutic strategies.

METHODS: We conducted an integrated proteogenomic analysis of 132 patients with HCM using myocardial samples, incorporating whole-exome sequencing, RNA sequencing, and proteomics. Unsupervised clustering was used to identify HCM subtypes, which were validated in heart tissues and human induced pluripotent stem cell-derived cardiomyocytes from 2 independent HCM subsets. Subtype-specific signatures and pathways were explored, and their causal link …

Disease-Causing Mfn2 Mutants Impair Mitochondrial Fission Dynamics By Distinct Drp1 Dysregulation, Daniel Lagos, Pamela R. De Santiago, Nicolás Pérez-Bravo, Benjamín Cartes-Saavedra, Josefa Vial-Brizzi, Diego Troncoso-Chandía, Oliver Podmanicky, Rita Horvath, Verónica Eisner

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mitochondria undergo fusion and fission. While DRP1 regulates fission, fusion is controlled by OPA1, MFN1, and MFN2. The balance between these processes and the crosstalk between machineries remains poorly understood. MFN2 mutations cause Charcot-Marie-Tooth disease type 2 A (CMT2A), affecting mitochondrial fusion and morphology. However, their role in fission is unclear. Using skin fibroblasts from CMT2A patients (L248H and M376V MFN2 mutations) and wild-type mouse embryonic fibroblasts expressing these variants, we studied how MFN2 mutations impact mitochondrial dynamics beyond fusion. We analyzed mitochondrial morphology and dynamics by live-cell confocal microscopy and tested fusion/fission protein levels, oxygen consumption rate (OCR), extracellular …

Diagnostic And Clinical Utility Of Oncoscan Microarray And Ngs-Based Sequencing In Pediatric Solid Tumors: Children’S Mercy Hospital’S Experience, Aravindh Nagarajan, Lisa Lansdon, Midhat Farooqi, Lei Zhang, Elena Repnikova

Research Days

This papers attempts to evaluate the diagnostic and clinical utility of microarray-based OS+ in detecting clinically relevant genetic alterations in FFPE solid tumor samples and to compare the yield of somatic mutation detection by WGS/WES in pediatric solid tumors at Children’s Mercy Hospital - Kansas City.

Early Hematopoietic Differentiation Of An Inducible Pluripotent Stem Cell Model Of Infant Lymphoblastic Leukemia, Meagan Vacek, Jacqelyn Nemechek, Irina Pushel, Bradley Thornton, Priyanka Kumar, Jay L. Vivian, John M. Perry

Research Days

This abstract describes our work regarding the differentiation of human inducible pluripotent stem cells into hematopoietic stem and progenitor cells as the groundwork for the development of a genomics driven inducible pluripotent stem cell model of KMT2A rearranged infant acute lymphoblastic leukemia.

Elucidating The Multi-Omics Of Early-Onset Colorectal Cancer, Jumanah Alshenaifi

Dissertations and Theses (Open Access)

The incidence and mortality rates of sporadic early-onset colorectal cancer have increased in recent decades, but there is no clear etiological basis for this trend. EOCRC is commonly defined as colon and rectal cancers diagnosed before the age of 50 years. The rising incidence of EOCRC has made it the second most common cancer and the third leading cause of cancer death in this age group. The rising incidence of EOCRC is also documented internationally in more than 20 countries across different continents. Clinically, EOCRC has a distinct, more aggressive clinical profile than LOCRC. While approximately 15% of EOCRC cases …

A Stakeholder-Informed Conceptual Framework For Evaluating Genomics In Precision Oncology, Julie A. Wiedower

All Dissertations

This dissertation explores the value of genomic testing in precision oncology with an emphasis on how US payers conceptualize and prioritize elements of value. This research aims to address gaps in understanding payer perspectives and proposes a stakeholder-informed framework for evaluating genomic testing in oncology. To achieve this aim, the presented research investigates payer perspectives, value-based cancer care priorities, and the conceptual understanding of the value of a genetic diagnosis to establish a framework for value with the payer audience in mind. Chapter 1 outlines relevant background information relating to the genomic revolution and challenges in translating genomic testing technologies …

The Genomic Landscape And Prognostic Impact Of Kras, Stk11, And Smarca4 Mutations And Co-Mutations On Survival Outcomes In Non-Small Cell Lung Cancer, Peter Manolakos

All Dissertations

Non-small lung cancer (NSCLC) accounts for 85% of lung cancer cases, and Kirsten rat sarcoma viral oncogene homolog (KRAS), Serine/Threonine Kinase 11 (STK11), and SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4 (SMARCA4) mutations and co-mutations have been increasingly recognized for their potential prognostic significance. However, clear knowledge gaps remain regarding which treatments should be selected for patients who present clinically with KRAS/STK11 or KRAS/SMARCA4 co-mutations, as outlined in Chapter 1. Despite significant clinical development advancements in immunotherapy and targeted therapy, a deeper understanding of the influence of these genomic …

Hierarchical Lineage Tracing To Unravel Mechanisms Of Cancer Treatment Resistance, Rachel Danielle Saxe

Dartmouth College Ph.D Dissertations

Cancer cells adapt to treatment, leading to the emergence of clones that are more aggressive and resistant to anti-cancer therapies. We have a limited understanding of the development of treatment resistance as we lack technologies to map the evolution of cancer under the selective pressure of treatment. To address this, we developed a hierarchical, dynamic lineage tracing method called FLARE (Following Lineage Adaptation and Resistance Evolution). We use this technique to track the progression of acute myeloid leukemia (AML) cell lines through exposure to Cytarabine (AraC), a front-line treatment in AML, in vitro and in vivo. We map distinct cellular …

Differential Impacts On Proteoglycan Expression In The Response To Lens Wounding In Reparative And Pro-Fibrotic Microenvironments, Janice L Walker, A. Sue Menko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Ex vivo lens epithelial explant cultures created through a technique that mimics cataract surgery provided an ideal model with which to compare the impacts on proteoglycan expression in the response to wounding in both reparative promoting and pro-fibrotic microenvironments. On their native basement membrane capsule the injured lens epithelium undergoes regenerative repair, with the wound closing within a few days. Their migration across the wound area is led by a population of activated lens resident immune cells. The same leader cell population also directs the wounded epithelium to migrate off the outside edges of the lens explant across the surrounding …

Zic1 Is A Context-Dependent Medulloblastoma Driver In The Rhombic Lip, John J Y Lee, Ran Tao, Zhen You, Parthiv Haldipur, Anders W Erickson, Hamza Farooq, Liam D Hendriske, Namal Abeysundara, Cory M Richman, Evan Y Wang, Neha Das Gupta, Jennifer Hadley, Melissa Batts, Christopher W Mount, Xiaochong Wu, Alex Rasnitsyn, Swneke Bailey, Florence M G Cavalli, Sorana Morrissy, Livia Garzia, Kulandaimanuvel Antony Michealraj, Abhi Visvanathan, Vernon Fong, Jonelle Palotta, Raul Suarez, Bryn G Livingston, Miao Liu, Betty Luu, Craig Daniels, James Loukides, Anne Bendel, Pim J French, Johan M Kros, Andrey Korshunov, Marcel Kool, Fernando Chico Ponce De León, Mario Perezpeña-Diazconti, Boleslaw Lach, Sheila K Singh, Sarah E S Leary, Byung-Kyu Cho, Seung-Ki Kim, Kyu-Chang Wang, Ji-Yeoun Lee, Teiji Tominaga, William A Weiss, Joanna J Phillips, Shizhong Dai, Gelareh Zadeh, Ali G Saad, László Bognár, Almos Klekner, Ian F Pollack, Ronald L Hamilton, Young-Shin Ra, Wieslawa A Grajkowska, Marta Perek-Polnik, Reid C Thompson, Anna M Kenney, Michael K Cooper, Stephen C Mack, Nada Jabado, Mathieu Lupien, Marco Gallo, Vijay Ramaswamy, Mario L Suva, Hiromichi Suzuki, Kathleen J Millen, L Frank Huang, Paul A Northcott, Michael D Taylor

Faculty, Staff and Students Publications

Transcription factors are frequent cancer driver genes, exhibiting noted specificity based on the precise cell of origin. We demonstrate that ZIC1 exhibits loss-of-function (LOF) somatic events in group 4 (G4) medulloblastoma through recurrent point mutations, subchromosomal deletions and mono-allelic epigenetic repression (60% of G4 medulloblastoma). In contrast, highly similar SHH medulloblastoma exhibits distinct and diametrically opposed gain-of-function mutations and copy number gains (20% of SHH medulloblastoma). Overexpression of ZIC1 suppresses the growth of group 3 medulloblastoma models, whereas it promotes the proliferation of SHH medulloblastoma precursor cells. SHH medulloblastoma ZIC1 mutants show increased activity versus wild-type ZIC1, whereas G4 medulloblastoma …

Analysis Of Differential Gene Expression In Androgen-Independent Clones Derived From The Mycap Pca Cell Line, Jessie L. Tignor, Melanie Sinanian, Richard Inho Joh, David Gewirtz, Jason Reed

Undergraduate Research Posters

Androgen deprivation therapy (ADT) is a primary treatment strategy for prostate cancer (PCa), yet many tumors eventually develop androgen independence, leading to treatment resistance. To investigate the molecular changes underlying this transition, we analyzed differential gene expression in four androgen-independent (AI) clones derived from the Myc-CaP prostate cancer cell line using RNA sequencing. Gene expression profiles were compared to the parental Myc-CaP line, and differentially expressed genes (DEGs) were identified using DESeq2 and edgeR. The AI clones exhibited significant downregulation of senescence-associated genes, including Ezh2 and lamin B1, suggesting a loss of senescence-related chromatin repression. Additionally, upregulation of Wnt pathway …

Transcriptional Regulation In The Absence Of Inositol Trisphosphate Receptor Calcium Signaling, Michael Young, David M. Booth, David Smith, Marco Tigano, György Hajnóczky, Suresh K. Joseph

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The activation of IP3 receptor (IP3R) Ca2+ channels generates agonist-mediated Ca2+ signals that are critical for the regulation of a wide range of biological processes. It is therefore surprising that CRISPR induced loss of all three IP3R isoforms (TKO) in HEK293 and HeLa cell lines yields cells that can survive, grow and divide, albeit more slowly than wild-type cells. In an effort to understand the adaptive mechanisms involved, we have examined the activity of key Ca2+ dependent transcription factors (NFAT, CREB and AP-1) and signaling pathways using luciferase-reporter assays, phosphoprotein immunoblots and whole genome transcriptomic studies. In addition, the diacylglycerol …

Multi-Organ Gene Expression Analysis And Network Modeling Reveal Regulatory Control Cascades During The Development Of Hypertension In Female Spontaneously Hypertensive Rat, Eden Hornung, Sirisha Achanta, Alison Moss, James S. Schwaber, Rajanikanth Vadigepalli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Hypertension is a multifactorial disease with stage-specific gene expression changes occurring in multiple organs over time. The temporal sequence and the extent of gene regulatory network changes occurring across organs during the development of hypertension remain unresolved. In this study, female spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) rats were used to analyze expression patterns of 96 genes spanning inflammatory, metabolic, sympathetic, fibrotic, and renin-angiotensin (RAS) pathways in five organs, at five time points from the onset to established hypertension. We analyzed this multi-dimensional dataset containing ~15,000 data points and developed a data-driven dynamic network model that accounts for …

Decoding Complex Inherited Phenotypes In Rare Disorders: The Decipherd Initiative For Rare Undiagnosed Diseases In Chile, M Cecilia Poli, Boris Rebolledo-Jaramillo, Catalina Lagos, Joan Orellana, Gabriela Moreno, Luz M Martín, Gonzalo Encina, Daniela Böhme, Víctor Faundes, M Jesús Zavala, Trinidad Hasbún, Sara Fischer, Florencia Brito, Diego Araya, Manuel Lira, Javiera De La Cruz, Camila Astudillo, Guillermo Lay-Son, Carolina Cares, Mariana Aracena, Esteban San Martin, Zeynep Coban-Akdemir, Jennifer E Posey, James R Lupski, Gabriela M Repetto

Faculty, Staff and Students Publications

Rare diseases affect millions of people worldwide, and most have a genetic etiology. The incorporation of next-generation sequencing into clinical settings, particularly exome and genome sequencing, has resulted in an unprecedented improvement in diagnosis and discovery in the past decade. Nevertheless, these tools are unavailable in many countries, increasing health care gaps between high- and low-and-middle-income countries and prolonging the "diagnostic odyssey" for patients. To advance genomic diagnoses in a setting of limited genomic resources, we developed DECIPHERD, an undiagnosed diseases program in Chile. DECIPHERD was implemented in two phases: training and local development. The training phase relied on international …

Project Give: Using A Virtual Genetics Service Platform To Reduce Health Inequities And Improve Access To Genomic Care In An Underserved Region Of Texas, Blake Vuocolo, Roberta Sierra, Daniel Brooks, Christopher Holder, Lauren Urbanski, Keila Rodriguez, Jose David Gamez, Surya Narayan Mulukutla, Ana Hernandez, Alberto Allegre, Humberto Hidalgo, Sarah Rodriguez, Sandy Magallan, Jeremy Gibson, Juan Carlos Bernini, Melanie Watson, Robert Nelson, Lizbeth Mellin-Sanchez, Nancy Garcia, Lori Berry, Hongzheng Dai, Claudia Soler-Alfonso, Kent Carter, Brendan Lee, Seema R Lalani

Faculty, Staff and Students Publications

BACKGROUND: The utilization of genomic information to improve health outcomes is progressively becoming more common in clinical practice. Nonetheless, disparities persist in accessing genetic services among ethnic minorities, individuals with low socioeconomic status, and other vulnerable populations. The Rio Grande Valley (RGV) at the Texas-Mexico border is predominantly Hispanic/Latino with a high poverty rate and very limited access to genetic services. Funded by the National Center for Advancing Translational Sciences, Project GIVE (Genetic Inclusion by Virtual Evaluation) was launched in 2022 to reduce the time to diagnosis and increase provider knowledge of genomics in this region, with the goal of …

Whole Genome And Reverse Protein Phase Array Landscapes Of Patient Derived Osteosarcoma Xenograft Models, Chia-Chin Wu, Licai Huang, Zhongting Zhang, Zhenlin Ju, Xingzhi Song, E Anders Kolb, Wendong Zhang, Jonathan Gill, Min Ha, Malcolm A Smith, Peter Houghton, Christopher L Morton, Raushan Kurmasheva, John Maris, Yael Mosse, Yiling Lu, Richard Gorlick, P Andrew Futreal, Hannah C Beird

Faculty, Staff and Student Publications

Osteosarcoma is the most common primary bone malignancy in children and young adults, and it has few treatment options. As a result, there has been little improvement in survival outcomes in the past few decades. The need for models to test novel therapies is especially great in this disease since it is both rare and does not respond to most therapies. To address this, an NCI-funded consortium has characterized and utilized a panel of patient-derived xenograft models of osteosarcoma for drug testing. The exomes, transcriptomes, and copy number landscapes of these models have been presented previously. This study now adds …

3d Chromatin Architecture, Brd4, And Mediator Have Distinct Roles In Regulating Genome-Wide Transcriptional Bursting And Gene Network, Pawel Trzaskoma, Seolkyoung Jung, Aleksandra Pękowska, Christopher H Bohrer, Xiang Wang, Faiza Naz, Stefania Dell'orso, Wendy D Dubois, Ana Olivera, Supriya V Vartak, Yongbing Zhao, Subhashree Nayak, Andrew Overmiller, Maria I Morasso, Vittorio Sartorelli, Daniel R Larson, Carson C Chow, Rafael Casellas, John J O'Shea

Faculty, Staff and Student Publications

Discontinuous transcription is evolutionarily conserved and a fundamental feature of gene regulation; yet, the exact mechanisms underlying transcriptional bursting are unresolved. Analyses of bursting transcriptome-wide have focused on the role of cis-regulatory elements, but other factors that regulate this process remain elusive. We applied mathematical modeling to single-cell RNA sequencing data to infer bursting dynamics transcriptome-wide under multiple conditions to identify possible molecular mechanisms. We found that Mediator complex subunit 26 (MED26) primarily regulates frequency, MYC regulates burst size, while cohesin and Bromodomain-containing protein 4 (BRD4) can modulate both. Despite comparable effects on RNA levels among these perturbations, acute depletion …

Crispr-Cas9 And Cas12a Target Site Richness Reflects Genomic Diversity In Natural Populations Of Anopheles Gambiae And Aedes Aegypti Mosquitoes, Travis C Collier, Yoosook Lee, Derrick K Mathias, Víctor López Del Amo

Faculty, Staff and Student Publications

Due to limitations in conventional disease vector control strategies including the rise of insecticide resistance in natural populations of mosquitoes, genetic control strategies using CRISPR gene drive systems have been under serious consideration. The identification of CRISPR target sites in mosquito populations is a key aspect for developing efficient genetic vector control strategies. While genome-wide Cas9 target sites have been explored in mosquitoes, a precise evaluation of target sites focused on coding sequence (CDS) is lacking. Additionally, target site polymorphisms have not been characterized for other nucleases such as Cas12a, which require a different DNA recognition site (PAM) and would …

Ocular Gene Transfer In The Spotlight: Implications Of Newspaper Content For Clinical Communications, Shelly Benjaminy, Tania M. Bubela

Office of the Provost

Background: Ocular gene transfer clinical trials are raising hopes for blindness treatments and attracting media attention. News media provide an accessible health information source for patients and the public, but are often criticized for overemphasizing benefits and underplaying risks of novel biomedical interventions. Overly optimistic portrayals of unproven interventions may influence public and patient expectations; the latter may cause patients to downplay risks and over-emphasize benefits, with implications for informed consent for clinical trials. We analyze the news media communications landscape about ocular gene transfer and make recommendations for improving communications between clinicians and potential trial participants in light of …

Maldi Imaging Mass Spectrometry Visualizes The Distribution Of Antidepressant Duloxetine And Its Major Metabolites In Mouse Brain, Liver, Kidney, And Spleen Tissues, Saleh M Khalil, Xuan Qin, John M Hakenjos, Jian Wang, Zhaoyong Hu, Xinli Liu, Jin Wang, Mirjana Maletic-Savatic, Kevin R Mackenzie, Martin M Matzuk, Feng Li

Faculty, Staff and Student Publications

Imaging mass spectrometry (IMS) is a powerful tool for mapping the spatial distribution of unlabeled drugs and metabolites that may find application in assessing drug delivery, explaining drug efficacy, and identifying potential toxicity. This study focuses on determining the spatial distribution of the antidepressant duloxetine, which is widely prescribed despite common adverse effects (liver injury, constant headaches) whose mechanisms are not fully understood. We used high-resolution IMS with matrix-assisted laser desorption/ionization to examine the distribution of duloxetine and its major metabolites in four mouse organs where it may contribute to efficacy or toxicity: brain, liver, kidney, and spleen. In none …

Effects Of Protein-Enriched Nutritional Support On Skeletal Muscle Mass And Rehabilitative Outcomes In Brain Tumor Patients: A Randomized Controlled Trial, Kye Hee Cho, Eun Young Han, Min Kyu Jung, Chang Moo Kang, Ji Cheol Shin, Sang Hee Im

Faculty, Staff and Student Publications

Patients with brain tumors require extensive and prolonged rehabilitation efforts as they suffer from lesion-induced motor weakness as well as treatment-related side effects, often leading to a significant decline in function. Protein supplements have shown positive effects on promoting muscle strength and physical performance in various tumor etiologies. However, reports on their effects specifically in brain tumor patients remain scarce. This study aims to investigate the feasibility and efficacy of protein supplements in enhancing rehabilitative outcomes via muscle strengthening and functional gain in brain tumor patients with neurological demise. Sixty brain tumor patients were randomly assigned to either a protein …

Improving Access To Exome Sequencing In A Medically Underserved Population Through The Texome Project, Blake Vuocolo, Ryan J German, Seema R Lalani, Chaya N Murali, Carlos A Bacino, Stephanie Baskin, Rebecca Littlejohn, John D Odom, Scott Mclean, Carrie Schmid, Morgan Nutter, Melissa Stuebben, Emily Magness, Olivia Juarez, Dina El Achi, Bailey Mitchell, Kevin E Glinton, Laurie Robak, Sandesh C S Nagamani, Lisa Saba, Adasia Ritenour, Lilei Zhang, Haley Streff, Katie Chan, K Jordan Kemere, Kent Carter, Texome Project, Nichole Owen, Liesbeth Vossaert, Pengfei Liu, Hugo Bellen, Michael F Wangler

Faculty, Staff and Students Publications

PURPOSE: Genomic medicine can end diagnostic odysseys for patients with complex phenotypes; however, limitations in insurance coverage and other systemic barriers preclude individuals from accessing comprehensive genetics evaluation and testing.

METHODS: The Texome Project is a 4-year study that reduces barriers to genomic testing for individuals from underserved and underrepresented populations. Participants with undiagnosed, rare diseases who have financial barriers to obtaining exome sequencing (ES) clinically are enrolled in the Texome Project.

RESULTS: We highlight the Texome Project process and describe the outcomes of the first 60 ES results for study participants. Participants received a genetic evaluation, ES, and return …

An Unexpected Path For Malat1 In Neurons: Trafficking Out Of The Nucleus For Translation, Bradley W Wright, Jeremy E Wilusz

Faculty, Staff and Students Publications

The Malat1 (metastasis-associated lung adenocarcinoma transcript 1) long noncoding RNA is highly and broadly expressed in mammalian tissues, accumulating in the nucleus where it modulates expression and pre-mRNA processing of many protein-coding genes. In this issue of Genes & Development, Xiao and colleagues (doi:10.1101/gad.351557.124) report that a significant fraction of Malat1 transcripts in cultured mouse neurons are surprisingly exported from the nucleus. These transcripts are packaged with Staufen proteins in RNA granules and traffic down the lengths of neurites. They then can be released in a stimulus-dependent manner to be locally translated into a microprotein that alters neuronal gene …

A Genomics Driven Induced Pluripotent Stem Cell Model Of Infant Acute Lymphoblastic Leukemia - Early Results, Meagan Vacek, Jacqelyn Nemechek, Irina Pushel, Bradley Thornton, Molly Leyda, Priyanka Prem Kumar, Midhat Farooqi, Jay L. Vivian, Erin M. Guest, John M. Perry

Research Days

While the cure rates for pediatric ALL have improved over the decades, infants with ALL (iALL) have not benefitted from these advances and continue to have a devastating prognosis. Unfortunately progress in treatment has also been slowed by inadequate research models. With this project, we address this unmet need by investigating a novel model to understand the cellular and molecular changes that occur during iALL onset and progression.

Cis-Regulatory Mechanisms Through Stages Of Erythroid Regenration, Yichao Zhou

Theses & Dissertations

Produced by steady state erythropoiesis, erythrocytes serve as vital regulators of metabolism and life by delivering oxygen to all the cells and tissues. Under acute anemia, steady state erythropoiesis is not sufficient to produce enough erythrocytes, leading to distinct mechanisms needed to regenerate large numbers of mature erythrocytes rapidly. Erythroid regeneration occurs in four stages: activation, expansion and differentiation, resolution, and post-resolution, according to the dynamics of erythrocyte numbers and progenitor activity. Erythroid regeneration throughout this timeline requires some critical extracellular cues, but the intrinsic molecular mechanisms needed to accelerate and decelerate the activity of erythroid progenitors in anemia and …

Structural Basis Of Dna Crossover Capture By Escherichia Coli Dna Gyrase, Marlène Vayssières, Nils Marechal, Long Yun, Brian Lopez Duran, Naveen Kumar Murugasamy, Jonathan M Fogg, Lynn Zechiedrich, Marc Nadal, Valérie Lamour

Faculty, Staff and Students Publications

DNA supercoiling must be precisely regulated by topoisomerases to prevent DNA entanglement. The interaction of type IIA DNA topoisomerases with two DNA molecules, enabling the transport of one duplex through the transient double-stranded break of the other, remains elusive owing to structures derived solely from single linear duplex DNAs lacking topological constraints. Using cryo–electron microscopy, we solved the structure of Escherichia coli DNA gyrase bound to a negatively supercoiled minicircle DNA. We show how DNA gyrase captures a DNA crossover, revealing both conserved molecular grooves that accommodate the DNA helices. Together with molecular tweezer experiments, the structure shows that the …

Nodal Variants Are Associated With A Continuum Of Laterality Defects From Simple D-Transposition Of The Great Arteries To Heterotaxy, Zain Dardas, Jawid M Fatih, Angad Jolly, Moez Dawood, Haowei Du, Christopher M Grochowski, Edward G Jones, Shalini N Jhangiani, Xander H T Wehrens, Pengfei Liu, Weimin Bi, Eric Boerwinkle, Jennifer E Posey, Donna M Muzny, Richard A Gibbs, James R Lupski, Zeynep Coban-Akdemir, Shaine A Morris

Faculty, Staff and Student Publications

BACKGROUND: NODAL signaling plays a critical role in embryonic patterning and heart development in vertebrates. Genetic variants resulting in perturbations of the TGF-β/NODAL signaling pathway have reproducibly been shown to cause laterality defects in humans. To further explore this association and improve genetic diagnosis, the study aims to identify and characterize a broader range of NODAL variants in a large number of individuals with laterality defects.

METHODS: We re-analyzed a cohort of 321 proband-only exomes of individuals with clinically diagnosed laterality congenital heart disease (CHD) using family-based, rare variant genomic analyses. To this cohort we added 12 affected subjects with …

Genome-Wide Crispr Screen Reveals The Synthetic Lethality Between Bcl2l1 Inhibition And Radiotherapy, Ling Yin, Xiaoding Hu, Guangsheng Pei, Mengfan Tang, You Zhou, Huimin Zhang, Min Huang, Siting Li, Jie Zhang, Citu Citu, Zhongming Zhao, Bisrat G Debeb, Xu Feng, Junjie Chen

Faculty, Staff and Student Publications

Radiation therapy (RT) is one of the most commonly used anticancer therapies. However, the landscape of cellular response to irradiation, especially to a single high-dose irradiation, remains largely unknown. In this study, we performed a whole-genome CRISPR loss-of-function screen and revealed temporal inherent and acquired responses to RT. Specifically, we found that loss of the IL1R1 pathway led to cellular resistance to RT. This is in part because of the involvement of radiation-induced IL1R1-dependent transcriptional regulation, which relies on the NF-κB pathway. Moreover, the mitochondrial anti-apoptotic pathway, particularly the BCL2L1 gene, is crucially important for cell survival after radiation. BCL2L1 …

Grb2 Stabilizes Rad51 At Reversed Replication Forks Suppressing Genomic Instability And Innate Immunity Against Cancer, Zu Ye, Shengfeng Xu, Yin Shi, Xueqian Cheng, Yuan Zhang, Sunetra Roy, Sarita Namjoshi, Michael A Longo, Todd M Link, Katharina Schlacher, Guang Peng, Dihua Yu, Bin Wang, John A Tainer, Zamal Ahmed

Faculty, Staff and Student Publications

Growth factor receptor-bound protein 2 (GRB2) is a cytoplasmic adapter for tyrosine kinase signaling and a nuclear adapter for homology-directed-DNA repair. Here we find nuclear GRB2 protects DNA at stalled replication forks from MRE11-mediated degradation in the BRCA2 replication fork protection axis. Mechanistically, GRB2 binds and inhibits RAD51 ATPase activity to stabilize RAD51 on stalled replication forks. In GRB2-depleted cells, PARP inhibitor (PARPi) treatment releases DNA fragments from stalled forks into the cytoplasm that activate the cGAS-STING pathway to trigger pro-inflammatory cytokine production. Moreover in a syngeneic mouse metastatic ovarian cancer model, GRB2 depletion in the context of PARPi treatment …