Cell and Developmental Biology Commons^™

Elucidating Genotype-Phenotype Relationships In Bcs1l Mutations, Kalina Reese, Shannon Stewart, Rachael Baker, Amy Wilstermann

Summer Research

• Establish a yeast model system for the study of BCS1L function.
• Develop assays to investigate differences in mitochondrial efficiency and electron transport chain functionality of BCS1L mutants.
• Connect hearing-loss associated BCS1L mutations to mitochondrial structure and function to better explain the clinical variation observed in patients with BCS1L mutations

Mlk Book Read 2018 (Research Materials), Holy Cross Libraries

Library Resources for Campus Events

A bibliography of resources available through the Holy Cross Libraries which provide additional information related to the MLK Winter Book Read, based on the best-seller “The Immortal LIfe of Henrietta Lacks” by Rebecca Skoot.

Altered Ratio Of T Follicular Helper Cells To T Follicular Regulatory Cells Correlates With Autoreactive Antibody Response In Simian Immunodeficiency Virus–Infected Rhesus Macaques, Wenjin Fan, Andrew James Demers, Yanmin Wan, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

Individuals with chronic HIV-1 infection have an increased prevalence of autoreactive Abs. Many of the isolated HIV broadly neutralizing Abs from these individuals are also autoreactive. However, the underlying mechanism(s) that produce these autoreactive broadly neutralizing Abs remains largely unknown. The highly regulated coordination among B cells, T follicular helper (T_FH) cells, and T follicular regulatory (T_FR) cells in germinal centers (GCs) of peripheral lymphatic tissues (LTs) is essential for defense against pathogens while also restricting autoreactive responses. We hypothesized that an altered ratio of T_FH/T_FR cells in the GC contributes to the …

Superresolved Three-Dimensional Analysis Of The Spatial Arrangement Of The Human Immunodeficiency Virus Type-1 (Hiv-1) Envelope Glycoprotein At Sites Of Viral Assembly, Carmen Anne Buttler

Electronic Theses and Dissertations

Human Immunodeficiency Virus type 1 (HIV-1) replicates by forcing infected host cells to produce new virus particles, which assemble form protein components on the inner leaflet of the host cell's plasma membrane. This involves incorporation of the essential viral envelope glycoprotein (Env) into a structural lattice of viral Gag proteins. The mechanism of Env recruitment and incorporation is not well understood. To better define this process, we seek to describe the timing of Env-Gag encounters during particle assembly by measuring angular positions of Env proteins about the surfaces of budding particles. Using three-dimensional superresolution microscopy, we show that Env distributions …

Effects Of Adolescent Thc Exposure On The Prefrontal Gabaergic System: Implications For Schizophrenia-Related Psychopathology., Justine Renard, Walter J Rushlow, Steven R Laviolette

Anatomy and Cell Biology Publications

Marijuana is the most commonly used drug of abuse among adolescents. Considerable clinical evidence supports the hypothesis that adolescent neurodevelopmental exposure to high levels of the principal psychoactive component in marijuana, -delta-9-tetrahydrocanabinol (THC), is associated with a high risk of developing psychiatric diseases, such as schizophrenia later in life. This marijuana-associated risk is believed to be related to increasing levels of THC found within commonly used marijuana strains. Adolescence is a highly vulnerable period for the development of the brain, where the inhibitory GABAergic system plays a pivotal role in the maturation of regulatory control mechanisms in the central nervous …

The Impact Of Seasonal Operating Room Closures On Wait Times For Oral Cancer Surgery, Neil Mundi, Julie Theurer, A Warner, J Yoo, K. Fung, D. Macneil, S. Dhaliwal, Eric Winquist, David Palma, A. C. Nichols

Anatomy and Cell Biology Publications

Background

Operating room slowdowns occur at specific intervals in the year as a cost-saving measure. We aim to investigate the impact of these slowdowns on the care of oral cavity cancer patients at a Canadian tertiary care centre.

Methods

A total of 585 oral cavity cancer patients seen between 1999 and 2015 at the London Health Science Centre (lhsc) Head and Neck Multidisciplinary Clinic were included in this study. Operating room hours and patient load from 2006 to 2014 were calculated. Our primary endpoint was the wait time from consultation to definitive surgery. Exposure variables were defined according to wait …

Evaluating The Interaction Between The Human Melanocortin-2 Receptor And The Accessory Protein, Mrap1: Chimeric Receptor And Alanine Substitution Studies On Transmembrane Domain 4, Extracellular Loop 2, And Transmembrane Domain 5, Perry Victoria Davis

Electronic Theses and Dissertations

The melanocortin-2 receptor (MC2R) is the most complex due to its trafficking and ligand selectivity requirements for proper activation. The MC2R requires the melanocortin receptor accessory protein-1 (MRAP1) for proper trafficking and activation of the receptor by the melanocortin hormone, ACTH. MRAP1 is a single transmembrane-spanning domain protein that creates a homodimer with another MRAP1 protein. Furthermore, MRAP2 creates a heterodimer with the MC2R. Previous studies have shown that the MRAP1 protein contains an activation motif required for activation of MC2R and this activation motif located on the extracellular space side of the plasma membrane of the cell. The objective …

Mucosal Antibody Responses To Vaccines Targeting Siv Protease Cleavage Sites Or Fulllength Gag And Env Proteins In Mauritian Cynomolgus Macaques, Hongzhao Li, Yan Hai, So-Yon Lim, Nikki Toledo, Jose Crecente-Campo, Dane Schalk, Lin Li, Robert W. Omange, Tamara G. Dacoba, Lewis R. Liu, Mohammad Abul Kashem, Yanmin Wan, Binhua Liang, Qingsheng Li, Eva Rakasz, Nancy Schultz-Darken, Maria J. Alonso, Francis A. Plummer, James B. Whitney, Ma Luo

Nebraska Center for Virology: Faculty Publications

HIV mutates rapidly and infects CD4⁺ T cells, especially when they are activated. A vaccine targeting conserved, essential viral elements while limiting CD4⁺ T cell activation could be effective. Learning from natural immunity observed in a group of highly HIV-1 exposed seronegative Kenyan female sex workers, we are testing a novel candidate HIV vaccine targeting the 12 viral protease cleavage sites (PCSs) (the PCS vaccine), in comparison with a vaccine targeting full-length Gag and Env (the Gag/Env vaccine) in a Mauritian cynomolgus macaque/SIV model. In this study we evaluated these vaccines for induction of mucosal antibodies to SIV …

Sodium Bicarbonate Cotransporter Nbce2 Gene Variants Increase Sodium And Bicarbonate Transport In Human Renal Proximal Tubule Cells., John J Gildea, Peng Xu, Brandon A Kemp, Julia M Carlson, Hanh T Tran, Dora Bigler Wang, Christophe J Langouët-Astrié, Helen E Mcgrath, Robert M Carey, Pedro A Jose, Robin A Felder

Medicine Faculty Publications

RATIONALE: Salt sensitivity of blood pressure affects >30% of the hypertensive and >15% of the normotensive population. Variants of the electrogenic sodium bicarbonate cotransporter NBCe2 gene, SLC4A5, are associated with increased blood pressure in several ethnic groups. SLC4A5 variants are also highly associated with salt sensitivity, independent of hypertension. However, little is known about how NBCe2 contributes to salt sensitivity, although NBCe2 regulates renal tubular sodium bicarbonate transport. We hypothesized that SLC4A5 rs10177833 and rs7571842 increase NBCe2 expression and human renal proximal tubule cell (hRPTC) sodium transport and may be a cause of salt sensitivity of blood pressure.

OBJECTIVE: To …

Epha2/Ephrin-A1 Mediate Corneal Epithelial Cell Compartmentalization Via Adam10 Regulation Of Egfr Signaling., Nihal Kaplan, Rosa Ventrella, Han Peng, Sonali Pal-Ghosh, Constadina Arvanitis, Joshua Z Rappoport, Brian J Mitchell, Mary Ann Stepp, Robert M Lavker, Spiro Getsios

Anatomy and Regenerative Biology Faculty Publications

Purpose: Progenitor cells of the limbal epithelium reside in a discrete area peripheral to the more differentiated corneal epithelium and maintain tissue homeostasis. What regulates the limbal-corneal epithelial boundary is a major unanswered question. Ephrin-A1 ligand is enriched in the limbal epithelium, whereas EphA2 receptor is concentrated in the corneal epithelium. This reciprocal pattern led us to assess the role of ephrin-A1 and EphA2 in limbal-corneal epithelial boundary organization.

Methods: EphA2-expressing corneal epithelial cells engineered to express ephrin-A1 were used to study boundary formation in vitro in a manner that mimicked the relative abundance of these juxtamembrane signaling proteins in …

48839 (Gmr19b04), Neha Gogia, Ankita Sarkar, Amit Singh

Dpp Enhancer Sequences Utilized in GMR Line

dpp enhancer - 48839

• Id - GMR19B04,
• Location - 2L:2432214,2435785
• Base pairs – 3571 bp

47472 (Gmr16g02), Neha Gogia, Ankita Sarkar, Amit Singh

Dpp Enhancer Sequences Utilized in GMR Line

dpp enhancer - 47472

• Id - GMR16G02
• Location 2L:2425041, 2428154
• Base pairs – 3113 bp

48770 (Gmr17e04), Neha Gogia, Ankita Sarkar, Amit Singh

Dpp Enhancer Sequences Utilized in GMR Line

dpp enhancer - 48770

• Id - GMR17E04
• Location 2L: 2428913..2432834
• Base pairs – 3921 bp

Studies Of Norspermidine Uptake In Drosophila Suggest The Existence Of Multiple Polyamine Transport Pathways, Michael Dieffenbach

Honors Undergraduate Theses

Polyamines are a class of essential nutrients involved in many basic cellular processes such as gene expression, cell proliferation, and apoptosis. Without polyamines, cell growth is delayed or halted. Cancerous cells require an abundance of polyamines through a combination of synthesis and transport from the extracellular environment. An FDA-approved drug, D,L-α-difluoromethylornithine (DFMO), blocks polyamine synthesis but is ineffective at inhibiting cell growth due to polyamine transport. Thus, there is a need to develop drugs that inhibit polyamine transport to use in combination with DFMO. Surprisingly, little is known about the polyamine transport system in humans and other eukaryotes. Understanding the …

Selective Inhibition Of Ctcf Binding By Ias Directs Tet-Mediated Reprogramming Of 5-Hydroxymethylation Patterns In Ias-Transformed Cells, Matthew Rea, Tyler Gripshover, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Methylation at cytosine (5mC) is a fundamental epigenetic DNA modification recently associated with iAs-mediated carcinogenesis. In contrast, the role of 5-hydroxymethylcytosine (5hmC), the oxidation product of 5mC in iAs-mediated carcinogenesis is unknown. Here we assess the hydroxymethylome in iAs-transformed cells, showing that dynamic modulation of hydroxymethylated DNA is associated with specific transcriptional networks. Moreover, this pathologic iAs-mediated carcinogenesis is characterized by a shift toward a higher hydroxymethylation pattern genome-wide. At specific promoters, hydroxymethylation correlated with increased gene expression. Furthermore, this increase in hydroxymethylation occurs concurrently with an upregulation of ten-eleven translocation (TET) enzymes that oxidize 5-methylcytosine (5mC) in DNA. To …

The Identification And Segmentation Of Astrocytoma Prior To Critical Mass, By Means Of A Volumetric/Subregion Regression Analysis Of Normal And Neoplastic Brain Tissue, Lyn Higgins

Electronic Theses and Dissertations

As the underlying cause of Glioblastoma Multiforme (GBM) is presently unclear, this research implements a new approach to identifying and segmenting plausible instances of GBM prior to critical mass. Grade-IV Astrocytoma, or GBM, is an aggressive and malignant cancer arising from star-shaped glial cells, or astrocytes, where the astrocytes, functionally, assist in the support and protection of neurons within the central nervous system and spinal cord. Subsequently, our motivation for researching the ability to recognize GBM is that the underlying cause of the mutation is presently unclear, leading to the operative that GBM is only detectable through a combination of …

Pkc-Dependent Phosphorylation Of Munc18a At Ser313 In Activated Rbl-2h3 Cells, Pratikshya Adhikari, Hao Xu

Faculty Publications

Protein Kinase C (PKC) regulates the release of pro-inflammatory compounds from IgE/antigen-activated mast cells by unknown mechanisms. In this study, we show for the first time that PKC inhibitor Ro-03-0432, which inhibits RBL-2H3 exocytosis/degranulation in a concentration-dependent fashion, prevents the phosphorylation of membrane fusion factor Munc18a at Ser 313. Our study provides fresh evidence that PKC-dependent protein phosphorylation may contribute to the intricate regulation of mast cell degranulation by directly targeting the fusion factors.

Functional Analysis Of Protease Adamts 6 During Vertebrate Eye Formation, Austin Taylor

Lewis Honors College Capstone Collection

Extracellular matrix (ECM) remodeling and epithelial sheet fusion occur during the development of many different tissues, including the vertebrate eye (Lu et al., 2011) (Pai et al., 2012). During morphogenesis of the eye, the ventral hemisphere of the developing retinal tissue forms an opening called the optic fissure which must undergo epithelial fusion (Pai et al., 2012). Failure of optic fissure fusion leads to a congenital blinding disorder called coloboma (Gregory-Evans, 2004). A long standing question pertaining to the mechanism of optic fissure fusion is exactly which ECM remodeling enzymes are actively involved in dismantling the ECM to allow for …

The Developmental And Genetic Basis Of ‘Clubfoot’ In The Peroneal Muscular Atrophy Mutant Mouse, J. Martin Collinson, Nils Lindström, Carlos Neves, Karen Wallace, Caroline Meharg, Rebecca Charles, Zoe Ross, Amy Fraser, Ivan Mbogo, Kadri Oras, Masaru Nakamoto, Simon Barker, Suzanne Duce, Zosia Miedzybrodzka, Neil Vargesson

Biology Faculty Publications

Genetic factors underlying the human limb abnormality congenital talipes equinovarus (‘clubfoot’) remain incompletely understood. The spontaneous autosomal recessive mouse ‘peroneal muscular atrophy’ mutant (PMA) is a faithful morphological model of human clubfoot. In PMA mice, the dorsal (peroneal) branches of the sciatic nerves are absent. In this study, the primary developmental defect was identified as a reduced growth of sciatic nerve lateral motor column (LMC) neurons leading to failure to project to dorsal (peroneal) lower limb muscle blocks. The pma mutation was mapped and a candidate gene encoding LIM-domain kinase 1 (Limk1) identified, which is upregulated in mutant lateral LMC …

Carbohydrate-Based Inducers Of Cellular Stress For Targeting Cancer Cell Metabolism, Fidelis Ndombera

Wayne State University Dissertations

ABSTRACT

CARBOHYDRATE-BASED INDUCERS OF CELLULAR STRESS FOR TARGETING CANCER CELL METABOLISM

by

FIDELIS TOLOYI NDOMBERA

May 2018

Advisor: Dr. Young-Hoon Ahn

Major: Chemistry (Biochemistry)

Degree: Doctor of Philosophy

Metabolic reprogramming and redox control of cancer cells is vital for their proliferation, but also provides selective strategies for treating cancer. Increased generation of reactive oxygen species (ROS) and an intricate control of redox status in cancer cells relative to normal cells provide a basis for designing ROS-inducing anticancer agents. In my work, I designed, synthesized and evaluated carbohydrate-based small molecules for ROS-generation, cytotoxicity and redox signaling and stress response. Our data …

Asymmetric Patterns Of Small Molecule Transport After Nanosecond And Microsecond Electropermeabilization, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier

Bioelectrics Publications

Imaging of fluorescent small molecule transport into electropermeabilized cells reveals polarized patterns of entry, which must reflect in some way the mechanisms of the migration of these molecules across the compromised membrane barrier. In some reports, transport occurs primarily across the areas of the membrane nearest the positive electrode (anode), but in others cathode-facing entry dominates. Here we compare YO-PRO-1, propidium, and calcein uptake into U-937 cells after nanosecond (6 ns) and microsecond (220 µs) electric pulse exposures. Each of the three dyes exhibits a different pattern. Calcein shows no preference for anode- or cathode-facing entry that is detectable with …

Design And Evaluation Of Gemini Surfactant-Based Lipoplexes Modified With Cell-Binding Peptide For Targeted Gene Therapy, Waleed Mohammed-Saeid, Rania Soudy, Richa Tikoo, Kamaljit Kaur, Ronald E. Verrall, Ildiko Badea

Pharmacy Faculty Articles and Research

Purpose Achieving successful gene therapy requires delivery of a gene vector specifically to the targeted tissue with efficient expression and a good safety profile. The objective of this work was to develop, characterize and determine if a novel gemini surfactant-based lipoplex systems, modified with a cancer-targeting peptide p18-4, could serve this role. Methods The targeting peptide p18-4 was either chemically coupled to a gemini surfactant backbone or physically co-formulated with the lipoplexes. The influence of targeting ligand and formulation strategies on essential physicochemical properties of the lipoplexes was evaluated by dynamic light scattering and small angle X-ray scattering techniques. In …

Sivcpz Closely Related To The Ancestral Hiv-1 Is Less Or Non-Pathogenic To Humans In A Hu-Blt Mouse Model, Zhe Yuan, Guobin Kang, Lance Daharsh, Wenjin Fan, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The HIV-1 pandemic is a consequence of the cross-species transmission of simian immunodeficiency virus in wild chimpanzees (SIVcpz) to humans. Our previous study demonstrated SIVcpz strains that are closely related to the ancestral viruses of HIV-1 groups M (SIVcpzMB897) and N (SIVcpzEK505) and two SIVcpz lineages that are not associated with any known HIV-1 infections in humans (SIVcpzMT145 and SIVcpzBF1167), all can readily infect and robustly replicate in the humanized-BLT mouse model of humans. However, the comparative pathogenicity of different SIVcpz strains remains unknown. Herein, we compared the pathogenicity of the above four SIVcpz strains with HIV-1 using humanized-BLT mice. …

Identification Of Unequally Represented Founder Viruses Among Tissues In Very Early Siv Rectal Transmission, Jian Chen, Yanqin Ren, Lance Daharsh, Lu Liu, Guobin Kang, Qingsheng Li, Qiang Wei, Yanmin Wu, Jianqing Xu

Nebraska Center for Virology: Faculty Publications

Characterizing the transmitted/founder (T/F) viruses of multi-variant SIV infection may shed new light on the understanding of mucosal transmission.We intrarectally inoculated six Chinese rhesus macaques with a single high dose of SIVmac251 (3.1 × 10⁴ TCID₅₀) and obtained 985 full-length env sequences from multiple tissues at 6 and 10 days post-infection by single genome amplification (SGA). All 6 monkeys were infected with a range of 2 to 8 T/F viruses and the dominant variants from the inoculum were still dominant in different tissues from each monkey. Interestingly, our data showed that a cluster of rare T/F viruses …

Analytical Performance Of A Low‐Cost Multiplex Polymerase Chain Reaction Human Papillomavirus Genotyping Assay For Use In Sub‐Saharan Africa, Kandali Samwel, Crispin Kahesa, Julius Mwaiselage, Daniela Gonzalez, John T. West, Charles Wood, Joel Palefsky, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

We have tested a multiplex polymerase chain reaction (PCR) human papillomavirus (HPV) genotyping assay to fill the need for rapid and low‐cost HPV detection in Sub‐ Saharan Africa. This method allows high throughput genotyping and simultaneous detection of 14 high‐risk and two low‐risk HPV types, by PCR amplification of HPV DNAs in a single reaction tube. In this study, we describe stepwise experiments to validate the multiplex HPV PCR assay for determination of HPV genotypes from 104 cervical brush samples from Tanzanian women. Assay performance was evaluated by determination of intra‐laboratory reproducibility, sensitivity, and specificity. Further performance was assessed by …

Discovery Of A Non-Nucleoside Rna Polymerase Inhibitor For Blocking Zika Virus Replication Through In Silico Screening, Aryamav Pattnaik, Nicholas Palermo, Bikash R. Sahoo, Zhe Yuan, Duoyi Hu, Arun S. Annamalai, Hiep L. X. Vu, Ignacio Correas, Pavan Kumar Prathipati, Christopher J. Destache, Qingsheng Li, Fernando A. Osorio, Asit K. Pattnaik, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

Zika virus (ZIKV), an emerging arbovirus, has become a major human health concern globally due to its association with congenital abnormalities and neurological diseases. Licensed vaccines or antivirals against ZIKV are currently unavailable. Here, by employing a structure-based approach targeting the ZIKV RNA-dependent RNA polymerase (RdRp), we conducted in silico screening of a library of 100,000 small molecules and tested the top ten lead compounds for their ability to inhibit the virus replication in cell-based in vitro assays. One compound, 3-chloro-N-[({4-[4-(2-thienylcarbonyl)-1-piperazinyl]phenyl}amino)carbonothioyl]-1-benzothiophene-2-carboxamide (TPB), potently inhibited ZIKV replication at submicromolar concentrations. Molecular docking analysis suggests that …

Expression And Function Of Nuclear Receptor Coactivator 4 Isoforms In Transformed Endometriotic And Malignant Ovarian Cells, Stephanie Rockfield, Idhaliz Flores, Meera Nanjundan

Molecular Biosciences Faculty Publications

Iron is proposed to contribute to the transition from endometriosis to specific subtypes of ovarian cancers (OVCAs). Regulation of intracellular iron occurs via a ferritinophagic process involving NCOA4 (Nuclear Receptor Coactivator 4), represented by two major isoforms (NCOA4α and NCOA4β), whose contribution to ovarian cancer biology remains uninvestigated. We thus generated transformed endometriotic cells (via HRAS^V12A, c-MYC^T58A, and p53 inactivation) whose migratory potential was increased in response to conditioned media from senescent endometriotic cells. We identified elevated NCOA4 mRNA in transformed endometriotic cells (relative to non-transformed). Knockdown of NCOA4 increased ferritin heavy chain (FTH1) and p21 …

Mbd2-Cp2c Loop Drives Adult-Type Globin Gene Expression And Definitive Erythropoiesis, Min Young Kim, Ji Sook Kim, Seung Han Son, Chang Su Lim, Hea Young Eum, Dae Hyun Ha, Mi Ae Park, Eun Jung Baek, Buom-Yong Ryu, Ho Chul Kang, Vladimir N. Uversky, Chul Geun Kim

Molecular Biosciences Faculty Publications

During hematopoiesis, red blood cells originate from the hematopoietic stem cell reservoir. Although the regulation of erythropoiesis and globin expression has been intensively investigated, the underlining mechanisms are not fully understood, including the interplay between transcription factors and epigenetic factors. Here, we uncover that the Mbd2-free NuRD chromatin remodeling complex potentiates erythroid differentiation of proerythroblasts via managing functions of the CP2c complexes. We found that both Mbd2 and Mbd3 expression is downregulated during differentiation of MEL cells in vitro and in normal erythropoiesis in mouse bone marrow, and Mbd2 downregulation is crucial for erythropoiesis. In uninduced MEL cells, the Mbd2-NuRD …

Yeast Lifespan Variation Correlates With Cell Growth And Sir2 Expression, Jessica T. Smith, Jill W. White, Huzefa Dungrawala, Hui Hua, Brandt L. Schneider

Molecular Biosciences Faculty Publications

Isogenic wild type yeast cells raised in controlled environments display a significant range of lifespan variation. Recent microfluidic studies suggest that differential growth or gene expression patterns may explain some of the heterogeneity of aging assays. Herein, we sought to complement this work by similarly examining a large set of replicative lifespan data from traditional plate assays. In so doing, we reproduced the finding that short-lived cells tend to arrest at senescence with a budded morphology. Further, we found that wild type cells born unusually small did not have an extended lifespan. However, large birth size and/or high inter-generational growth …

Radx Modulates Rad51 Activity To Control Replication Fork Protection, Kamakoti P. Bhat, Archana Krishnamoorthy, Huzefa Dungrawala, Edwige B. Garcin, Mauro Modesti, David Cortez

Molecular Biosciences Faculty Publications

RAD51 promotes homologous recombination repair (HR) of double-strand breaks and acts during DNA replication to facilitate fork reversal and protect nascent DNA strands from nuclease digestion. Several additional HR proteins regulate fork protection by promoting RAD51 filament formation. Here, we show that RADX modulates stalled fork protection by antagonizing RAD51. Consequently, silencing RADX restores fork protection in cells deficient for BRCA1, BRCA2, FANCA, FANCD2, or BOD1L. Inactivating RADX prevents both MRE11- and DNA2-dependent fork degradation. Furthermore, RADX overexpression causes fork degradation that is dependent on these nucleases and fork reversal. The amount of RAD51 determines the fate of stalled replication …