Medical Anatomy Commons^™

Development Of The Mechanoresponsive Pericellular Matrix Of Chondrons, Donghee Lee, Sydney E. Greer, Andrew T. Dudley

Journal Articles: Genetics, Cell Biology & Anatomy

Physical properties of cartilage are conferred by the composition and ultrastructure of the extracellular matrix. This study focuses on the development of the pericellular matrix (PCM), a domain that directly contacts the chondrocyte and is a key regulator of biomechanical and biochemical signaling. Using three-dimensional cell culture, microfluidic cell compression platforms, and genetic mouse models, we demonstrated that collagen VI is initially assembled at the cell surface and then displaced to form a shell at the PCM-territorial matrix boundary. Cell surface-bound hyaluronan is crucial for the assembly process, and hyaluronan-aggrecan complexes drive displacement. Integrin adhesion is not required early but …

Differential Roles Of Key Brain Regions: Ventral Tegmental Area, Locus Coeruleus, Dorsal Raphe, Nucleus Accumbens, Caudate Nucleus, And Prefrontal Cortex In Regulating Response To Methylphenidate: Insights From Neuronal And Behavioral Studies In Freely Behaving Rats, Nachum Dafny, Catherine Claussen, Emilee Frazier, Yin Liu

Faculty, Staff and Student Publications

A total of 3102 neurons were recorded before and following acute and chronic methylphenidate (MPD) administration. Acute MPD exposure elicits mainly increases in neuronal and behavioral activity in dose–response characteristics. The response to chronic MPD exposure, as compared to acute 0.6, 2.5, or 10.0 mg/kg MPD administration, elicits electrophysiological and behavioral sensitization in some animals and electrophysiological and behavioral tolerance in others when the neuronal recording evaluations were performed based on the animals’ behavioral responses, or amount of locomotor activity, to chronic MPD exposure. The majority of neurons recorded from those expressing behavioral sensitization responded to chronic MPD with further …

Cns-Associated Macrophages Contribute To Intracerebral Aneurysm Pathophysiology, Martina Glavan, Ana Jelic, Damien Levard, Juhana Frösen, Sara Keränen, Bart A A Franx, Ana-Rita Bras, Estelle R Louet, Ádám Dénes, Mario Merlini, Denis Vivien, Marina Rubio

Faculty, Staff and Student Publications

Simple Summary

Vestibular schwannoma (VS), benign cranial nerve sheath tumors of the vestibulocochlear nerve, lack efficacious systemic therapies, especially if they develop in a NF2-related schwannomatosis (NF2) background. They cause hearing loss, tinnitus and balance problems. Metastasis associated in colon cancer 1 (MACC1) is a key driver of metastasis. Although MACC1 expression is associated with highly malignant tumors and VS are considered benign, both are attached to the HGF/MET signaling pathway and MACC1 is a candidate gene localized at a hearing loss-related gene locus. Therefore, it was investigated whether MACC1 might be involved in VS pathogenesis. Surprisingly, MACC1 expression …

Increased Cysteinyl-Trna Synthetase Drives Neuroinflammation In Alzheimer’S Disease, Xiu-Hong Qi, Peng Chen, Yue-Ju Wang, Zhe-Ping Zhou, Xue-Chun Liu, Hui Fang, Chen-Wei Wang, Ji Liu, Rong-Yu Liu, Han-Kui Liu, Zhen-Xin Zhang, Jiang-Ning Zhou

Faculty, Staff and Student Publications

Background

Microglia-mediated neuroinflammation in Alzheimer’s disease (AD) is not only a response to pathophysiological events, but also plays a causative role in neurodegeneration. Cytoplasmic cysteinyl-tRNA synthetase (CARS) is considered to be a stimulant for immune responses to diseases; however, it remains unknown whether CARS is involved in the pathogenesis of AD.

Methods

Postmortem human temporal cortical tissues at different Braak stages and AD patient-derived serum samples were used to investigate the changes of CARS levels in AD by immunocytochemical staining, real-time PCR, western blotting and ELISA. After that, C57BL/6J and APP/PS1 transgenic mice and BV-2 cell line were used to …

Investigation Into Cardiac Myhc-Α 334-352-Specific Tcr Transgenic Mice Reveals A Role For Cytotoxic Cd4 T Cells In The Development Of Cardiac Autoimmunity, Meghna Sur, Mahima T. Rasquinha, Kiruthiga Mone, Chandirasegaran Massilamany, Ninaad Lasrado, Channabasavaiah B. Gurumurthy, Raymond A Sobel, Jay Reddy

Journal Articles: Genetics, Cell Biology & Anatomy

Myocarditis is one of the major causes of heart failure in children and young adults and can lead to dilated cardiomyopathy. Lymphocytic myocarditis could result from autoreactive CD4⁺ and CD8⁺ T cells, but defining antigen specificity in disease pathogenesis is challenging. To address this issue, we generated T cell receptor (TCR) transgenic (Tg) C57BL/6J mice specific to cardiac myosin heavy chain (Myhc)-α 334-352 and found that Myhc-α-specific TCRs were expressed in both CD4⁺ and CD8⁺ T cells. To investigate if the phenotype is more pronounced in a myocarditis-susceptible genetic background, we backcrossed with A/J mice. At …

Targeted Insertion Of Conditional Expression Cassettes Into The Mouse Genome Using The Modified I-Pitt, Hiromi Miura, Ayaka Nakamura, Aki Kurosaki, Ai Kotani, Masaru Motojima, Keiko Tanaka, Shigeru Kakuta, Sanae Ogiwara, Yuhsuke Ohmi, Hirotaka Komaba, Samantha L. P. Schilit, Cynthia C. Morton, Channabasavaiah B. Gurumurthy, Masato Ohtsuka

Journal Articles: Genetics, Cell Biology & Anatomy

BACKGROUND: Transgenic (Tg) mice are widely used in biomedical research, and they are typically generated by injecting transgenic DNA cassettes into pronuclei of one-cell stage zygotes. Such animals often show unreliable expression of the transgenic DNA, one of the major reasons for which is random insertion of the transgenes. We previously developed a method called "pronuclear injection-based targeted transgenesis" (PITT), in which DNA constructs are directed to insert at pre-designated genomic loci. PITT was achieved by pre-installing so called landing pad sequences (such as heterotypic LoxP sites or attP sites) to create seed mice and then injecting Cre recombinase or …

Synaptic Vesicle Dynamics In Mouse Rod Bipolar Cells, Sara S Patterson, Rebecca J Girresch, Marcus A Mazzaferri, Andrea S Bordt, Wendy L Piñon-Teal, Brett D Jesse, Dinukie-Chantal W Perera, Melanie A Schlepphorst, James A Kuchenbecker, Alice Z Chuang, Jay Neitz, David W Marshak, Judith Mosinger Ogilvie

Faculty, Staff and Student Publications

Considerable progress has been made in studying the receptive fields of the most common primate retinal ganglion cell (RGC) types, such as parasol RGCs. Much less is known about the rarer primate RGC types and the circuitry that gives rise to noncanonical receptive field structures. The goal of this study was to analyze synaptic inputs to smooth monostratified RGCs to determine the origins of their complex spatial receptive fields, which contain isolated regions of high sensitivity called "hotspots." Interestingly, smooth monostratified RGCs co-stratify with the well-studied parasol RGCs and are thus constrained to receiving input from bipolar and amacrine cells …

Structures Of Channelrhodopsin Paralogs In Peptidiscs Explain Their Contrasting K+ And Na+ Selectivities, Shu Kikuta, Shin Nagayama, Sanae Hasegawa-Ishii

Faculty, Staff and Student Publications

The olfactory epithelium (OE) is directly exposed to environmental agents entering the nasal cavity, leaving OSNs prone to injury and degeneration. The causes of olfactory dysfunction are diverse and include head trauma, neurodegenerative diseases, and aging, but the main causes are chronic rhinosinusitis (CRS) and viral infections. In CRS and viral infections, reduced airflow due to local inflammation, inflammatory cytokine production, release of degranulated proteins from eosinophils, and cell injury lead to decreased olfactory function. It is well known that injury-induced loss of mature OSNs in the adult OE causes massive regeneration of new OSNs within a few months through …

Anesthetized Animal Experiments For Neuroscience Research, Shin Nagayama, Sanae Hasegawa-Ishii, Shu Kikuta

Faculty, Staff and Student Publications

Brain research has progressed with anesthetized animal experiments for a long time. Recent progress in research techniques allows us to measure neuronal activity in awake animals combined with behavioral tasks. The trends became more prominent in the last decade. This new research style triggers the paradigm shift in the research of brain science, and new insights into brain function have been revealed. It is reasonable to consider that awake animal experiments are more ideal for understanding naturalistic brain function than anesthetized ones. However, the anesthetized animal experiment still has advantages in some experiments. To take advantage of the anesthetized animal …

Dopamine, Norepinephrine And Serotonin Participate Differently In Methylphenidate Action In Concomitant Behavioral And Ventral Tegmental Area, Locus Coeruleus And Dorsal Raphe Neuronal Study In Young Rats, Cruz Reyes-Vasquez, Zachary Jones, Bin Tang, Nachum Dafny

Faculty, Staff and Student Publications

Methylphenidate (MPD), known as Ritalin, is a psychostimulant used to treat children, adults, and the elderly. MPD exerts its effects through increasing concentrations of dopamine (DA), norepinephrine (NE), and serotonin (5-HT) in the synaptic cleft. Concomitant behavioral and neuronal recording from the ventral tegmental area (VTA), locus coeruleus (LC), and from the dorsal raphe (DR) nucleus, which are the sources of DA, NE, and 5-HT to the mesocorticolimbic circuit, were investigated following acute and repetitive (chronic) saline, 0.6, 2.5, or 10.0 mg/kg MPD. Animals received daily saline or MPD administration on experimental days 1 to 6 (ED1–6), followed by a …

Enhanced Presynaptic Mitochondrial Energy Production Is Required For Memory Formation, Erica L Underwood, John B Redell, Kimberly N Hood, Mark E Maynard, Michael Hylin, M Neal Waxham, Jing Zhao, Anthony N Moore, Pramod K Dash

Faculty, Staff and Student Publications

Some of the prominent features of long-term memory formation include protein synthesis, gene expression, enhanced neurotransmitter release, increased excitability, and formation of new synapses. As these processes are critically dependent on mitochondrial function, we hypothesized that increased mitochondrial respiration and dynamics would play a prominent role in memory formation. To address this possibility, we measured mitochondrial oxygen consumption (OCR) in hippocampal tissue punches from trained and untrained animals. Our results show that context fear training significantly increased basal, ATP synthesis-linked, and maximal OCR in the Shaffer collateral-CA1 synaptic region, but not in the CA1 cell body layer. These changes were …

Acute Acat1/Soat1 Blockade Increases Mam Cholesterol And Strengthens Er-Mitochondria Connectivity., Taylor C Harned, Radu V Stan, Ze Cao, Rajarshi Chakrabarti, Henry N Higgs, Catherine C Y Chang, Ta Yuan Chang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Cholesterol is a key component of all mammalian cell membranes. Disruptions in cholesterol metabolism have been observed in the context of various diseases, including neurodegenerative disorders such as Alzheimer's disease (AD). The genetic and pharmacological blockade of acyl-CoA:cholesterol acyltransferase 1/sterol O-acyltransferase 1 (ACAT1/SOAT1), a cholesterol storage enzyme found on the endoplasmic reticulum (ER) and enriched at the mitochondria-associated ER membrane (MAM), has been shown to reduce amyloid pathology and rescue cognitive deficits in mouse models of AD. Additionally, blocking ACAT1/SOAT1 activity stimulates autophagy and lysosomal biogenesis; however, the exact molecular connection between the ACAT1/SOAT1 blockade and these observed benefits remain …

Positioning The Brainstem Within The Neural Network Of Threat Prediction, Xu O Zhang, Fabricio H Do Monte

Faculty, Staff and Student Publications

In a recent study, Strickland and McDannald dissected the role of brainstem networks in threat prediction. Using probabilistic threat discrimination in rats, the authors demonstrated that brainstem neurons estimate threat probability and generate positive aversive prediction errors after unexpected outcomes. Their findings suggest that, beyond organizing defensive behaviors, brainstem neurons are involved in threat prediction computations.

Trogocytosis Of Neurons And Glial Cells By Microglia In A Healthy Adult Macaque Retina, Megan Goyal, Andrea S Bordt, Jay Neitz, David W Marshak

Faculty, Staff and Student Publications

Microglial cells are the primary resident immune cells in the retina. In healthy adults, they are ramified; that is, they have extensive processes that move continually. In adult retinas, microglia maintain the normal structure and function of neurons and other glial cells, but the mechanism underlying this process is not well-understood. In the mouse hippocampus, microglia engulf small pieces of axons and presynaptic terminals via a process called trogocytosis. Here we report that microglia in the adult macaque retina also engulf pieces of neurons and glial cells, but not at sites of synapses. We analyzed microglia in a volume of …

Synaptic Origins Of The Complex Receptive Field Structure In Primate Smooth Monostratified Retinal Ganglion Cells, Andrea S Bordt, Sara S Patterson, James A Kuchenbecker, Marcus A Mazzaferri, Joel N Yearick, Emma R Yang, Judith Mosinger Ogilvie, Jay Neitz, David W Marshak

Faculty, Staff and Student Publications

Ganglion cells are the projection neurons of the retina. Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin and also receive input from rods and cones via bipolar cells and amacrine cells. In primates, multiple types of ipRGCs have been identified. The ipRGCs with somas in the ganglion cell layer have been studied extensively, but less is known about those with somas in the inner nuclear layer, the "displaced" cells. To investigate their synaptic inputs, three sets of horizontal, ultrathin sections through central macaque retina were collected using serial block-face scanning electron microscopy. One displaced ipRGC received nearly all …

Adipose Tissue-Specific Ablation Of Ces1d Causes Metabolic Dysregulation In Mice, Gang Li, Xin Li, Li Yang, Shuyue Wang, Yulin Dai, Baharan Fekry, Lucas Veillon, Lin Tan, Rebecca Berdeaux, Kristin Eckel-Mahan, Philip L Lorenzi, Zhongming Zhao, Richard Lehner, Kai Sun

Faculty, Staff and Student Publications

Carboxylesterase 1d (Ces1d) is a crucial enzyme with a wide range of activities in multiple tissues. It has been reported to localize predominantly in ER. Here, we found that Ces1d levels are significantly increased in obese patients with type 2 diabetes. Intriguingly, a high level of Ces1d translocates onto lipid droplets where it digests the lipids to produce a unique set of fatty acids. We further revealed that adipose tissue-specific Ces1d knock-out (FKO) mice gained more body weight with increased fat mass during a high fat-diet challenge. The FKO mice exhibited impaired glucose and lipid metabolism and developed exacerbated liver …

Altered Genome-Wide Hippocampal Gene Expression Profiles Following Early Life Lead Exposure And Their Potential For Reversal By Environmental Enrichment, Garima Singh, V Singh, T Kim, A Ertel, W Fu, J S Schneider

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Early life lead (Pb) exposure is detrimental to neurobehavioral development. The quality of the environment can modify negative influences from Pb exposure, impacting the developmental trajectory following Pb exposure. Little is known about the molecular underpinnings in the brain of the interaction between Pb and the quality of the environment. We examined relationships between early life Pb exposure and living in an enriched versus a non-enriched postnatal environment on genome-wide transcription profiles in hippocampus CA1. RNA-seq identified differences in the transcriptome of enriched vs. non-enriched Pb-exposed animals. Most of the gene expression changes associated with Pb exposure were reversed by …

A Mathematical Model Of Glut1 Modulation In Rods And Rpe And Its Differential Impact In Cell Metabolism, Andrea Aparicio, Erika T Camacho, Nancy J. Philp, Stephen A Wirkus

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

We present a mathematical model of key glucose metabolic pathways in two cells of the human retina: the rods and the retinal pigmented epithelium (RPE). Computational simulations of glucose transporter 1 (GLUT1) inhibition in the model accurately reproduce experimental data from conditional knockout mice and reveal that modification of GLUT1 expression levels of both cells differentially impacts their metabolism. We hypothesize that, under glucose scarcity, the RPE’s energy producing pathways are altered in order to preserve its functionality, impacting the photoreceptors’ outer segment renewal. On the other hand, when glucose is limited in the rods, aerobic glycolysis is preserved, which …

Computational Analysis Of Memory Consolidation Following Inhibitory Avoidance (Ia) Training In Adult And Infant Rats: Critical Roles Of Camkiia And Mecp2, Yili Zhang, Paul Smolen, Cristina M Alberini, Douglas A Baxter, John H Byrne

Faculty, Staff and Student Publications

Key features of long-term memory (LTM), such as its stability and persistence, are acquired during processes collectively referred to as consolidation. The dynamics of biological changes during consolidation are complex. In adult rodents, consolidation exhibits distinct periods during which the engram is more or less resistant to disruption. Moreover, the ability to consolidate memories differs during developmental periods. Although the molecular mechanisms underlying consolidation are poorly understood, the initial stages rely on interacting signaling pathways that regulate gene expression, including brain-derived neurotrophic factor (BDNF) and Ca²⁺/calmodulin-dependent protein kinase II α (CaMKIIα) dependent feedback loops. We investigated the ways …

Patterns Of Crystallin Gene Expression In Differentiation State Specific Regions Of The Embryonic Chicken Lens, Zhiwei Ma, Daniel Chauss, Joshua Disatham, Xiaodong Jiao, Lisa Ann Brennan, A Sue Menko, Marc Kantorow, J Fielding Hejtmancik

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Purpose: Transition from lens epithelial cells to lens fiber cell is accompanied by numerous changes in gene expression critical for lens transparency. We identify expression patterns of highly prevalent genes including ubiquitous and enzyme crystallins in the embryonic day 13 chicken lens.

Methods: Embryonic day 13 chicken lenses were dissected into central epithelial cell (EC), equatorial epithelial cell (EQ), cortical fiber cell (FP), and nuclear fiber cell (FC) compartments. Total RNA was prepared, subjected to high-throughput unidirectional mRNA sequencing, analyzed, mapped to the chicken genome, and functionally grouped.

Results: A total of 77,097 gene-specific transcripts covering 17,450 genes were expressed, …

Uncontrolled Mitochondrial Calcium Uptake Underlies The Pathogenesis Of Neurodegeneration In Micu1-Deficient Mice And Patients, Raghavendra Singh, Adam Bartok, Melanie Paillard, Ashley L. Tyburski, Melanie B Elliott, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Dysregulation of mitochondrial Ca2+ homeostasis has been linked to neurodegenerative diseases. Mitochondrial Ca2+ uptake is mediated via the calcium uniporter complex that is primarily regulated by MICU1, a Ca2+-sensing gatekeeper. Recently, human patients with MICU1 loss-of-function mutations were diagnosed with neuromuscular and cognitive impairments. While studies in patient-derived cells revealed altered mitochondrial calcium signaling, the neuronal pathogenesis was difficult to study. To fill this void, we created a neuron-specific MICU1-KO mouse model. These animals show progressive, abnormal motor and cognitive phenotypes likely caused by the degeneration of motor neurons in the spinal cord and the cortex. We found increased susceptibility …

A Crispr Toolbox For Generating Intersectional Genetic Mouse Models For Functional, Molecular, And Anatomical Circuit Mapping, Savannah J Lusk, Andrew Mckinney, Patrick J Hunt, Paul G Fahey, Jay Patel, Andersen Chang, Jenny J Sun, Vena K Martinez, Ping Jun Zhu, Jeremy R Egbert, Genevera Allen, Xiaolong Jiang, Benjamin R Arenkiel, Andreas S Tolias, Mauro Costa-Mattioli, Russell S Ray

Faculty, Staff and Students Publications

BACKGROUND: The functional understanding of genetic interaction networks and cellular mechanisms governing health and disease requires the dissection, and multifaceted study, of discrete cell subtypes in developing and adult animal models. Recombinase-driven expression of transgenic effector alleles represents a significant and powerful approach to delineate cell populations for functional, molecular, and anatomical studies. In addition to single recombinase systems, the expression of two recombinases in distinct, but partially overlapping, populations allows for more defined target expression. Although the application of this method is becoming increasingly popular, its experimental implementation has been broadly restricted to manipulations of a limited set of …

Mintruls: Prediction Of Mirna-Mrna Target Site Interactions Using Regularized Least Square Method, Sushil Kumar Shakyawar, Siddesh Southekal, Chittibabu Guda

Journal Articles: Genetics, Cell Biology & Anatomy

Identification of miRNA-mRNA interactions is critical to understand the new paradigms in gene regulation. Existing methods show suboptimal performance owing to inappropriate feature selection and limited integration of intuitive biological features of both miRNAs and mRNAs. The present regularized least square-based method, mintRULS, employs features of miRNAs and their target sites using pairwise similarity metrics based on free energy, sequence and repeat identities, and target site accessibility to predict miRNA-target site interactions. We hypothesized that miRNAs sharing similar structural and functional features are more likely to target the same mRNA, and conversely, mRNAs with similar features can be targeted by …

Uveitis-Mediated Immune Cell Invasion Through The Extracellular Matrix Of The Lens Capsule, Jodirae Dedreu, Sonali Pal-Ghosh, Mary J Mattapallil, Rachel R Caspi, Mary Ann Stepp, A Sue Menko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

While the eye is considered an immune privileged site, its privilege is abrogated when immune cells are recruited from the surrounding vasculature in response to trauma, infection, aging, and autoimmune diseases like uveitis. Here, we investigate whether in uveitis immune cells become associated with the lens capsule and compromise its privilege in studies of C57BL/6J mice with experimental autoimmune uveitis. These studies show that at D14, the peak of uveitis in these mice, T cells, macrophages, and Ly6G/Ly6C+ immune cells associate with the lens basement membrane capsule, burrow into the capsule matrix, and remain integrated with the capsule as immune …

Tfeb Regulates Murine Liver Cell Fate During Development And Regeneration, Nunzia Pastore, Tuong Huynh, Niculin J Herz, Alessia Calcagni', Tiemo J Klisch, Lorenzo Brunetti, Kangho Ho Kim, Marco De Giorgi, Ayrea Hurley, Annamaria Carissimo, Margherita Mutarelli, Niya Aleksieva, Luca D'Orsi, William R Lagor, David D Moore, Carmine Settembre, Milton J Finegold, Stuart J Forbes, Andrea Ballabio

Faculty, Staff and Students Publications

It is well established that pluripotent stem cells in fetal and postnatal liver (LPCs) can differentiate into both hepatocytes and cholangiocytes. However, the signaling pathways implicated in the differentiation of LPCs are still incompletely understood. Transcription Factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy, is known to be involved in osteoblast and myeloid differentiation, but its role in lineage commitment in the liver has not been investigated. Here we show that during development and upon regeneration TFEB drives the differentiation status of murine LPCs into the progenitor/cholangiocyte lineage while inhibiting hepatocyte differentiation. Genetic interaction studies show that …

Sooty Mangabey Genome Sequence Provides Insight Into Aids Resistance In A Natural Siv Host, David Palesch, Steven E. Bosinger, Gregory K. Tharp, Thomas H. Vanderford, Mirko Paiardini, Ann Chahroudi, Zachary P. Johnson, Frank Kirchhoff, Beatrice H. Hahn, Robert B. Norgren, Nirav B. Patel, Donald L. Sodora, Reem A. Dawoud, Caro-Beth Stewart, Sara M. Seepo, R. Alan Harris, Yue Liu, Muthuswamy Raveendran, Yi Han, Adam English, Gregg W.C. Thomas, Matthew W. Hahn, Lenore Pipes, Christopher E. Mason, Donna M. Muzny, Richard A. Gibbs, Daniel Sauter, Kim Worley, Jeffrey Rogers, Guido Silvestri

Journal Articles: Genetics, Cell Biology & Anatomy

In contrast to infections with human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in macaques, SIV infection of a natural host, sooty mangabeys (Cercocebus atys), is non-pathogenic despite high viraemia. Here we sequenced and assembled the genome of a captive sooty mangabey. We conducted genome-wide comparative analyses of transcript assemblies from C. atys and AIDS-susceptible species, such as humans and macaques, to identify candidates for host genetic factors that influence susceptibility. We identified several immune-related genes in the genome of C. atys that show substantial sequence divergence from macaques or humans. One of these sequence divergences, a …

Exome Screening To Identify Loss-Of-Function Mutations In The Rhesus Macaque For Development Of Preclinical Models Of Human Disease, Adam Cornish, Robert M. Gibbs, Robert B. Norgren

Journal Articles: Genetics, Cell Biology & Anatomy

BACKGROUND: Exome sequencing has been utilized to identify genetic variants associated with disease in humans. Identification of loss-of-function mutations with exome sequencing in rhesus macaques (Macaca mulatta) could lead to valuable animal models of genetic disease. Attempts have been made to identify variants in rhesus macaques by aligning exome data against the rheMac2 draft genome. However, such efforts have been impaired due to the incompleteness and annotation errors associated with rheMac2. We wished to determine whether aligning exome reads against our new, improved rhesus genome, MacaM, could be used to identify high impact, loss-of-function mutations in rhesus macaques that would …

Gonad: Genome-Editing Via Oviductal Nucleic Acids Delivery System: A Novel Microinjection Independent Genome Engineering Method In Mice., Gou Takahashi, Channabasavaiah B. Gurumurthy, Kenta Wada, Hiromi Miura, Masahiro Sato, Masato Ohtsuka

Journal Articles: Genetics, Cell Biology & Anatomy

Microinjection is considered the gold standard technique for delivery of nucleic acids (NAs; transgenes or genome editing tools such as CRISPR/Cas9 systems) into embryos, for creating genetically modified organisms. It requires sophisticated equipment as well as well-trained and highly skilled personnel to perform the micro-injection technique. Here, we describe a novel and simple microinjection-independent technique, called Genome-editing via Oviductal Nucleic Acids Delivery (GONAD). Using GONAD, we show that NAs (e.g., eGFP mRNA or Cas9 mRNA/sgRNAs) can be effectively delivered to pre-implantation embryos within the intact mouse oviduct by a simple electroporation method, and result in the desired genetic modification in …

One-Step Generation Of Multiple Transgenic Mouse Lines Using An Improved Pronuclear Injection-Based Targeted Transgenesis (I-Pitt)., Masato Ohtsuka, Hiromi Miura, Keiji Mochida, Michiko Hirose, Ayumi Hasegawa, Atsuo Ogura, Ryuta Mizutani, Minoru Kimura, Ayako Isotani, Masahito Ikawa, Masahiro Sato, Channabasavaiah B. Gurumurthy

Journal Articles: Genetics, Cell Biology & Anatomy

BACKGROUND: The pronuclear injection (PI) is the simplest and widely used method to generate transgenic (Tg) mice. Unfortunately, PI-based Tg mice show uncertain transgene expression due to random transgene insertion in the genome, usually with multiple copies. Thus, typically at least three or more Tg lines are produced by injecting over 200 zygotes and the best line/s among them are selected through laborious screening steps. Recently, we developed technologies using Cre-loxP system that allow targeted insertion of single-copy transgene into a predetermined locus through PI. We termed the method as PI-based Targeted Transgenesis (PITT). A similar method using PhiC31-attP/B system …

Assessment Of Artificial Mirna Architectures For Higher Knockdown Efficiencies Without The Undesired Effects In Mice., Hiromi Miura, Hidetoshi Inoko, Masafumi Tanaka, Hirofumi Nakaoka, Minoru Kimura, Channabasavaiah B. Gurumurthy, Masahiro Sato, Masato Ohtsuka

Journal Articles: Genetics, Cell Biology & Anatomy

RNAi-based strategies have been used for hypomorphic analyses. However, there are technical challenges to achieve robust, reproducible knockdown effect. Here we examined the artificial microRNA (amiRNA) architectures that could provide higher knockdown efficiencies. Using transient and stable transfection assays in cells, we found that simple amiRNA-expression cassettes, that did not contain a marker gene (-MG), displayed higher amiRNA expression and more efficient knockdown than those that contained a marker gene (+MG). Further, we tested this phenomenon in vivo, by analyzing amiRNA-expressing mice that were produced by the pronuclear injection-based targeted transgenesis (PITT) method. While we observed significant silencing of the …