Medical Sciences Commons^™

Defining The Role Of Il-15 Trans-Presentation By Distinct Cell-Types During The Development And Homeostasis Of Natural Killer And Invariant Natural Killer T Cells, Eliseo F. Castillo

Dissertations and Theses (Open Access)

The immuno-regulatory functions displayed by NK and iNKT cells have highlighted their importance as key lymphocytes involved in innate and adaptive immunity. Therefore, understanding the dynamics influencing the generation of NK and iNKT cells is extremely important. IL-15 has been shown to provide a critical signal throughout the development and homeostasis of NK and iNKT cells; however, the cellular source of IL-15 has remained unclear. In this investigation, I provide evidence that the cell-type providing IL-15 to NK and iNKT cells via trans-presentation is determined by the tissue site and the maturation status of NK and iNKT cells. For NK …

Immune Recognition Of Self Nucleic Acids Driven By Endogenous Antimicrobial Peptides: Role In Autoimmunity, Dipyaman Ganguly

Dissertations and Theses (Open Access)

Innate immune recognition of extracellular host-derived self-DNA and self-RNA is prevented by endosomal seclusion of the Toll-like receptors (TLRs) in the dendritic cells (DCs). However, in psoriasis plasmacytoid dendritic cells have been found to be able to sense self-DNA molecules in complex with the endogenous cationic antimicrobial peptide LL37, which are internalized into the endosomal compartments and thus can access TLR9. We investigated whether this endogenous peptide can also interact with extracellular self-RNA and lead to DC activation. We found that LL37 binds self-RNA as well as self-DNA going into an electrostatic interaction; forms micro-aggregates of nano-scale particles protected from …

Cip4 And Src In Promoting The Migration And Invasion Of Breast Cancers, Christina S. Pichot

Dissertations and Theses (Open Access)

Cellular invasion represents a critical early step in the metastatic cascade, and many proteins have been identified as part of an “invasive signature.” The non-receptor tyrosine kinase Src is commonly upregulated in breast cancers, often in conjunction with overexpression of EGFR. Signaling from this pathway stimulates cell proliferation, migration, and invasion and frequently involves proteins that regulate the cytoskeleton. My data demonstrates that inhibition of Src, using the small-molecule inhibitor dasatinib, impairs cellular migration and invasion. Furthermore, Src inhibition sensitizes the cells to the effects of the chemotherapeutic doxorubicin resulting in dramatic, synergistic inhibition of proliferation with combination treatments. The …

Role Of All Of The Prrsv Glycoproteins In Protective Immune Response, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Porcine reproductive and respiratory syndrome virus (PRRSV) contains the major glycoprotein, GP5, as well as three other minor glycoproteins, namely, GP2a, GP3, and GP4, on the virion envelope, all of which are required for generation of infectious virions. To study their interactions amongst each other and with the cellular receptor for PRRSV, we have cloned each of the viral glycoproteins and CD163 receptor in expression vectors and examined their expression and interaction with each other in transfected cells by co-immunoprecipitation (co-IP) assay using monospecific antibodies. Our results show that strong interaction exists between GP4 and GP5 proteins, although weak interactions …

Cell-Type Specific Distribution Of Chloride Transporters In The Rat Suprachiasmatic Nucleus, Michael A. Belenky, Patricia J. Sollars, David B. Mount, Seth L. Alper, Yosef Yarom, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

The suprachiasmatic nucleus (SCN) is a circadian oscillator and biological clock. Cell-to-cell communication is important for synchronization among SCN neuronal oscillators and the great majority of SCN neurons use γ-aminobutyric acid (GABA) as a neurotransmitter, the principal inhibitory neurotransmitter in the adult central nervous system. Acting via the ionotropic GABAA receptor, a chloride ion channel, GABA typically evokes inhibitory responses in neurons via Cl− influx. Within the SCN GABA evokes both inhibitory and excitatory responses although the mechanism underlying GABA-evoked excitation in the SCN is unknown. GABA-evoked depolarization in immature neurons in several regions of the brain is a function …

Porcine Reproductive And Respiratory Syndrome Virus Nonstructural Protein 1Β Modulates Host Innate Immune Response By Antagonizing Irf3 Activation, Lalit Beura, Saumendra Sarkar, Byungjoon Kwon, Sakthivel Subramaniam, Clinton J. Jones, Asit K. Pattnaik, Fernando A. Osorio

School of Veterinary and Biomedical Sciences: Faculty Publications

Porcine reproductive and respiratory syndrome virus (PRRSV) infection of swine leads to a serious disease characterized by a delayed and defective adaptive immune response. It is hypothesized that a suboptimal innate immune response is responsible for the disease pathogenesis. In the study presented here we tested this hypothesis and identified several nonstructural proteins (NSPs) with innate immune evasion properties encoded by the PRRS viral genome. Four of the total ten PRRSV NSPs tested were found to have strong to moderate inhibitory effects on beta interferon (IFN-β) promoter activation. The strongest inhibitory effect was exhibited by NSP1 followed by, NSP2, NSP11, …

The Minor Envelope Glycoproteins Gp2a And Gp4 Of Porcine Reproductive And Respiratory Syndrome Virus Interact With The Receptor Cd163, Phani B. Das, Phat X. Dinh, Israrul H. Ansari, Marcelo De Lima, Fernando A. Osorio, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Porcine reproductive and respiratory syndrome virus (PRRSV) contains the major glycoprotein, GP5, as well as three other minor glycoproteins, namely, GP2a, GP3, and GP4, on the virion envelope, all of which are required for generation of infectious virions. To study their interactions with each other and with the cellular receptor for PRRSV, we have cloned each of the viral glycoproteins and CD163 receptor in expression vectors and examined their expression and interaction with each other in transfected cells by coimmunoprecipitation (co-IP) assay using monospecific antibodies. Our results show that a strong interaction exists between the GP4 and GP5 proteins, although …

Neuroaids In Africa, Kevin Robertson, Jeff Liner, James Hakim, Jean-Louis Sankalé, Igor Grant, Scott Letendre, David Clifford, Amadou Gallo Diop, Assan Jaye, Georgette Kanmogne, Alfred Njamnshi, T. Dianne Langford, Tufa Gemechu Weyessa, Charles Wood, Mwanza Banda, Mina Hosseinipour, Ned Sacktor, Noeline Nakasuja, Paul Bangirana, Robert Paul, John Joska, Joseph Wong, Michael Boivin, Penny Holding, Betsy Kammerer, Annelies Van Rie, Prudence Ive, Avindra Nath, Kathy Lawler, Clement Adebamowo, Walter Royal Iii, Jeymohan Joseph

Nebraska Center for Virology: Faculty Publications

In July 2009, the Center for Mental Health Research on AIDS at the National Institute of Mental Health organized and supported the meeting “NeuroAIDS in Africa.” This meeting was held in Cape Town, South Africa, and was affiliated with the 5th IAS Conference on HIV Pathogenesis, Treatment and Prevention. Presentations began with an overview of the epidemiology of HIV in sub-Saharan Africa, the molecular epidemiology of HIV, HIV-associated neurocognitive disorders (HANDs), and HAND treatment. These introductory talks were followed by presentations on HAND research and clinical care in Botswana, Cameroon, Ethiopia, The Gambia, Kenya, Malawi, Nigeria, Senegal, South Africa, Uganda, …

Functional Properties Of The Hiv-1 Subtype C Envelope Glycoprotein Associated With Mother-To-Child Transmission, Hong Zhang, Marzena Rola, John T. West, Damien C. Tully, Piotr Kubis, Jun He, Chipepo Kankasa, Charles Wood

Nebraska Center for Virology: Faculty Publications

Understanding the properties of viruses capable of establishing infection during perinatal transmission of HIV-1 is critical for designing effective means of limiting transmission. We previously demonstrated that the newly transmitted viruses (in infant) were more fit in growth, as imparted by their envelope glycoproteins, than those in their corresponding mothers. Here, we further characterized the viral envelope glycoproteins from six mother-infant transmission pairs and determined whether any specific envelope functions correlate with HIV-1 subtype C perinatal transmission. We found that most newly transmitted viruses were less susceptible to neutralization by their maternal plasma compared to contemporaneous maternal viruses. However, the …

Chronology And Evolution Of The Hiv-1 Subtype C Epidemic In Ethiopia, Damien C. Tully, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective—To reconstruct the onset date and evolutionary history of the HIV-1 subtype C epidemic in Ethiopia - one of the earliest recorded subtype C epidemics in the world.

Design—HIV-1 C env sequences with a known sampling year isolated from HIV-1 positive patients from Ethiopia between 1984 and 2003.

Methods—Evolutionary parameters including origin and demographic growth patterns were estimated using a Bayesian coalescent-based approach under either strict or relaxed molecular clock models.

Results—Bayesian evolutionary analysis indicated a most recent common ancestor date of 1965 with three distinct epidemic growth phases. Regression analysis of root-to-tip distances revealed a highly similar estimate for …

Induction Of Interferon And Interferon Signaling Pathways By Replication Of Defective Interfering Particle Rna In Cells Constitutively Expressing Vesicular Stomatitis Virus Replication Proteins, Debasis Panda, Phat X. Dinh, Lalit Beura, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

We show here that replication of defective interfering (DI) particle RNA in HEK293 cells stably expressing vesicular stomatitis virus (VSV) replication proteins potently activates interferon (IFN) and IFN signaling pathways through upregulation of IFN- promoter, IFN-stimulated response element (ISRE) promoter, and NF-κB promoter activities. Replication of DI particle RNA, not mere expression of the viral replication proteins, was found to be critical for induction of IFN and IFN signaling. The stable cells supporting replication of DI RNA described in this report will be useful in further examining the innate immune signaling pathways and the host cell functions in viral genome …

Towards An Understanding Of The Herpes Simplex Virus Type 1 Latency-Reactivation Cycle, Guey-Chuen Perng, Clinton Jones

School of Veterinary and Biomedical Sciences: Faculty Publications

Infection by herpes simplex virus type 1 (HSV-1) can cause clinical symptoms in the peripheral and central nervous system. Recurrent ocular shedding can lead to corneal scarring and vision loss making HSV-1 a leading cause of corneal blindness due to an infectious agent. The primary site of HSV-1 latency is sensory neurons within trigeminal ganglia. Periodically, reactivation from latency occurs resulting in virus transmission and recurrent disease. During latency, the latency-associated transcript (LAT) is abundantly expressed. LAT expression is important for the latency-reactivation cycle in animal models, in part, because it inhibits apoptosis, viral gene expression, and productive infection. A …

Enhancement Of Autophagy During Lytic Replication By The Kaposi’S Sarcoma-Associated Herpesvirus Replication And Transcription Activator, Hui-Ju Wen, Zhilong Yang, You Zhou, Charles Wood

Nebraska Center for Virology: Faculty Publications

Autophagy is one of two major degradation systems in eukaryotic cells. The degradation mechanism of autophagy is required to maintain the balance between the biosynthetic and catabolic processes and also contributes to defense against invading pathogens. Recent studies suggest that a number of viruses can evade or subvert the host cell autophagic pathway to enhance their own replication. Here, we investigated the effect of autophagy on the KSHV (Kaposi’s sarcoma-associated herpesvirus) life cycle. We found that the inhibition of autophagy reduces KSHV lytic reactivation from latency, and an enhancement of autophagy can be detected during KSHV lytic replication. In addition, …

Chlorella Viruses Encode Most, If Not All, Of The Machinery To Glycosylate Their Glycoproteins Independent Of The Endoplasmic Reticulum And Golgi, James L. Van Etten, James Gurnon, Giane M. Yanai-Balser, David Dunigan, Michael V. Graves

Nebraska Center for Virology: Faculty Publications

In contrast to all other viruses that use the host machinery located in the endoplasmic reticulum and Golgi to glycosylate their glycoproteins, the large dsDNA-containing chlorella viruses encode most, if not all, of the components to glycosylate their major capsid proteins. Furthermore, all experimental results indicate that glycosylation occurs independent of the endoplasmic reticulum and Golgi. (Review article)

Regulation Of Apoptotic Effects Of Erythrocarpine E, A New Cytotoxic Limonoid Extracted From Chisocheton Erythrocarpus., Norliza Shah Jehan Muttiah

Student Works (2010-2019)

The aim of this study is to determine the cytotoxic and apoptotic effects of erythrocarpine E (CEB4), a new limonoid extracted from Chisocheton erythrocarpus. MTT assay, Live/Dead® Viability/Cytotoxicity assay, cell cycle analysis, annexin V analysis, PARP cleavage analysis, DNA fragmentation assay, sandwich ELISA assay and Western blot analysis were performed on five CEB4 treated cancer cell lines; HSC4COX2- and HSC2 (oral), CaSki (cervical), HepG2 (liver), MCF7 (breast) and NHBE (normal human bronchial epithelial cell line). CEB4 treated HSC4COX2-, HSC2, CaSki, HepG2 and MCF7 cells demonstrated a cytotoxic effect and inhibited cell proliferation in a dose and time dependent manner. CEB4 …

Method For Identification Of Virulence Determinants, Raul G. Barletta, Beth Harris

School of Veterinary and Biomedical Sciences: Faculty Publications

Disclosed are methods for the determination of virulence determinants in bacteria and in particular bacteria of the genus Mycobacterium. Also disclosed are compositions and methods for stimulating an immune response in an animal using bacteria and virulence determinants identified by the methods of the present invention.

Chemosensitization Of Cancer Cells By Sirna Using Targeted Nanogel Delivery, Erin B. Dickerson, William H. Blackburn, Michael H. Smith, Laura B. Kapa, L. Andrew Lyon, John F. Mcdonald

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background: Chemoresistance is a major obstacle in cancer treatment. Targeted therapies that enhance cancer cell sensitivity to chemotherapeutic agents have the potential to increase drug efficacy while reducing toxic effects on untargeted cells. Targeted cancer therapy by RNA interference (RNAi) is a relatively new approach that can be used to reversibly silence genes in vivo by selectively targeting genes such as the epidermal growth factor receptor (EGFR), which has been shown to increase the sensitivity of cancer cells to taxane chemotherapy. However, delivery represents the main hurdle for the broad development of RNAi therapeutics.

Methods: We report here …

Methods And Compositions For Vaccnation Of Animals With Prrsv Antigens With Improved Immunogenicity, Israrul H. Ansari, Fernando A. Osorio, Asit K. Pattnaik,

School of Veterinary and Biomedical Sciences: Faculty Publications

Pigs challenged with hypoglycosylated variants of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) major surface protein GP5 exhibited increased production of PRRSV-neutralizing antibodies relative to the levels of neutralizing antibodies produced by pigs immunized with wild type (wt) or glycosylated GP5. This invention provides for methods of obtaining improved immune responses in pigs to PRRSV, compositions useful for obtaining the improved immune responses as well as isolated polynucleotides that encode hypoglycosylated variants of PRRSV major surface protein GP5.

Protection Against Mucosal Shiv Challenge By Peptide And Helper-Dependent Adenovirus Vaccines, Eric A. Weaver, Pramod N. Nehete, Bharti P. Nehete, Stephanie J. Buchl, Donna Palmer, David C. Montefiori, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Groups of rhesus macaques that had previously been immunized with HIV-1 envelope (env) peptides and first generation adenovirus serotype 5 (FG-Ad5) vaccines expressing the same peptides were immunized intramuscularly three times with helperdependent adenovirus (HD-Ad) vaccines expressing only the HIV-1 envelope from JRFL. No gag, pol, or other SHIV genes were used for vaccination. One group of the FG-Ad5- immune animals was immunized three times with HD-Ad5 expressing env. One group was immunized by serotype-switching with HD-Ad6, HD-Ad1, and HD-Ad2 expressing env. Previous work demonstrated that serum antibody levels against env were significantly higher in the serotype-switched group than in …

The Elucidation Of Metabolic Pathways And Their Improvements Using Stable Optimization Of Large-Scale Kinetic Models Of Cellular Systems, Evgeni V. Nikolaev

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Metabolic engineering of cellular systems to maximize reaction fluxes or metabolite concentrations still presents a significant challenge by encountering unpredictable instabilities that can be caused by simultaneous or consecutive enhancements of many reaction steps. It can therefore be important to select carefully small subsets of key enzymes for their subsequent stable modification compatible with cell physiology. To address this important problem, we introduce a general mixed integer non-linear problem (MINLP) formulation to compute automatically which enzyme levels should be modulated and which enzyme regulatory structures should be altered to achieve the given optimization goal using non-linear kinetic models of relevant …

Role Of Cd4+Cd25+ Regulatory T Lymphocytes In Experimental Toxoplasmosis, Sanjay Varikuti

Masters Theses & Specialist Projects

Toxoplasmosis is an important cause of congenital disease, and it is one of the most common opportunistic infections in patients with acquired immunodeficiency syndrome. The need for a reliable experimental model of this infection is crucial not only for achieving a better understanding of the patho-physiology of the disease, but also for developing better methods for evaluating new therapeutic regimens. The purpose of the present study was to investigate the role of CD4+CD25+ T regulatory lymphocytes in mice infected with Toxoplasma gondii. T regulatory (Treg) cells have been shown to play an important role in our immune system in …

The Effect Of Endothelin-1 On The Expression Of Cdk Inhibitors P21 & P27 In Bovine Corneal Endothelial Cells, Lakshmi Reddy Bollu

Masters Theses & Specialist Projects

Mammalian corneal endothelial cells are considered to be non-proliferative due to the arrest of cells at the G1 phase of the cell cycle. The purpose of this study was to determine whether the down regulation of cyclin dependant kinase inhibitors (p21cip1 and p27kip1) levels by Endothelin-1 (ET-1), would overcome the G1 phase arrest and promote cell cycle progression and proliferation in cultured BCECs (Bovine corneal endothelial cells). BCECs were isolated from bovine corneas and cultured in DMEM supplemented with 10% serum. 5-Bromo 2-deoxy Uridine (BrdU) incorporation was determined in serum starved cultures in 24-well plates as a measure of cell …

Single-Amino-Acid Alterations In A Highly Conserved Central Region Of Vesicular Stomatitis Virus N Protein Differentially Affect The Viral Nucleocapsid Template Functions, Debasis Nayak, Debasis Panda, Subash C. Das, Ming Lou, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

The nucleocapsid protein (N) of vesicular stomatitis virus and other rhabdoviruses plays a central role in the assembly and template functions of the viral N-RNA complex. The crystal structure of the viral N-RNA complex suggests that the central region of the N protein interacts with the viral RNA. Sequence alignment of rhabdovirus N proteins revealed several highly conserved regions, one of which spanned residues 282 to 291 (GLSSKSPYSS) in the central region of the molecule. Alanine-scanning mutagenesis of this region suggested that replacement of the tyrosine residue at position 289 (Y289) with alanine resulted in an N-RNA template that is …

Effects Of Estrogen On Muscle Damage In Response To An Acute Resistance Exercise Protocol, Megan R. Wolf

Honors Scholar Theses

Creatine Kinase (CK) is used as a measure of exercise-induced muscle membrane damage. During acute eccentric (muscle lengthening) exercise, muscle sarcolemma, sarcoplasmic reticulum, and Z-lines are damaged, thus causing muscle proteins and enzymes to leak into the interstitial fluid.

Strenuous eccentric exercise produces an elevation of oxygen free radicals, which further increases muscle damage. Muscle soreness and fatigue can be attributed to this membrane damage. Estradiol, however, may preserve membrane stability post-exercise (Brancaccio, Maffulli, & Limongelli, 2007; Carter, Dobridge, & Hackney, 2001; Tiidus, 2001). Because estradiol has a similar structure to Vitamin E, which is known to have antioxidant properties, …

Comparison Of Replication-Competent, First Generation, And Helper-Dependent Adenoviral Vaccines, Eric A. Weaver, Pramod N. Nehete, Stephanie S. Buchl, Julien S. Senac, Donna Palmer, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

All studies using human serotype 5 Adenovirus (Ad) vectors must address two major obstacles: safety and the presence of pre-existing neutralizing antibodies. Helper-Dependent (HD) Ads have been proposed as alternative vectors for gene therapy and vaccine development because they have an improved safety profile. To evaluate the potential of HD-Ad vaccines, we compared replication-competent (RC), first-generation (FG) and HD vectors for their ability to induce immune responses in mice. We show that RC-Ad5 and HD-Ad5 vectors generate stronger immune responses than FG-Ad5 vectors. HD-Ad5 vectors gave lower side effects than RC or FG-Ad, producing lower levels of tissue damage and …

Biarsenical Labeling Of Vesicular Stomatitis Virus Encoding Tetracysteine-Tagged M Protein Allows Dynamic Imaging Of M Protein And Virus Uncoating In Infected Cells, Subash C. Das, Debasis Panda, Debasis Nayak, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

A recombinant vesicular stomatitis virus (VSV-PeGFP-M-MmRFP) encoding enhanced green fluorescent protein fused in frame with P (PeGFP) in place of P and a fusion matrix protein (monomeric red fluorescent protein fused in frame at the carboxy terminus of M [MmRFP]) at the G-L gene junction, in addition to wild-type (wt) M protein in its normal location, was recovered, but the MmRFP was not incorporated into the virions. Subsequently, we generated recombinant viruses (VSV-PeGFP-∆M-Mtc and VSV-∆M-Mtc) encoding Mprotein with a carboxy-terminal tetracysteine tag (Mtc) in place of the M protein. These recombinant viruses incorporated Mtc at levels similar to M in …

Naloxone's Pentapeptide Binding Site On Filamin A Blocks Mu Opioid Receptor–Gs Coupling And Creb Activation Of Acute Morphine, Hoau-Yan Wang, Lindsay H. Burns

Publications and Research

Chronic morphine causes the mu opioid receptor (MOR) to switch its coupling from Gi/o to Gs, resulting in excitatory signaling via both Gαs and its Gβγ dimer. Ultra-low-dose naloxone (NLX) prevents this switch and attenuates opioid tolerance and dependence. This protective effect is mediated via a high-affinity interaction of NLX to a pentapeptide region in c-terminal filamin A (FLNA), a scaffolding protein interacting with MOR. In organotypic striatal slice cultures, we now show that acute morphine induces a dose-dependent Go-to-Gs coupling switch at 5 and 15 min that resolves by 1 hr. The acute Gs coupling induced by 100 µM …

Loss Of Ski Expression In Testicular Cancer Leads To An Enhanced Invasive Phenotype Through Both Bmp-Dependent And Bmp-Independent Pathways, Amy N. Nash

Theses, Dissertations and Capstones

The proto-oncogene SKI is a transcription factor and a co-repressor of the TGFβ superfamily, including TGF

β and BMP. However, additional data suggests that SKI may function as a tumor suppressor in some cell types. The TGFβ superfamily has been implicated in cancer progression and germ cell migration. Testicular cancer afflicts men during their peak reproductive years and is the most common cancer among men of this age group. Cisplatin-based chemotherapy is the standard treatment for testicular cancer. This treatment can lead to undesirable side effects, including infertility. We have shown that SKI expression is decreased in testicular germ cell …

Human Ubc9 Contributes To Production Of Fully Infectious Human Immunodeficiency Virus Type 1 Virions, Tareq Jaber, Christopher R. Bohl, Gentry L. Lewis, Charles Wood, John T. West Jr., Robert A. Weldon Jr.

Nebraska Center for Virology: Faculty Publications

Ubc9 was identified as a cellular protein that interacts with the Gag protein of Mason-Pfizer monkey virus. We show here that Ubc9 also interacts with the human immunodeficiency virus type 1 (HIV-1) Gag protein and that their interaction is important for virus replication. Gag was found to colocalize with Ubc9 predominantly at perinuclear puncta. While cells in which Ubc9 expression was suppressed with RNA interference produced normal numbers of virions, these particles were 8- to 10-fold less infectious than those produced in the presence of Ubc9. The nature of this defect was assayed for dependence on Ubc9 during viral assembly, …

Light-Induced Fos Expression In Intrinsically Photosensitive Retinal Ganglion Cells In Melanopsin Knockout (Opn4-/-) Mice, Gary E. Pickard, Scott B. Baver, Malcolm D. Ogilvie, Patricia J. Sollars

School of Veterinary and Biomedical Sciences: Faculty Publications

Retinal ganglion cells that express the photopigment melanopsin are intrinsically photosensitive (ipRGCs) and exhibit robust synaptically driven ON-responses to light, yet they will continue to depolarize in response to light when all synaptic input from rod and cone photoreceptors is removed. The light-evoked increase in firing of classical ganglion cells is determined by synaptic input from ON-bipolar cells in the proximal sublamina of the inner plexiform layer. OFF-bipolar cells synapse with ganglion cell dendrites in the distal sublamina of the inner plexiform layer. Of the several types of ipRGC that have been described, M1 ipRGCs send dendrites exclusively into the …