Life Sciences Commons^™

Cytological And Agronomic Evaluation Of Interspecific Hybrids Between Trifolium Repens L And T. Occidentale Coombe, Syed Wajid Hussain, J. L. Ford

IGC Proceedings (1997-2023)

Trifolium occidentale is a diploid wild relative of T. repens with adaptation to dry, saline coastal habitats. Transfer of drought and salt-tolerant adaptive traits from this potential source of germplasm to T. repens could be valuable if interspecific hybridization can be achieved efficiently. To achieve hybridisation, 4x plants of T. occidentale were generated through colchicine chromosome doubling. Interspecific 4x F₁ plants were achieved without embryo rescue. F₂ populations and backcross (BC) hybrids to white clover were also efficiently achieved. Although male and female fertility in primary F₁ and F₂ hybrids were lower than in white clover, …

Studies On Morphology, Cytogenetics And Fertility Of Bc1f1 Of Hybrid F1 Between Elymus Dahuricus And Hordeum Brevisubulatum, Zaozhe Li, Jinfeng Yun, Zhuo Yu

IGC Proceedings (1997-2023)

No abstract provided.

Adaptation Mechanism And Tolerance Of Rhodopseudomonas Palustris Psb-S Under Pyrazosulfuron-Ethyl Stress, Xiang-Wen Luo, De-Yang Zhang, Teng-Hui Zhu, Xuguo Zhou, Jing Peng, Song-Bai Zhang, Yong Liu

Entomology Faculty Publications

Background: Pyrazosulfuron-ethyl is a long lasting herbicide in the agro-ecosystem and its residue is toxic to crops and other non-target organisms. A better understanding of molecular basis in pyrazosulfuron-ethyl tolerant organisms will shed light on the adaptive mechanisms to this herbicide.

Results: Pyrazosulfuron-ethyl inhibited biomass production in Rhodopseudomonas palustris PSB-S, altered cell morphology, suppressed flagella formation, and reduced pigment biosynthesis through significant suppression of carotenoids biosynthesis. A total of 1127 protein spots were detected in the two-dimensional gel electrophoresis. Among them, 72 spots representing 56 different proteins were found to be differently expressed using MALDI-TOF/TOF-MS, including 26 up- and 30 …

New Cytological, Morphological, And Chorological Data On Prospero Seisumsianum(Ruk?Ans & Zetterl.) Yıldırım (Asparagaceae) From The Zagros Area, Sami Youssef, Ahmed Mahmood, Manuel Cartereau, Errol Vela

Turkish Journal of Botany

Prospero seisumsianum (Ruk?ans & Zetterl.) Yıldırım, a species recently described in southeastern Turkey, was recorded for the first time in the flora of Iraq based on samples collected from the Amadya and Duhok areas (northern Iraq). Our contribution here will be to find out more about its description, cytology, and chorology. The specimen collected from the Mesopotamian dry plain differs slightly from those collected from the mountainous Zagros forest area, but converges after a cultivation period. Both are treated here as P. seisumsianum and have the same genome size (2C = 8.77 ± 0.24 pg) corresponding to a diploid level. …

Assessment Of Tumor-Induced Pain And C-Reactive Protein Levels In Dogs With Caninetransmissible Venereal Tumors, Waqas Ahmad, Muti-Ur- Rehman, Aftab Ahmad Anjum, Gulbeena Saleem, Ubaid Ur Rehman Zia, Muhammad Azeem, Fahad Akram

Turkish Journal of Veterinary & Animal Sciences

The aim of this study was to determine the impact of tumor volume on generalized behavior, pain perception, and serum C-reactive protein (CRP) in dogs with canine transmissible venereal tumors (CTVTs). Pain scoring was performed using the Glasgow Composite Measure Pain Scale Short-Form. Cytomorphology of the tumors was studied through fine-needle aspiration and histopathology. Molecular identification of CTVTs was carried out using PCR assays based on LINE-1/c-myc. Hematological profiles including complete blood count and CRP were analyzed using an automatic hematology analyzer and immunoturbidimetric assays, respectively. Chi-square and regression analysis statistics were used for data analysis. Results of the study …

Endometrial Cytology As A Diagnostic Tool For Subclinical Endometritis In Beef Heifers, Carlos Moscuzza, Guadalupe Alvarez, Betiana Gutierrez, Marcelo Zurita, Marcelo Tropeano, Roberto Perna

Turkish Journal of Veterinary & Animal Sciences

The obstetric assistance of dystocia in field conditions promotes greater bacterial contamination of the uterus, causing subclinical endometritis. The aim of this study was to determine the occurrence of subclinical endometritis in beef heifers receiving professional calving assistance, and to evaluate endometrial cytology as a diagnostic technique compared to uterine biopsy. A group of 829 Angus heifers were assisted at calving. Dystocia was classified based on difficulty at assistance, which was estimated as complex or simple. At the end of the calving season, 93 dystocic heifers were reported (10.7%). The percentage of simple resolution and complex resolution was 88.2% and …

Functional And Developmental Identification Of A Molecular Subtype Of Brain Serotonergic Neuron Specialized To Regulate Breathing Dynamics, Rachael D. Brust, Andrea E. Corcoran, George B. Richerson, Eugene Nattie, Susan M. Dymecki

Dartmouth Scholarship

Serotonergic neurons modulate behavioral and physiological responses from aggression and anxiety to breathing and thermoregulation. Disorders involving serotonin (5HT) dysregulation are commensurately heterogeneous and numerous. We hypothesized that this breadth in functionality derives in part from a developmentally determined substructure of distinct subtypes of 5HT neurons each specialized to modulate specific behaviors. By manipulating developmentally defined subgroups one by one chemogenetically, we find that the Egr2-Pet1 subgroup is specialized to drive increased ventilation in response to carbon dioxide elevation and acidosis. Furthermore, this subtype exhibits intrinsic chemosensitivity and modality-specific projections-increasing firing during hypercapnic acidosis and selectively projecting to respiratory chemosensory …

Combinatorial Activation Of Stat3 By Egf And Thrombin In Endothelial Cells, Matthew S. Waitkus

ETD Archive

Endothelial cells line the luminal surface of blood vessels and form a regulatory interface between the bloodstream and underlying tissues. The endothelium responds to diverse, and potentially conflicting, environmental signals to regulate vessel growth, leukocyte adhesion, thrombogenicity, and vascular tone. Signaling pathways may interact, or "crosstalk," in combinatorial signaling environments to enable cells to process disparate extracellular information at downstream signaling nodes and formulate appropriate biological responses based on combinations of extracellular stimuli. We have reported that simultaneous stimulation of endothelial cells with EGF and thrombin synergistically induces expression of immediate early genes (IEGs) associated with growth and angiogenesis. We …

Conformational Regulation Of Membrane Localization And Activation Of Talin, Pallavi Dwivedi

ETD Archive

Talin is a cytosolic protein which is known to be one of the key players involved in integrin mediated cell adhesion dependent processes, including blood coagulation, and tissue remodeling. It connects the extracellular matrix with the actin cytoskeleton. Talin comprises of a head domain (talin-H) and a rod domain (talin-R). Talin-H is further subdivided in F0, F1, F2 and F3 domains. Talin-R contains 13 contiguous helical bundle domains (R1-R13) followed by an actin binding dimerization domain (DD). The F3 domain contains a key integrin binding site that regulates integrin activation. In our previous studies, we have shown that cytosolic talin …

An Expanded View Of The Eukaryotic Cytoskeleton, James B. Moseley

Dartmouth Scholarship

A rich and ongoing history of cell biology research has defined the major polymer systems of the eukaryotic cytoskeleton. Recent studies have identified additional proteins that form filamentous structures in cells and can self-assemble into linear polymers when purified. This suggests that the eukaryotic cytoskeleton is an even more complex system than previously considered. In this essay, I examine the case for an expanded definition of the eukaryotic cytoskeleton and present a series of challenges for future work in this area.

Bioengineered Lysozyme Reduces Bacterial Burden And Inflammation In A Murine Model Of Mucoid Pseudomonas Aeruginosa Lung Infection, Charlotte C. Teneback, Thomas C. Scanlon, Matthew J. Wargo, Jenna L. Bement, Karl E. Griswold, Laurie W. Leclair

Dartmouth Scholarship

The spread of drug-resistant bacterial pathogens is a growing global concern and has prompted an effort to explore potential adjuvant and alternative therapies derived from nature's repertoire of bactericidal proteins and peptides. In humans, the airway surface liquid layer is a rich source of antibiotics, and lysozyme represents one of the most abundant and effective antimicrobial components of airway secretions. Human lysozyme is active against both Gram-positive and Gram-negative bacteria, ac

P53'S Choice Of Myocardial Death Or Survival: Oxygen Protects Infarct Myocardium By Recruiting P53 On Nos3 Promoter Through Regulation Of P53-Lys118 Acetylation, Rajan Gogna, Esha Madan, Mahmood Khan, Uttam Pati, Periannan Kuppusamy

Dartmouth Scholarship

Myocardial infarction, an irreversible cardiac tissue damage, involves progressive loss of cardiomyocytes due to p53-mediated apoptosis. Oxygenation is known to promote cardiac survival through activation of NOS3 gene. We hypothesized a dual role for p53, which, depending on oxygenation, can elicit apoptotic death signals or NOS3-mediated survival signals in the infarct heart. p53 exhibited a differential DNA-binding, namely, BAX-p53RE in the infarct heart or NOS3-p53RE in the oxygenated heart, which was regulated by oxygen-induced, post- translational modification of p53. In the infarct heart, p53 was heavily acetylated at Lys118 residue, which was exclusively reversed in the oxygenated heart, apparently regulated …

Differential Regulation Of White-Opaque Switching By Individual Subunits Of Candida Albicans Mediator, Anda Zhang, Zhongle Liu, Lawrence C. Myers

Dartmouth Scholarship

The multisubunit eukaryotic Mediator complex integrates diverse positive and negative gene regulatory signals and transmits them to the core transcription machinery. Mutations in individual subunits within the complex can lead to decreased or increased transcription of certain subsets of genes, which are highly specific to the mutated subunit. Recent studies suggest a role for Mediator in epigenetic silencing. Using white-opaque morphological switching in Candida albicans as a model, we have shown that Mediator is required for the stability of both the epigenetic silenced (white) and active (opaque) states of the bistable transcription circuit driven by the master regulator Wor1. Individual …

A Novel Method For Comparative Analysis Of Retinal Specialization Traits From Topographic Maps, Bret A. Moore, Jason M. Kamilar, Shaun P. Collin, Olaf R. P. Bininda-Emonds, Nathaniel J. Dominy, Margaret I. Hall, Christopher P. Hessy, Sonke Johnsen, Thomas J. Lisney, Ellis R. Loew, Gillian Moritz

Dartmouth Scholarship

Abstract Vertebrates possess different types of retinal specializations that vary in number, size, shape, and position in the retina. This diversity in retinal configuration has been revealed through topographic maps, which show variations in neuron density across the retina. Although topographic maps of about 300 vertebrates are available, there is no method for characterizing retinal traits quantitatively. Our goal is to present a novel method to standardize information on the position of the retinal specializations and changes in retinal ganglion cell (RGC) density across the retina from published topographic maps. We measured the position of the retinal specialization using two …

Usefulness Of Ca 15-3 For Breast Or Ovarian Primary Sites In Metastatic Adenocarcinoma Of Pleural Fluid, Serpi̇l Oğuztüzün, Murat Kiliç, Ni̇sa Tandogan, Lati̇f Öztürk

Turkish Journal of Biology

This study was conducted to evaluate the diagnostic value of CA 15-3, mammaglobin, c-erbB-2, estrogen receptor (ER), progesterone receptor (PR), CK 20, and CA 125 for detecting metastatic breast and ovarian carcinoma in pleural fluids. The material under study consisted of 26 pleural effusions from invasive breast and ovarian cancer patients from the Hannover Cytopathology Institute. Expressions of these markers were studied using immunocytochemistry. All of the breast cancer cases studied showed a positive reaction with CA 15-3, while only 36% with mammaglobin, 21% with c-erbB-2, 36% with ER, and 7% with PR were positive. The sensitivities of CK 20, …

Elucidating The Role Of Bone Morphogenetic Proteins And B-Lymphocyte Maturation Protein 1 During Primordial Germ Cell Specification, Laughing Bear Torrez Dulgeroff

Theses Digitization Project

This study will present an optimized protocol to induce and isolate primordial germ cells (PGC) from hESC and hiPSC. Human embrionic stem cells (hESC and induced pluripotent stem cells (iPSC) provide a model for studying paradigms of early development.

Axl2 Integrates Polarity Establishment, Maintenance, And Environmental Stress Response In The Filamentous Fungus Ashbya Gossypii, Jonathan F. Anker, Amy S. Gladfelter

Dartmouth Scholarship

In budding yeast, new sites of polarity are chosen with each cell cycle and polarization is transient. In filamentous fungi, sites of polarity persist for extended periods of growth and new polarity sites can be established while existing sites are maintained. How the polarity establishment machinery functions in these distinct growth forms found in fungi is still not well understood. We have examined the function of Axl2, a transmembrane bud site selection protein discovered in Saccharomyces cerevisiae, in the filamentous fungus Ashbya gossypii. A. gossypii does not divide by budding and instead exhibits persistent highly polarized growth, and multiple axes …

Single Cell Analysis For The Characterization Of Cell Populations Using A Live Cell Array, Maureen Ann Walling

Legacy Theses & Dissertations (2009 - 2024)

In the past decade, the shift from whole cell population analyses towards single cell measurement methods and techniques is based on experimental results that reveal significant levels of non-genetic heterogeneity in clonal cell populations. This heterogeneity manifests in multiple aspects of cell activity and is, in part, a result of stochastic noise in processes leading to gene expression, namely transcription and translation. The growing understanding of this occurrence has led to the development of methods to monitor and analyze heterogeneity for a more thorough description of cell populations and overall activity.

Reversible Deficiencies In Flagellar Beating And Axonemal Assembly, Mei Wei

Dissertations (1934 -)

Axonemal complexes in flagella are largely prepackaged in the cell body. As such, one mutation often results in the absence of the co-assembled components and permanent motility deficiencies. For example, a Chlamydomonas mutant defective in RSP4 in the radial spoke, which is critical for bend propagation, has paralyzed flagella that also lack the paralogue RSP6 and three additional radial spoke proteins. Intriguingly, recent studies showed that several mutant strains contain a mixed population of swimmers and paralyzed cells despite their identical genetic background. Here we report a cause underlying these variations. Two new mutants lacking RSP6 swim processively and other …

Hops Initiates Vacuole Docking By Tethering Membranes Before Trans-Snare Complex Assembly, Christopher M. Hickey, William Wickner

Dartmouth Scholarship

Vacuole homotypic fusion has been reconstituted with all purified components: vacuolar lipids, four soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins, Sec17p, Sec18p, the Rab Ypt7p, and the hexameric homotypic fusion and vacuole protein sorting complex (HOPS). HOPS is a Rab-effector with direct affinity for SNAREs (presumably via its Sec1-Munc18 homologous subunit Vps33p) and for certain vacuolar lipids. Each of these pure vacuolar proteins was required for optimal proteoliposome clustering, raising the question of which was most directly involved. We now present model subreactions of clustering and fusion that reveal that HOPS is the direct agent of tethering. The …

Genetic And Molecular Characterization Of A Cryptochrome From The Filamentous Fungus Neurospora Crassa, Allan C. Froehlich, Chen-Hui Chen, William J. Belden, Cornelia Madeti

Dartmouth Scholarship

In plants and animals, cryptochromes function as either photoreceptors or circadian clock components. We have examined the cryptochrome from the filamentous fungus Neurospora crassa and demonstrate that Neurospora cry encodes a DASH-type cryptochrome that appears capable of binding flavin adenine dinucleotide (FAD) and methenyltetrahydrofolate (MTHF). The cry transcript and CRY protein levels are strongly induced by blue light in a wc-1-dependent manner, and cry transcript is circadianly regulated, with a peak abundance opposite in phase to frq. Neither deletion nor overexpression of cry appears to perturb the free-running circadian clock. However, cry disruption knockout mutants show a small phase delay …

Farnesol Induces Hydrogen Peroxide Resistance In Candida Albicans Yeast By Inhibiting The Ras-Cyclic Amp Signaling Pathway, Aurélie Deveau, Amy E. Piispanen, Angelyca A. Jackson, Deborah A. Hogan

Dartmouth Scholarship

Farnesol, a Candida albicans cell-cell signaling molecule that participates in the control of morphology, has an additional role in protection of the fungus against oxidative stress. In this report, we show that although farnesol induces the accumulation of intracellular reactive oxygen species (ROS), ROS generation is not necessary for the induction of catalase (Cat1)-mediated oxidative-stress resistance. Two antioxidants, α-tocopherol and, to a lesser extent, ascorbic acid effectively reduced intracellular ROS generation by farnesol but did not alter farnesol-induced oxidative-stress resistance. Farnesol inhibits the Ras1-adenylate cyclase (Cyr1) signaling pathway to achieve its effects on morphology under hypha-inducing conditions, and we demonstrate …

Dopamine D1 Receptor-Mediated Nmda Receptor Insertion Depends On Fyn But Not Src Kinase Pathway In Prefrontal Cortical Neurons, Jian-Li Hu, Gang Liu, Yan-Chun Li, Wen-Jun Gao, Yueqiao Huang

PCOM Scholarly Papers

Background. Interactions between dopamine and glutamate in the prefrontal cortex are essential for cognitive functions such as working memory. Modulation of N-methyl-D-aspartic acid (NMDA) receptor functions by dopamine D1 receptor is believed to play a critical role in these functions. The aim of the work reported here is to explore the signaling pathway underlying D1 receptor-mediated trafficking of NMDA receptors in cultured rat prefrontal cortical neurons. Results. Activation of D1 receptor by selective agonist SKF-81297 significantly increased the expression of NR2B subunits. This effect was completely blocked by small interfering RNA knockdown of Fyn, but not Src. Under control conditions, …

Mtorc1 Hyperactivity Inhibits Serum Deprivation-Induced Apoptosis Via Increased Hexokinase Ii And Glut1 Expression, Sustained Mcl-1 Expression, And Glycogen Synthase Kinase 3Β Inhibition, Prashanth T. Bhaskar, Veronique Nogueira, Krushna C. Patra, Sang-Min Jeon, Youngkyu Park, R. Brooks Robey, Nissim Hay

Dartmouth Scholarship

The current concept is that Tsc-deficient cells are sensitized to apoptosis due to the inhibition of Akt activity by the negative feedback mechanism induced by the hyperactive mTORC1. Unexpectedly, however, we found that Tsc1/2-deficient cells exhibit increased resistance to serum deprivation-induced apoptosis. mTORC1 hyperactivity contributes to the apoptotic resistance of serum-deprived Tsc1/2-deficient cells in part by increasing the growth factor-independent expression of hexokinase II (HKII) and GLUT1. mTORC1-mediated increase in hypoxia-inducible factor 1α (HIF1α) abundance, which occurs in the absence of serum in normoxic Tsc2-deficient cells, contributes to these changes. Increased HIF1α abundance in these cells is attributed to both …

Disruption Of Osysl15 Leads To Iron Inefficiency In Rice Plants, Sichul Lee, Jeff C. Chiecko, Sun A. Kim, Elsbeth L. Walker, Youngsook Lee, Mary Lou Guerinot, Gyhheung An

Dartmouth Scholarship

Uptake and translocation of metal nutrients are essential processes for plant growth. Graminaceous species release phytosiderophores that bind to Fe³⁺; these complexes are then transported across the plasma membrane. We have characterized OsYSL15, one of the rice (Oryza sativa) YS1-like (YSL) genes that are strongly induced by iron (Fe) deficiency. The OsYSL15 promoter fusion to β-glucuronidase showed that it was expressed in all root tissues when Fe was limited. In low-Fe leaves, the promoter became active in all tissues except epidermal cells. This activity was also detected in flowers and seeds. The OsYSL15:green …

N-Acetylcysteine Amide Decreases Oxidative Stress But Not Cell Death Induced By Doxorubicin In H9c2 Cardiomyocytes, Rong Shi, Chuan-Chin Huang, Robert Aronstam, Nuran Ercal, Adam Martin, Yue-Wern Huang

Biological Sciences Faculty Research & Creative Works

Background: While doxorubicin (DOX) is widely used in cancer chemotherapy, long-term severe cardiotoxicity limits its use. This is the first report of the chemoprotective efficacy of a relatively new thiol antioxidant, N-acetylcysteine amide (NACA), on DOX-induced cell death in cardiomyocytes. We hypothesized that NACA would protect H9c2 cardiomyocytes from DOX-induced toxicity by reducing oxidative stress. Accordingly, we determined the ability of NACA to mitigate the cytotoxicity of DOX in H9c2 cells and correlated these effects with the production of indicators of oxidative stress.

Results: DOX at 5 μM induced cardiotoxicity while 1) increasing the generation of reactive oxygen species (ROS), …

Regulation Of Distinct Septin Rings In A Single Cell By Elm1p And Gin4p Kinases, Bradley S. Demay, Rebecca A. Meseroll, Patricia Occhipinti, Amy S. Gladfelter

Dartmouth Scholarship

Septins are conserved, GTP-binding proteins that assemble into higher order structures, including filaments and rings with varied cellular functions. Using four-dimensional quantitative fluorescence microscopy of Ashbya gossypii fungal cells, we show that septins can assemble into morphologically distinct classes of rings that vary in dimensions, intensities, and positions within a single cell. Notably, these different classes coexist and persist for extended times, similar in appearance and behavior to septins in mammalian neurons and cultured cells. We demonstrate that new septin proteins can add through time to assembled rings, indicating that septins may continue to polymerize during ring maturation. Different classes …

Furfural Inhibits Growth By Limiting Sulfur Assimilation In Ethanologenic Escherichia Coli Strain Ly180, Elliot N. Miller, Laura R. Jarboe, Peter C. Turner, Prita Pharkya, Lorraine P. Yomano, Sean W. York, David Nunn, K. T. Shanmugan, Lonnie O. Ingram

Laura R. Jarboe

A wide variety of commercial products can be potentially made from monomeric sugars produced by the dilute acid hydrolysis of lignocellulosic biomass. However, this process is accompanied by side products such as furfural that hinder microbial growth and fermentation. To investigate the mechanism of furfural inhibition, mRNA microarrays of an ethanologenic strain of Escherichia coli (LY180) were compared immediately prior to and 15 min after a moderate furfural challenge. Expression of genes and regulators associated with the biosynthesis of cysteine and methionine was increased by furfural, consistent with a limitation of these critical metabolites. This was in contrast to a …

Ovarian Development In Mice Requires The Gata4-Fog2 Transcription Complex, Nikolay L. Manuylov, Fatima O. Smagulova, Lyndsay Leach, Sergei G. Tevosian

Dartmouth Scholarship

We have demonstrated previously that mammalian sexual differentiation requires both the GATA4 and FOG2 transcriptional regulators to assemble the functioning testis. Here we have determined that the sexual development of female mice is profoundly affected by the loss of GATA4-FOG2 interaction. We have also identified the Dkk1 gene, which encodes a secreted inhibitor of canonical beta-catenin signaling, as a target of GATA4-FOG2 repression in the developing ovary. The tissue-specific ablation of the beta-catenin gene in the gonads disrupts female development. In Gata4(ki/ki); Dkk1(-/-) or Fog2(-/-); Dkk1(-/-) embryos, the normal ovarian gene expression pattern is partially restored. Control of ovarian development …

An Insight Into Gait Complex Mediated Translational Silencing, Purvi Kapasi

ETD Archive

Transcript-specific translational control restricts macrophage inflammatory gene expression. The pero-inflammatory cytokine IFN-Îđ induces the phosphorylation of human ribosomal protein L13a and its subsequent release from 60S ribosome. L13a is a component of the interferon-gamma-activated inhibitor of translation (GAIT). The GAIT complex binds a defined element in the 3'-untranslated region (UTR) of ceruloplasmin (Cp) mRNA and causes delayed silencing of translation. In this research, we elucidate the molecular mechanism underlying L13a translational silencing activity. L13a mediates translational silencing particularly, when driven by internal ribosome entry sites (IRESs) that requires the initiation factor eIF4G, but is resistant to silencing when driven by …