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Full-Text Articles in Life Sciences

Molecular Studies On The Interactions Between Biomphalaria Snails And Schistosoma Mansoni, Lijun Lu Dec 2020

Molecular Studies On The Interactions Between Biomphalaria Snails And Schistosoma Mansoni, Lijun Lu

Biology ETDs

Biomphalaria snails serve as vectors for Schistosoma mansoni, a trematode causing human schistosomiasis. Control of Schistosoma mansoni involves chemotherapy of affected people, but new control methods built on improved understanding of schistosome-snail interactions are needed. My dissertation applies molecular and bioinformatics approaches to understand such interactions. Chapter 1 shows that significant differences exist among Biomphalaria species in Africa with respect to their ability to support schistosome development. Chapters 2 and 3 reveal the transcriptional responses of Biomphalaria glabrata susceptible (SUS) or resistant (RES) to Schistosoma mansoni. Chapter 2 identifies a new family of snail immune factors, the AIG …


Functional Investigations Of Proteins And Enzymatic Toxins From Full-Length-Enriched Cdna Of Timber Rattlesnake (Crotalus Horridus), Joshua Osula Dec 2020

Functional Investigations Of Proteins And Enzymatic Toxins From Full-Length-Enriched Cdna Of Timber Rattlesnake (Crotalus Horridus), Joshua Osula

Theses

Snake Venom is a highly modified form of saliva, contains hundreds of zootoxins, necrotoxins, cytotoxins, neurotoxins, and mytotoxins, all of which are primarily made up of mostly proteins, polypeptides, and other components such as enzymes, lipids, and carbohydrates. Although snake venom is known for its harmful effects, it has also had a positive impact in scientific discovery and medicine. Some toxins from snakes function to inhibit pain, and this means they can be very effective analgesics. For instance, crotalphine is considered a 14-amino-acid-peptide that has a disulfide bond and shows analgesic properties through TRPA1 desensitization. This …


A Gene Expression Profile Associated With Successful Cns Axon Regeneration In Xenopus Laevis, Jamie L. Belrose Dec 2020

A Gene Expression Profile Associated With Successful Cns Axon Regeneration In Xenopus Laevis, Jamie L. Belrose

Legacy Theses & Dissertations (2009 - 2024)

Background: The South African claw-toed frog, Xenopus laevis, is uniquely suited for studying differences between regenerative and non-regenerative responses to CNS injury within the same organism, because some CNS neurons (e.g., retinal ganglion cells after optic nerve crush (ONC)) regenerate axons throughout life, whereas others (e.g., hindbrain neurons after spinal cord injury (SCI)) lose this capacity as tadpoles metamorphose into frogs. Tissues from these CNS regions (frog ONC eye, tadpole SCI hindbrain, frog SCI hindbrain) were used in a three-way RNA-seq study of axotomized CNS axons to identify potential core gene expression programs for successful CNS axon regeneration.


Novel Small Rnas Expressed By Bartonella Bacilliformis Under Multiple Conditions Reveal Potential Mechanisms For Persistence In The Sand Fly Vector And Human Host, Shaun Wachter, Linda D. Hicks, Rahul Raghavan, Michael F. Minnick Nov 2020

Novel Small Rnas Expressed By Bartonella Bacilliformis Under Multiple Conditions Reveal Potential Mechanisms For Persistence In The Sand Fly Vector And Human Host, Shaun Wachter, Linda D. Hicks, Rahul Raghavan, Michael F. Minnick

Biology Faculty Publications and Presentations

Bartonella bacilliformis, the etiological agent of Carrión’s disease, is a Gram-negative, facultative intracellular alphaproteobacterium. Carrión’s disease is an emerging but neglected tropical illness endemic to Peru, Colombia, and Ecuador. B. bacilliformis is spread between humans through the bite of female phlebotomine sand flies. As a result, the pathogen encounters significant and repeated environmental shifts during its life cycle, including changes in pH and temperature. In most bacteria, small non-coding RNAs (sRNAs) serve as effectors that may post-transcriptionally regulate the stress response to such changes. However, sRNAs have not been characterized in B. bacilliformis, to date. We …


Direct Binding Of Tfeα Opens Dna Binding Cleft Of Rna Polymeras, Sung-Hoon Jun, Jaekyung Hyun, Hoyoung Kim, Michael S. Bartlett, Hyun-Soo Cho, Katsuhiko S. Murakami Nov 2020

Direct Binding Of Tfeα Opens Dna Binding Cleft Of Rna Polymeras, Sung-Hoon Jun, Jaekyung Hyun, Hoyoung Kim, Michael S. Bartlett, Hyun-Soo Cho, Katsuhiko S. Murakami

Biology Faculty Publications and Presentations

Opening of the DNA binding cleft of cellular RNA polymerase (RNAP) is necessary for transcription initiation but the underlying molecular mechanism is not known. Here, we report on the cryo-electron microscopy structures of the RNAP, RNAP-TFEα binary, and RNAPTFEα-promoter DNA ternary complexes from archaea, Thermococcus kodakarensis (Tko). The structures reveal that TFEα bridges the RNAP clamp and stalk domains to open the DNA binding cleft. Positioning of promoter DNA into the cleft closes it while maintaining the TFEα interactions with the RNAP mobile modules. The structures and photo-crosslinking results also suggest that the conserved aromatic residue in the extended winged-helix …


Changes In Gene Expression Profiles In Müller Glia Following Exposure To An Α7 Nicotinic Acetylcholine Receptor Agonist, Megan L. Stanchfield Jul 2020

Changes In Gene Expression Profiles In Müller Glia Following Exposure To An Α7 Nicotinic Acetylcholine Receptor Agonist, Megan L. Stanchfield

Masters Theses

Previous studies from this lab have determined that dedifferentiation of Müller glia (MG) occurs after application of an α7 nicotinic acetylcholine receptor agonist, PNU-282987 (PNU), to retinal pigment epithelial (RPE) cells in adult rodents. This study was designed to explore the role of the HB-EGF/Ascl1/Lin28a signaling pathway in MG dedifferentiation to retinal progenitor cells. RNAseq was performed on MG following contact with RPE-J cells treated with PNU-282987. Up- or down-regulated genes were compared with published literature of MG dedifferentiation that occurs in lower vertebrate regeneration or with transcript profiles during early mammalian development. Between 8-12 hours, up-regulation was observed in …


Combining Experimental Evolution And Genomics To Understand How Seed Beetles Adapt To A Marginal Host Plant, Alexandre Rêgo, Samridhi Chaturvedi, Amy Springer, Alexandra M. Lish, Caroline L. Barton, Karen M. Kapheim, Frank J. Messina, Zachariah Gompert Apr 2020

Combining Experimental Evolution And Genomics To Understand How Seed Beetles Adapt To A Marginal Host Plant, Alexandre Rêgo, Samridhi Chaturvedi, Amy Springer, Alexandra M. Lish, Caroline L. Barton, Karen M. Kapheim, Frank J. Messina, Zachariah Gompert

Biology Faculty Publications

Genes that affect adaptive traits have been identified, but our knowledge of the genetic basis of adaptation in a more general sense (across multiple traits) remains limited. We combined population-genomic analyses of evolve-and-resequence experiments, genome-wide association mapping of performance traits, and analyses of gene expression to fill this knowledge gap and shed light on the genomics of adaptation to a marginal host (lentil) by the seed beetle Callosobruchus maculatus. Using population-genomic approaches, we detected modest parallelism in allele frequency change across replicate lines during adaptation to lentil. Mapping populations derived from each lentil-adapted line revealed a polygenic basis for …


Pthr1/Sox9 And Idh1/Idh2 Relative Expression In Primary Chondrocyte And Chondrosarcoma Cells Under The Synergistic Influence Of Inducible Hypoxia And Extracellular Acidosis, Kostika Vangjeli Apr 2020

Pthr1/Sox9 And Idh1/Idh2 Relative Expression In Primary Chondrocyte And Chondrosarcoma Cells Under The Synergistic Influence Of Inducible Hypoxia And Extracellular Acidosis, Kostika Vangjeli

Biological Sciences Theses & Dissertations

Cartilage cells (Chondrocytes) grow in rather unique environmental conditions in the human body. Cartilage is avascular tissue and lacks innervation. Its main source of nutrients is derived from the synovial fluid and/or perichondrium. Consequently, these cells must survive and thrive under hypoxic and acidic stressors. Published data suggests that there are a multitude of genes affected from either one of these two stressors or both. However, these factors are frequently overlooked in cartilage research, and results are reported in either normoxia/pH=7.0 conditions, or they only account for one of the conditions. The scope of this study is to examine how …


De-Coding The Impact Of Evolved Changes In Gene Expression And Cellular Phenotype On Primate Evolution, Trisha Zintel Feb 2020

De-Coding The Impact Of Evolved Changes In Gene Expression And Cellular Phenotype On Primate Evolution, Trisha Zintel

Doctoral Dissertations

The goal of the dissertation work outlined here was to investigate the influence of proximal processes contributing to evolutionary differences in phenotypes among primate species. There are numerous previous comparative analyses of gene expression between primate brain regions. However, primate brain tissue samples are relatively rare, and my results have contributed to the pre-existing data on more well-studied primates (i.e. humans, chimpanzees, macaques, marmosets) as well as produced information on more rarely-studied primates (i.e. patas monkey, siamang, spider monkey). Additionally, the primary visual cortex has not previously been as extensively studied at the level of gene expression as other brain …


Top-Down And Bottom-Up Controls On Microeukaryotic Diversity (I.E., Amplicon Analyses Of Sar Lineages) And Function (I.E., Metatranscriptome Analyses) Assessed In Microcosm Experiments, Jean David Grattepanche, Laura A. Katz Jan 2020

Top-Down And Bottom-Up Controls On Microeukaryotic Diversity (I.E., Amplicon Analyses Of Sar Lineages) And Function (I.E., Metatranscriptome Analyses) Assessed In Microcosm Experiments, Jean David Grattepanche, Laura A. Katz

Biological Sciences: Faculty Publications

The availability of high-throughput sequencing (HTS) has transformed our understanding of the diversity of microbial eukaryotes (i.e., protists) across diverse habitats. Yet relating this biodiversity to function remains a challenge, particularly in the context of microbial food webs. Here we perform a set of microcosm experiments to evaluate the impact of changing predator and prey concentrations on a marine protist community, focusing on SAR (Stramenopila, Alveolata, and Rhizaria) lineages. We combine an estimate of taxonomic diversity through analysis of SSU-rDNA amplicons with metatranscriptomics, a proxy for function. We assess changes in a community sampled from New England waters with varying …


Poly (I:C)- And Doxorubicin-Loaded Magnetic Dendrimeric Nanoparticles Affect The Apoptosis-Related Gene Expressions In Mcf-7 Cells, Rouhollah Khodadust, Aktan Alpsoy, Gözde Ünsoy, Ufuk Gündüz Jan 2020

Poly (I:C)- And Doxorubicin-Loaded Magnetic Dendrimeric Nanoparticles Affect The Apoptosis-Related Gene Expressions In Mcf-7 Cells, Rouhollah Khodadust, Aktan Alpsoy, Gözde Ünsoy, Ufuk Gündüz

Turkish Journal of Biology

Use of nanoparticles as drug carrier vectors has great potential to circumvent the limitations associated with chemotherapy, including drug resistance and destructive side effects. For this purpose, magnetic generation 4 dendrimeric nanoparticles were prepared to carry chemotherapeutic agent doxorubicin (G:4-DOX) and immune modulator polyinosinic:polycytidylic acid [Poly(I:C)]. As previously reported, DOX and Poly(I:C) was loaded onto G4 nanoparticles (PIC-G4-DOX). Cellular internalization study using confocal microscopy demonstrated high levels of cellular internalization of PIC-G4-DOX nanoparticles by MCF-7 cells. This resulted in higher efficacy of PIC-G4-DOX nanoparticles in killing MCF-7 breast cancer cells. Alteration in the expression levels of selected genes was determined …


Group Ii Introns : Evolution, Structure And Function, Xiaolong Dong Jan 2020

Group Ii Introns : Evolution, Structure And Function, Xiaolong Dong

Legacy Theses & Dissertations (2009 - 2024)

Group II introns are mobile, self-splicing ribozymes found in bacteria, archaea and eukaryotic organelles. They are widely believed to be the progenitors of the eukaryotic spliceosomal introns and retroelements. Yet many structural and evolutionary aspects of group II introns remain elusive. Indeed, while group II introns are the putative forerunners of spliceosomal introns in eukaryotes, they are notably absent in the nuclear genomes and a large portion of prokaryotes. Furthermore, although the architecture of a post-catalytic group II intron holoenzyme containing both the RNA and the bound intron encoded protein (IEP) has been solved by cryo-electron microscopy (cryo-EM), the interactions …


Neurodegenerative Modeling: Tau Protein, Degradative Pathways, And Gene Expression Profiling Of Human Ipsc-Derived Neural Precursors And Differentiated 3-D Neural Sphere Versus 2-D Monolayer Cultures, Kyle H. Anthoney Jan 2020

Neurodegenerative Modeling: Tau Protein, Degradative Pathways, And Gene Expression Profiling Of Human Ipsc-Derived Neural Precursors And Differentiated 3-D Neural Sphere Versus 2-D Monolayer Cultures, Kyle H. Anthoney

Cal Poly Humboldt theses and projects

Human induced pluripotent stem cells offer a model for human brain development and disease by differentiation into brain organoids; however, current neural culture systems lack the microenvironment, neuronal circuits and connectivity, vascular circulation, and immune system that exist in vivo. After differentiation and development of neuronal and non-neuronal cell types within two formats of cell cultures, we can visualize and recapitulate in vivo protein accumulation, gene expression, and degradative processes such as autophagy. Using RNA extraction, purification methods and reverse transcription I compared traditional monolayer cultures and novel 3-D neural sphere cultures via gene expression analysis. This analysis indicated …


Plasticity And The Impact Of Increasing Temperature On A Tropical Ectotherm, Adam A. Rosso Jan 2020

Plasticity And The Impact Of Increasing Temperature On A Tropical Ectotherm, Adam A. Rosso

Electronic Theses and Dissertations

Organisms may respond to climate change through behavior, genetic adaptation, and/or phenotypic plasticity. Tropical ectotherms are thought to be especially vulnerable to climate change because most have a narrow range of thermal tolerance while living close to their upper thermal tolerance limits. Additionally, many tropical species live in closed-canopy forests, which provide homogenous thermal landscapes that prevent behavioral compensation for stressfully warm temperatures. Finally, tropical ectotherms are thought to have decreased capacity for phenotypic plasticity because they have evolved in thermally stable environments. We tested gene expression patterns and phenotypic plasticity in the Panamanian slender anole by a) measuring changes …


Codon Bias And Mrna Folding Stability: Two Natural Controls Of Protein Expression Dynamics, Anastacia Wienecke Jan 2020

Codon Bias And Mrna Folding Stability: Two Natural Controls Of Protein Expression Dynamics, Anastacia Wienecke

WWU Graduate School Collection

Introduction: Connections between genetic variation and trait variation are complex and dynamic; the critical link between the two is gene expression variation. Though proteins are the functional products of most genes, the relative ease and throughput level of various measurement approaches has meant that gene expression is typically studied via transcript-level rather than protein-level techniques. Recent studies however, suggest that certain genetic factors act post-transcriptionally to modify rates of protein synthesis, making transcript levels imperfect indicators of protein levels. A gene’s bias for ‘optimal’ codons (i.e., its codon bias) and a gene’s mRNA folding stability appear to be two such …


Interspecific Gene Flow Potentiates Adaptive Evolution In A Hybrid Zone Formed Between Pinus Strobiformis And Pinus Flexilis, Mitra Menon Jan 2020

Interspecific Gene Flow Potentiates Adaptive Evolution In A Hybrid Zone Formed Between Pinus Strobiformis And Pinus Flexilis, Mitra Menon

Theses and Dissertations

Species range margins are often characterised by high degrees of habitat fragmentation resulting in low genetic diversity and higher gene flow from populations at the core of the species range. Interspecific gene flow from a closely related species with abutting range margins can increase standing genetic diversity and generate novel allelic combinations thereby alleviating limits to adaptive evolution in range margin populations. Hybridization driven interspecific gene flow has played a key role in the demographic history of several conifer due to their life history characteristics such as weak crossability barriers and long generation times. Nevertheless, demonstrating whether introgression is adaptive …