Molecular Biology Commons^™

Polymeric Sumo-2/3 Chain Signals Are Antagonistically Regulated By The Sumo-Targeted Ubiquitin E3 Ligase Rnf4 And The Sumo-Specific Isopeptidase Senp6, Shaniah A. Irving M.A., Xiang-Dong Zhang Ph.D.

Biology Theses

Polymeric SUMO-2/3 chain modification is critical for chromosome segregation, DNA damage repair, genome stability, stress responses, and protein degradation. However, how these signals are regulated remains poorly understood. Both the SUMO-targeted ubiquitin E3 ligase (STUbL) RNF4 and the SUMO-specific isopeptidase SENP6 recognize poly-SUMO-2/3 chains through multiple SUMO-interacting motifs (SIMs). RNF4 contains four tandem SIMs within a short (~80 amino acids) region, whereas SENP6 possesses eight SIMs spanning a much larger (~500 amino acids) domain.

Our preliminary results show that overexpressing an RNF4 N-terminal fragment containing four tandem SIMs (wild type, WT), but not an inactive SIMs mutant (Mut), increases levels …

Traittrainr: Accelerating Large-Scale Simulation Under Models Of Continuous Trait Evolution, Jenniffer Roa Lozano, Mataya Duncan, Duane D. Mckenna, Todd A. Castoe, Michael Degiorgio, Richard Adams

Entomology and Plant Pathology Faculty Publications and Presentations

Abstract

The scale and scope of comparative trait data are expanding at unprecedented rates, and recent advances in evolutionary modeling and simulation sometimes struggle to match this pace. Well-organized and flexible applications for conducting large-scale simulations of evolution hold promise in this context for understanding models and more so our ability to confidently estimate them with real trait data sampled from nature. Results

We introduce TraitTrainR, an R package designed to facilitate efficient, large-scale simulations under complex models of continuous trait evolution. TraitTrainR employs several output formats, supports popular trait data transformations, accommodates multi-trait evolution, and exhibits flexibility …

The Effects Of Mosaicism On Biological And Clinical Markers Of Alzheimer's Disease In Adults With Down Syndrome, Laura Xicota, Lam-Ha T. Dang, Alice Lee, Sharon Krinsky-Mchale, Deborah Pang, Lisa Melilli, Sid E. O’Bryant, Rachel L. Henson, Charles Laymon, Florence Lai, H. Diana Rosas, Beau Ances, Ira Lott, Christy Hom, Bradley Christian, Sigan Hartley, Shahid Zaman, Elizabeth Head, Mark Mapstone, Zhezhen Jin, Wayne Silverman, Nicole Schupf, Benjamin Handen, Joseph H. Lee, Alzheimer’S Biomarker Consortium – Down Syndrome (Abc-Ds)

Neurology Faculty Publications

Background Individuals with Down syndrome (DS) are at high risk of early-onset Alzheimer’s disease (AD); yet, some 20 percent do not develop any signs of dementia until after 65 years or in their lifetime. Mosaicism could contribute to this phenotypic variation, where some disomic cells could lead to lower levels of gene products from chromosome 21.

Methods We examined longitudinal neuropsychological and biomarker data from two large studies of DS: the Alzheimer Biomarker Consortium–Down syndrome study (ABC-DS) (n = 357); and a legacy study (n = 468). We assessed mosaicism using karyotyping or GWAS data. Participants had data on plasma …

Targeted Long-Read Sequencing To Quantify Methylation Of The C9orf72 Repeat Expansion, Evan Udine, Nicole Finch, Mariely Dejesus-Hernandez, Jazmyne L. Jackson, Matthew C. Baker, Siva Arumugam Saravanaperumal, Eric Wieben, Mark T. W. Ebbert, Jaimin Shah, Leonard Petrucelli, Rosa Rademakers, Björn Oskarsson, Marka Van Blitterswijk

Neurology Faculty Publications

Background The gene C9orf72 harbors a non-coding hexanucleotide repeat expansion known to cause amyotrophic lateral sclerosis and frontotemporal dementia. While previous studies have estimated the length of this repeat expansion in multiple tissues, technological limitations have impeded researchers from exploring additional features, such as methylation levels.

Methods We aimed to characterize C9orf72 repeat expansions using a targeted, amplification-free long-read sequencing method. Our primary goal was to determine the presence and subsequent quantification of observed methylation in the C9orf72 repeat expansion. In addition, we measured the repeat length and purity of the expansion. To do this, we sequenced DNA extracted from …

Encapsulation Of Probiotics By Cellulose Nanocrystal-Alginate Composite Beads For Ph Stimuli-Responsive Delivery, Akrip Jati

Graduate Theses and Dissertations

Microencapsulation has garnered significant interest, with oral probiotics delivery systems showing enormous potential to help restore the gut microbiome. This method holds vast potential to protect and release specific microbial strains to the desired target site (i.e., colon) within the gastrointestinal tract (GIT). However, current encapsulation methodologies, utilizing either synthetic or biological materials as carriers, encounter challenges such as suboptimal encapsulation efficiency, premature probiotic release, and inadequate control over release kinetics. In this work, hydrogel microsphere (HM) composites of different cellulose nanocrystal (CNC) forms (i.e., colloidal (c), and crosslinked (x)) and alginate (ALG) were used as advanced controlled release systems …

Independent Evolution Of Oleate Hydratase Clades In Bacillales Reflects Molecular Convergence, Robert J. Neff, Priscilla C. Lages, Shannon K. Donworth, James D. Brien, Christopher D. Radka

Markey Cancer Center Faculty Publications

Oleate hydratase (OhyA), a flavoenzyme that catalyzes the hydration of unsaturated fatty acids, has been identified in various Bacillales organisms, including those in the Listeria, Lysinibacillus, Paenibacillus, and Staphylococcus genera. In this study, we combine structural biology with molecular and phylogenetic analyses to investigate the evolutionary dynamics of the OhyA protein family within the Bacillales order. Our evolutionary analysis reveals two distinct OhyA clades (clade I and clade II) within Bacillales that, while sharing catalytic function, exhibit significant genomic and structural differences. Our findings suggest that these OhyA clades originated from independent evolutionary processes through convergent evolution rather than gene …

Assessing The Temporal Role Of Mir-200 Loss In Murine Models Of Nsclc, Jared Fradette

Dissertations and Theses (Open Access)

Lung cancer is the leading cause of cancer related deaths in the United States, with non-small cell lung cancer (NSCLC) making up a majority of new diagnoses. Metastasis is the big killer in NSCLC and is driven by epithelial-mesenchymal transition (EMT) and immune evasion. The microRNA 200 family is a master regulator of EMT and is implicated in immune regulation. In this study we have developed a novel genetically engineered mouse model (GEMM) and derived primary cell lines from them to explore the role of microRNA-200 in early EMT and immune changes. Our model combines conditional activation of Kras^{G12D …}

Cross-Interactions Of Amyloid Proteins: Implications For Aggregation Dynamics And Disease Pathology, Zhiyuan Song

All Dissertations

Amyloid aggregation is a pervasive form of protein misfolding implicated in the pathology of several prominent human diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and type 2 diabetes (T2D). These diseases are marked by the accumulation of amyloid fibrils and toxic oligomers, which are highly dynamic and heterogeneous, posing challenges for understanding their roles in disease progression. Despite significant advances in the diagnosis and management of these conditions, no definitive cure is available. We investigate amyloid aggregation and cross-seeding, with a focus on amyloid-beta (Aβ), tau, alpha-synuclein (αS), and human islet amyloid polypeptide (IAPP) through discrete molecular dynamics (DMD) …

Integrated Transcriptomics And Proteomics Study Of Starvation Selected Drosophila Melanogaster, Aavash Adhikari

UNLV Theses, Dissertations, Professional Papers, and Capstones

Drosophila melanogaster, selected for starvation resistance exhibits phenotypic traits such as increased body size, slower development, reduced fecundity and obesity like characteristics including higher lipid reserves and cardiac dysfunction. While prior studies have explored the metabolic and biochemical changes in these flies, the underlying genetic and molecular mechanisms remain unclear. This study aims to investigate the gene expression and protein abundance in starvation-selected Drosophila through RNAseq, proteomics, and integrating both datasets using the MixOmics package in R. I found differential gene expression in the fat body at the third instar larval stage, particularly in pathways related to lipid metabolism, calcium …

Ecological And Pathological Applications Of The Heat Shock Response, Taylor Rae Stanley

Theses and Dissertations

The heat shock response (HSR) is a cytoprotective stress response pathway that regulates cellular proteostasis. The HSR is an evolutionarily conserved pathway that is essential for normal cellular functioning. Here, we explore the broad ecological and pathological impacts of the HSR. In an ecological context, we perform gene level analysis of the transcriptomes of two closely related sunfish. We found that the more invasive bluegill sunfish has gene expansions in two HSR gene families, the HSP70 family and the HSP90 family compared to the redear sunfish. These gene expansions were also observed in several other teleost fish species and were …

Characterization Of An Acetogenin-Carrying Nanosuspension And Its Effect On Bacteria Of Interest In The Poultry Industry, Brandon A. Lopez-Romero, Gabriela Aguilar-Hernandez, Billy M. Hargis, Maria De Lourdes Garcia-Magana, Ulises M. Lopez-Garcia, Rosa I. Ortiz-Basurto, Adalberto Zamudio-Ojeda, Juan D. Latorre, Efigenia Montalvo-Gonzalez

Poultry Science Faculty Publications and Presentations

This work aimed to develop a nanosuspension (NSps) as an acetogenin (ACGs) carrier, using soy lecithin (SL) and hydroxypropyl-β-cyclodextrin (βCD) named NSps-βCDSL-ACGs. It was characterized by various spectroscopic techniques (DLS, FTIR, UV-vis diffuse reflectance). Moreover, the NSps morphology was observed by transmission electron microscopy (TEM). Also, the antibacterial activity of NSps-βCDSL-ACGs was evaluated against strains of interest in the poultry sector. NSps-βCDSL-ACGs presented nanometric size (207–239 nm), acceptable polydispersity index (PDI) values (0.13–0.17) and a high Z potential value (−47.17–50.36 mV), demonstrating high stability. The presence of ACGs in NSps-βCDSL-ACGs was confirmed by FTIR analysis. The nanoparticles had a spherical …

Decoding Fgf/Fgfr Signaling: Insights Into Biological Functions And Disease Relevance, Oshadi Edirisinghe, Gaetane Ternier, Zeina Alraawi, Thallapuranam Krishnaswamy Suresh Kumar

Chemistry & Biochemistry Faculty Publications and Presentations

Fibroblast Growth Factors (FGFs) and their cognate receptors, FGFRs, play pivotal roles in a plethora of biological processes, including cell proliferation, differentiation, tissue repair, and metabolic homeostasis. This review provides a comprehensive overview of FGF-FGFR signaling pathways while highlighting their complex regulatory mechanisms and interconnections with other signaling networks. Further, we briefly discuss the FGFs involvement in developmental, metabolic, and housekeeping functions. By complementing current knowledge and emerging research, this review aims to enhance the understanding of FGF-FGFR-mediated signaling and its implications for health and disease, which will be crucial for therapeutic development against FGF-related pathological conditions.

Investigation Of Reproductive Inhibition During Chronic Heat Stress In C. Elegans, Macy Makenna Nielander

Theses and Dissertations

Nearly all organisms experience heterogeneity in environmental conditions that can negatively impact fitness. A common adaptive strategy to reduce the impact of this stress is called facultative diapause, where development and reproduction are temporarily arrested to promote survival. Facultative diapause is characterized by three major criteria, the arrest must be (i) induced by an unfavorable environmental condition, (ii) reversible, and (iii) driven by genetically regulated mechanisms. The aim of this thesis was to determine whether chronic heat-induced inhibition of egg laying in Caenorhabditis elegans represents a novel form of facultative diapause. It was found that the inhibition of egg-laying is …

Cd46 Is A Protein Receptor For Human Adenovirus Type 64, Eugene Y. Wu, Alexander M. Robertson, Hanglin (Henry) Zhu, Corina Stasiak, Laura A. Murray-Nerger, Emily Romanoff, Jesse Woon, Beth A. Bromme, Jason G. Smith

Biology Faculty Publications

Certain species D human adenoviruses (HAdV-D19, -D37, and -D64) are causative agents of epidemic keratoconjunctivitis. HAdV-D37 has previously been shown to bind CD46 (membrane cofactor protein) and sialic acid as adhesion receptors. HAdV-D64 is genetically highly similar to HAdV-D37, with an identical fiber protein sequence, but differs substantially in its penton base and hexon proteins, two other major capsid components, due to genetic recombination. Here, we demonstrate that, like HAdV-D37, HAdV-D64 virions bind directly to CD46 and that CD46 and sialic acid also function as receptors for HAdV-D64 on multiple cell types. Expression of CD46 on CD46-negative cells conferred susceptibility …

Assessing The Bioactivity Of Salvia Phytochemicals Against Breast Cancers, Allison C. Portaro, Jared L. Scott, David J. Schultz

The Cardinal Edge

Breast cancer is one of the most common cancers diagnosed in adults, with 2.3 million new cases worldwide in 2020. Plants have been used in traditional medicine and are a potential source of pharmaceuticals. One example is the large Lamiaceae (mint) family. The Salvia genus, commonly known as the sages, is the largest genus in Lamiaceae with almost 900 known species. Different species of salvia are found in parts of the US, and some have a history in traditional medicine to treat cancers and other ailments. Preliminary research on three salvia species (S. lyrata, S. lyrata var. Purple …

Dysfunction Of Polyamine Metabolism In Down Syndrome Related To Cellular Senescence And Β-Amyloid Production, Andres D. Sola

Electronic Theses and Dissertations

Polyamines (PA) are ubiquitous in cells and highly involved in several important cellular functions and thus the dysregulation of their biosynthetic pathway is potentially associated with the progression of age-related diseases like Alzheimer’s’ disease (AD). Though there is research describing how PA content changes in organisms as they age or in those experiencing rapid aging from increased rates of senescence, as in Down syndrome (DS), it is not clear how this connection occurs and whether modulating this pathway may reveal downstream effects on related disease progression. This study examines how the modulation of the PA biosynthetic pathway by inhibition of …

Evaluating Human Plasma Biomakers For Alzheimer's Disease; Phosphorylated-Tau 217, Phosphorylated-Tau 181, And Glial Fibrillary Acidic Protein, Mason Jonah, Mayarae N. Mugosa, Bella Hou, Emma-Nikole Krilchev, Zhengshi Yang, Dietmar Cordes, Aaron Ritter, Jefferson W. Kinney

Undergraduate Research Symposium Posters

Alzheimer’s Disease (AD) is a progressive neurodegenerative disease that is primarily identifiable by amyloid-beta (Aβ) neuronal plaques, neurofibrillary tangles (NFT) that form as aggregates of hyperphosphorylated tau (ptau) proteins clump together, and the presence of neuroinflammation; all of which are otherwise known as the hallmarks of AD pathology. Recent emerging research has discovered striking similarities between AD and diabetes mellitus pathology, illustrating how insulin deficiency and insulin resistance–both of which result in the chronic hyperglycemic state seen in the diabetic–are involved in an increase in the phosphorylation of tau. This leads to and intensifies the formation of intracellular NFTs serving …

Therapeutic Potential Of Astrocyte-Derived Extracellular Vesicles In Mitigating Cytotoxicity And Transcriptome Changes In Human Brain Endothelial Cells, Ruth Juliana Stewart

Doctoral Dissertations

Extracellular vesicles (EVs) play a major role in cell-to-cell communication via the horizontal transfer of RNA, DNA, proteins, and lipids that affect the physiological response of the recipient cells. Astrocytes are a type of glial cell that exerts a protective effect on neurons and brain endothelial cells. The astrocytes and the endothelial cells form the blood-brain barrier. Due to their nano-size and non-complex structure, EVs can efficiently cross the blood-brain barrier. This study investigated and assessed the impact of EVs on reducing oxidative DNA damage in human brain endothelial cells (HBECs). The protective potential of astrocyte-derived EVs was determined by …

Genome-Guided Isolation Of The Hyperthermophilic Aerobe Fervidibacter Sacchari Reveals Conserved Polysaccharide Metabolism In The Armatimonadota, Nancy O. Nou, Jonathan K. Covington, Dengxun Lai, Xavier Mayali, Cale O. Seymour, Juliet Johnston, Jian-Yu Jiao, Steffen Buessecker, Damon Mosier, Alise R. Muok, Nicole Torosian, Allison M. Cook, Ariane Briegel, Tanja Woyke, Emiley Eloe-Fadrosh, Nicole Shapiro, Scott G. Bryan, Savannah Sleezer, Joshua Dimapilis, Cristina Gonzalez, Lizett Gonzalez, Marlene Noriega, Matthias Hess, Ross P. Carlson, Lan Liu, Meng-Meng Li, Zheng-Han Lian, Siqii Zhu, Fan Liu, Xian Sun, Beile Gao, Ritesh Mewalal, Miranda Harmon-Smith, Ian K. Blaby, Jan-Fang Cheng, Peter K. Weber, Gabriela Grigorean, Wen-Jun Li, Anne E. Dekas, Jennifer E. Pett-Ridge, Jeremy A. Dodsworth, Marike Palmer, Brian P. Hedlund

Life Sciences Faculty Research

Few aerobic hyperthermophilic microorganisms degrade polysaccharides. Here, we describe the genome-enabled enrichment and optical tweezer-based isolation of an aerobic polysaccharide-degrading hyperthermophile, Fervidibacter sacchari, previously ascribed to candidate phylum Fervidibacteria. F. sacchari uses polysaccharides and monosaccharides for growth at 65–87.5 °C and expresses 191 carbohydrate-active enzymes (CAZymes) according to RNA-Seq and proteomics, including 31 with unusual glycoside hydrolase domains (GH109, GH177, GH179). Fluorescence in-situ hybridization and nanoscale secondary ion mass spectrometry confirmed rapid assimilation of 13C-starch in spring sediments. Purified GHs were optimally active at 80–100 °C on ten different polysaccharides. Finally, we propose reassigning Fervidibacteria as a class …

The Divergent Responses Of Salinity Generalists To Hyposaline Stress Provide Insights Into The Colonisation Of Freshwaters By Diatoms, Kathryn J. Judy, Eveline Pinseel, Kala M. Downey, Jeffrey A. Lewis, Andrew J. Alverson

Biological Sciences Faculty Publications and Presentations

Environmental transitions, such as the salinity divide separating marine and fresh waters, shape biodiversity over both shallow and deep timescales, opening up new niches and creating opportunities for accelerated speciation and adaptive radiation. Understanding the genetics of environmental adaptation is central to understanding how organisms colonise and subsequently diversify in new habitats. We used time-resolved transcriptomics to contrast the hyposalinity stress responses of two diatoms. Skeletonema marinoi has deep marine ancestry but has recently invaded brackish waters. Cyclotella cryptica has deep freshwater ancestry and can withstand a much broader salinity range. Skeletonema marinoi is less adept at mitigating even mild …