Genetics and Genomics Commons^™

Mutating Lysine 336 In Msh6 Does Not Appear To Affect Dna Mismatch Repair In Saccharomyces Cerevisiae, Anthony Thompson, Daniel Reese, Noa Bennafield, Kalila Daveron, Christopher Bolden, Joanna E. Haye-Bertolozzi

XULAneXUS

Defects in the DNA mismatch repair process results in the accumulation of mutations and disease. Mutations in MSH6 and MSH2, encoding for the subunits of the MutSα complex, are often responsible for Constitutional Mismatch Repair Deficiency (CMMRD) and Lynch Syndrome (LS), respectively. This work focused on DNA mismatch repair through analysis of the MSH6 missense variant msh6-K336T. The mutation examined in this study is msh6-K336T in Saccharomyces cerevisiae, which is equivalent to msh6-K431T in humans. The mutation results in the replacement of lysine with threonine, an amino acid with different properties. It was therefore hypothesized that the mutation …

The Study Of Dmrt1 In Zebrafish And How It Impacts Sex Determination, Raymond Michael Poirier

Graduate Masters Theses

The dmrt1 gene is common amongst most animals and functions to determine or maintain male sex during development. Similarly, in zebrafish dmrt1 is important for male sex determination and maintaining proper testis morphology. This gene is expressed in two different cell types of the testis in zebrafish, germ cells and Sertoli cells. While we know where this gene is expressed and what its role is, it is not known if it is sufficient to drive male fate. If so, then in which cells is it sufficient to drive male fate in the testis? I aimed to answer this question by …

Unravelling The Genetic Basis Of Schizophrenia, Clara Casey, John F. Fullard, Roy D. Sleator

Department of Biological Sciences Publications

Neuronal development is a highly regulated mechanism that is central to organismal function in animals. In humans, disruptions to this process can lead to a range of neurodevelopmental phenotypes, including Schizophrenia (SCZ). SCZ has a significant genetic component, whereby an individual with an SCZ affected family member is eight times more likely to develop the disease than someone with no family history of SCZ. By examining a combination of genomic, transcriptomic and epigenomic datasets, large-scale ‘omics’ studies aim to delineate the relationship between genetic variation and abnormal cellular activity in the SCZ brain. Herein, we provide a brief overview of …

A Case Of Incipient Budding Speciation In The California Floristic Province, Infraspecific Divergence In Abronia Villosa, Eli J. Allen

Cal Poly Humboldt theses and projects

Physical barriers to gene flow are the traditional evidence for species divergence. Conversely, there has been increasing acknowledgment of speciation in the face of gene flow as an evolutionary process. Budding speciation involves peripheral populations adapting to local ecological conditions, thereby budding off from a widespread progenitor species. Budding speciation is distinguished by ecological divergence and is generally evidenced by asymmetrical range size and nested phylogenetic relationships of sister species. The narrow endemic Abronia villosa var. aurita is adapted to montane sandy washes adjacent to its widespread sister variety, the desert dwelling var. villosa. Here, I tested the hypothesis …

Engaging Students In A Genetics Course-Based Undergraduate Research Experience Utilizing Caenorhabditis Elegans In Hybrid Learning To Explore Human Disease Gene Variants, Natalie Forte, Virginia Veasey, Bethany Christie, Amira Carter, Marli Hanks, Alan Holderfield, Taylor Houston, Anil Challa, Ashley Turner

Research, Publications & Creative Work

Genetic analysis in model systems using bioinformatic approaches provides a rich context for a concrete and conceptual understanding of gene structure and function. With the intent to engage students in research and explore disease biology utilizing the nematode Caenorhabditis elegans model, we developed a semester-long course-based undergraduate research experience (CURE) in a hybrid (online/in-person) learning environment—the gene-editing and evolutionary nematode exploration CURE (GENE-CURE). Using a combination of bioinformatic and molecular genetic tools, students performed structure-function analysis of disease-associated variants of uncertain significance (VUS) in human orthologs. With the aid of a series of workshop-style research sessions, students worked in teams …

Gonads Without Glp-1: Silencing Glp-1 In The Male Somatic Gonad In Caenorhabditis Elegans, Matthew Titus

Undergraduate Theses

In C. elegans, the gene glp-1 encodes for a Notch receptor called GLP-1, one of two found in C. elegans’ genome. The gene has been previously implicated in the development of the hermaphroditic germline as well as playing a role in the mitosis/meiosis decision. Genetic screening has further identified it as potentially playing a role in the development of the male somatic gonad, making it an ideal candidate for a reverse genetic. We did this by silencing glp-1 and observing if any alterations to the gonad’s phenotype occur.

Normally this could be done by performing a gene knockout. …

Understanding The Expression And Role Of Pros-1 In The Male Gonad Of C. Elegans, Jack Bozik

Undergraduate Theses

The gene pros-1 is a transcription factor that is highly expressed within neuronal sheath cells, glial cells, and excretory canal cells. pros-1 plays a role in cell determination of those cell types in the nematode C. elegans, which promotes organismal development. But the degree to which pros-1 presence is important is still not fully understood, because there are many genes involved in development that when mutated or damaged can result in unexpected phenotypes or even total loss of function to a certain developmental mechanism. What makes pros-1 valuable to research is that it is a functional homologue to a …

Molecular Investigation Of Minor Genomic Populations And Biological Exposures In Human Health, Brandon Ned Johnson

Dissertations and Theses

The study of genetics has contributed to countless discoveries related to human health and disease. However, the complexities of human biology reside not only in the genome but also in the contributions from environmental exposures, as measured via the classical twin design. To understand the influence of biological exposures, I implemented study designs to explore both the health associations and propagation of foreign genetic material. Microchimerism has been studied for association with several clinical conditions, and I further investigated if male microchimerism could elucidate the etiology of Mayer-Rokitansky-Küster-Hauser syndrome. Prevalence of male microchimerism in women with no history of pregnancy …

Ngly1 Deficiency Affects Glycosaminoglycan Biosynthesis And Wnt Signaling Pathway In Mice, Amy Batten

PANDION: The Osprey Journal of Research and Ideas

Individuals affected by NGLY1 Deficiency cannot properly deglycosylate and recycle certain proteins. Even though less than 100 people worldwide have been diagnosed with this rare autosomal recessive condition, thousands are affected by similar glycosylation disorders. Common phenotypic manifestations of NGLY1 Deficiency include severe neural and intellectual delay, impaired muscle and liver function, and seizures that may become intractable. Very little is currently known about the various mechanisms through which NGLY1 deficiency affects the body and this has led to a lack of viable treatment options for those afflicted. This experiment uses a loss-of-function (LOF) mouse model of NGLY1 Deficiency homologous …

My Summer Working With Two-Spotted Spider Mites, Renée A. Smith

Undergraduate Student Research Internships Conference

Two-spotted spider mites are a polyphagous pest, capable of eating a magnitude of food crops which causes a large problem for Canadian agriculture. Their ability to consume various crops stems from their ability to adapt to various chemical defence mechanisms. This ability allows them to acquire resistance to many commonly used pesticides. This has resulted in large infections in Canadian farms with few options to prevent the pests from affecting crop yields. Take a look at my project if you'd like to see how the Grbic lab is working to combat this issue using genetic engineering techniques!

Invasion Of The Northeastern United States By The Southern Pine Beetle, Dendroctonus Frontalis, And The Impacts On Signatures Of Isolation By Distance Assessed Using Mitochondrial Dna, Lora Grace Holman

Honors Theses

The southern pine beetle (SPB) is a small, black beetle that parasitizes pine trees across the United States and Central America. Recently it has been recognized that the range of SPB is not limited to the southern United States, but rather extends northward across the eastern United States, which raises concerns for pine trees that have never encountered the pest before. Using mitochondrial DNA sequences from a section of the cytochrome oxidase I gene and four different measures of genetic distance compared to geographic distance, we tested for evidence of isolation by distance (IBD) among sampled SPB to see whether …

Invisible Disabilities, Academic Capital And Competitiveness Of Genetic Counseling Applicants, Natalie E. Stoner, Meagan Choates, Carla Mcgruder, Debra Murray, Theresa Wittman, Sara Wofford, Claire N. Singletary

Dissertations & Theses (Open Access)

The field of genetic counseling has historically lacked diversity. Recent research has begun to explore how visible diversity may present barriers to a genetic counseling applicant becoming competitive, but has not yet characterized potential barriers with invisible diversities, such as being a first-generation college student, or a part of the LBGTQ+ community. Therefore, this study aimed to address this gap among those with invisible diversities, as well as explore their academic capital (AC), a theoretical framework used to identify factors that make students more likely to succeed in post-secondary work including supportive networks, trustworthy information, family uplift, college knowledge, overcoming …

The Role And Regulation Of The Caudal Gene In Tribolium Castaneum Segmentation, Suzanne Nicole Carpe Elias

Senior Theses and Projects

The embryo of the red flour beetle Tribolium castaneum develops sequentially by adding segments in an anterior-to-posterior progression using a “clock”-like mechanism similar to that of vertebrates. Previous studies indicate that the oscillations of this segmentation clock are driven by a gradient of the transcription factor caudal (cad), which activates and regulates the clock. Knocking down the cad gene using parental or early embryonic RNAi leads to animals with only head segments. We hypothesized that progressively later embryonic knockdowns would produce animals with progressively more segments if the function of cad does not change during segmentation. To examine …

Mutant Kras Alters Extracellular Vesicle Microrna Sorting In Pancreatic Cystic Neoplasms, Rachel L. Dittmar

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers by organ site with a 5-year survival rate of just 10.8%. This is largely because most patients do not experience symptoms until the disease has already metastasized. The best hope to cure PDAC is surgery, which can only be done with a curative intent at an early stage when the disease is localized. There are no reliable circulating, body-fluid-based biomarkers to detect early stage PDAC or its precursor lesions in a timely manner for effective surgical intervention. When potential PDAC precursor lesions, such as mucinous pancreatic cysts are found, there are …

The Effects Of Ppal-1 In Arabidopsis Gamete Development, Amanda J White, Susana Perez-Martinez, Mark P. Running

The Cardinal Edge

Prenylation is a type of post-translational modification in which a 15- or 20-carbon lipid is added to the carboxyl (C) terminus of the protein. Arabidopsis thaliana contains the PROTEIN PRENYLTRANSFERASE ALPHA SUBUNIT-LIKE (PPAL) gene, which encodes a protein with homology to the α-subunits of the three known prenylation enzymes, PFT, PGGT, and Rab-GGT. We previously identified two mutations in PPAL, one of which is ppal-1, which contains a T-DNA insertion in the fourth intron. We have previously observed that self-fertilizing heterozygous ppal-1 plants produce progeny in which homozygous ppal-1 is underrepresented. This project attempts to ascertain …

You Are What You Eat — Exploring The Microbiome Through Inquiry-Based Labs. Microbiome Lesson Plans, Karla S. Fuller

Open Educational Resources

If these commonly used spices have the ability to inhibit pathogenic bacterial growth, could they also potentially inhibit the growth of normal, harmless bacteria that live in your body? In this lab, we will test common bacteria for resistance to food additives.

Changes In Gene Sequence That Cause Discordances Involving Disease In Monozygotic Twins, Kacie Jacques

Thinking Matters Symposium

Identical twins or, monozygotic twins, occur when the egg in a mother is fertilized, but one zygote divides into two separate embryos. Monozygotic twins are considered to be genetically identical, but most twins often display discordances, some involving diseases or disorders. Some of these differences are due to environmental factors. For example, one twin may have diabetes due to diet. Recent literature has shown that some differences in monozygotic twins may be due to changes in gene sequence, as opposed to random, environmental or epigenetic factors. Identical twins from pedigrees with familial disease often show discordances. When looking at schizophrenia …

The Evolution Of Mimicry; The Doublesex Gene, Aisha Hill

Thinking Matters Symposium

Many butterfly species use mimicry in order to increase their chance of survival. In Batesian mimicry, non toxic butterflies mimic the wing patterns, colors, and shapes of another species that is toxic to predators. Swallowtail butterflies (Papilio polytes) are well-known Batesian mimics, and also display sexual dimorphism with distinct differences between the sexes. Sex limited mimicry is common. The female butterfly may mimic an inedible red-bodied swallowtail, such as the common rose (Pachliopta aristolochiae), or she may be non-mimetic. The male butterfly is non-mimetic. This is a review of recent research into the origin and evolution …

Examining A Functional Interaction Between Chromatin Remodeler Chd1 And Histone H1 In D. Melanogaster, Breanna Kim

Scripps Senior Theses

Chromodomain-helicase-DNA-binding-protein-1 (CHD1) is a highly conserved ATP- dependent remodeling protein. It is localized to active genes and directs nucleosome spacing, while its loss has been linked to various human diseases, such as human prostate cancer. In Drosophila, CHD1 is important for fertility and wing development, and overexpression of CHD1 leads to severe wing vein defect phenotypes. The Linker Histone H1, which is known for maintaining heterochromatin and is associated with inactive genes, had been previously identified as a possible functional partner of CHD1, though the exact nature of their interaction is unclear. I undertook a genetic approach to examining the …

Composition And Homology In The Taxonomic Classification Of Escherichia Coli, Tanya Irani

Theses and Dissertations (Comprehensive)

As new techniques have been introduced, specifically the possibility of complete genome sequencing, better methods of defining bacterial species have also been proposed. One of the most recently proposed methods, using bioinformatic techniques, is to calculate the average nucleotide identity (ANI) between the homologous genome segments of different isolates. Another method for species discrimination that has been tested successfully is the similarity of DNA compositional signatures. However, in a recent update, DNA signatures split the available Escherichia coli complete genomes into three groups. To check if this result was consistent with such genomes belonging to different species, we tested methods …

A Cophylogenetic Analysis Of Fungus Gardening Ants And Their Symbiotic Fungi, Katherine Beigel

Biology Theses

Fungus-growing ants (Tribe Attini) and their fungal cultivars share a 50-million-year coevolutionary history. Large scale phylogenetic analyses depict a strong co-phyletic signal among ants and their farmed fungi yet fungus sharing among unrelated ant lineages is somewhat widespread. An overview of sharing has been hampered by a lack of genetic markers that exhibit intraspecific variation and surveys across geographic regions. For example, previous studies have shown similar sequences of the internal transcribed spacer (ITS) region of fungus in different species of Trachymyrmex, suggesting that these ant species are farming the same fungal clone. To examine whether this was a …

The Design And Validation Of A Qpcr-Based Approach To Cell Quantification Of Fungal-Algal Symbioses, Isabelle Katherine Garlotte

Honors Theses

Symbiotic relationships are extremely common in virtually all species. These relationships between organisms, particularly mutualistic symbioses, can have an incredibly large impact and can greatly affect the evolution of the species involved. Of particular interest is the suspected mutualistic relationship between green algae and fungi that may hold key evidence of how terrestrial plants evolved. In this experiment we established a method of quantifying the cells of each species involved in these symbioses through qPCR analysis to determine if the relationships are truly mutualistic. We developed a system for using DNA copies as a proxy for cell count in co-cultures …

Connections In The Underworld: A Morphological And Molecular Study Of Diversity And Connectivity Among Anchialine Shrimp., Robert Eugene Ditter

FIU Electronic Theses and Dissertations

This research investigates the distribution and population structure of crustaceans, endemic to anchialine systems in the tropical western Atlantic focusing on cave-dwelling shrimp from the family Barbouriidae. Taxonomic and molecular tools (genetic and genomic) are utilized to examine population dynamics and the presence of phenotypic hypervariation (PhyV) of the critically endangered species Barbouria cubensis (von Martens, 1872). The presence of PhyV and its geographic distribution is investigated among anchialine populations of B. cubensis from 34 sites on Abaco, Eleuthera, and San Salvador, Bahamas. Examination of 54 informative morphological characters revealed PhyV present in nearly 90% (n=463) of specimens with no …

Identification And Characterization Of Novel Genes And Genetic Interactions That Influence Iba Metabolism, Vanessica Jawahir

Dissertations

Indole-3-butyric acid (IBA) is an endogenous storage auxin important for maintaining appropriate indole-3-acetic acid (IAA) levels that influences primary root elongation and lateral root development. IBA is metabolized into free IAA in the peroxisome in a multistep process similar to fatty acid β-oxidation. Although many components specific to IBA metabolism and peroxisome function have been identified, our understanding is incomplete. I sought to identify novel components of IBA metabolism or peroxisome function by conducting a forward genetic screen for Arabidopsis thaliana plants with enhanced resistance to IBA. I identified Long chain acyl-CoA synthetase 4 (LACS4) as a novel gene functioning …

Identifying Positive Selection In Multiple Subspecies Of Xylella Fastidiosa, Daniel Doroteo Flores

Theses and Dissertations

For this study, we will be looking to identify positive selection in eight genomes of the bacterial plant pathogen Xylella fastidiosa. A previous study used a branching method that identified 2 genes with positive selection along with a site-specific method identifying 34 genes showing positive selection. This current study focused specifically on the site-specific method, resulting in 28 genes (of 1,039 tested) showing positive selection. Of the 28 genes showing positive selection, 12 of them come from the pathogenicity, virulence and cellular structural categories. The remaining genes are found in the biosynthesis, metabolism, macro metabolism, and cellular process categories. …

Determining The Genetic Control Of Neural Tube Malformation Through Genetic Interactions With Idgf3, Elli N. Fox

Honors Projects

Genetic mutations disrupting human neural tube formation can lead to birth defects such as spina bifida and anencephaly. Defects can result in lack of neural tube closure in either the caudal (spina bifida) or cranial (anencephaly) regions. Little is known about the genes that cause these malformations. Researchers have been using the model organism Drosophila melanogaster in an attempt to determine genes responsible for neural tube malformations. Recently, an ortholog of human chitin-like protein, imaginal disc growth factor 3 (Idgf3), has been identified as important in the proper formation of Drosophila egg dorsal appendages. However, the molecular mechanism responsible for …

Population Genetics Of A Recent Range Expansion By The Southern Pine Beetle, Dendroctonus Frontalis, Into The Northeastern United States, Megan Stubbs

Honors Theses

Population genetics as a field of study aims to determine the genetic variation among individuals in a population, and differences among populations. Certain population genetic analyses can provide such information and be used to better understand the biological aspects to a species’ expansion beyond its native range. The southern pine beetle (SPB), Dendroctonus frontalis, has become an invasive pest to pine forests in northeastern United States with its recent range expansion. Nine microsatellite loci were first developed and then used in analyses. To determine what the genetic variation is among individuals in SPB populations across its entire range, including …

Genetic Analysis Of Flower Color Differences Between A Hummingbird-Pollinated And A Self-Pollinated Monkeyflower (Mimulus) Species, Caitlin Foster

University Scholar Projects

Flower color plays an important role in pollinator discrimination and speciation. Understanding the genetic contributions to flower color differences between two closely related species, Mimulus cardinalis and Mimulus parishii, can improve understanding of how they developed different pollination syndromes and diverged from a recent common ancestor. M. cardinalis is hummingbird-pollinated and has large, bright red flowers while M. parishii is self-pollinated and has small, pale pink flowers. An F2 hybrid population between these two species was created to establish a platform for analysis of the genetic architecture controlling the differences in anthocyanin pigmentation. Statistical analysis of anthocyanin concentration distribution …

A Look At Gene Control: Tracking The Ccnd1 Gene, Bryan Anders

Mahurin Honors College Capstone Experience/Thesis Projects

Cancer occurs when the cell does not properly control its own cell cycle. It then replicates in an out of control fashion leading to the death of various organs and then the demise of the organism as a whole. As it seems to have always been a problem for cell-based life, certain safeguards against cancer have been evolved over time. One such method comes in the form of prevention via cyclin proteins, which are encoded from cyclin genes. The gene that is the focus of this research is the CCND1, or cyclin D1, gene that controls the progression through various …

Using Crispr-Cas9 As A Restriction Enzyme, Zack Crawley

Master's Theses

Restriction digests are a commonly utilized process for cleaving DNA at specific, but relatively common sites. Restriction enzymes have widespread use in DNA manipulation. CRISPR/Cas9 is a recently identified endonuclease which utilizes a customizable guide sequence to recognize and cut specific ~20 bp sites located in a DNA sequence. This preliminary research aimed to exploit the potential benefit of DNA restriction using the CRISPR/Cas9 procedure through alterations of different components involved in that system. We sought to refine existing CRISPR/Cas9 protocols and make a budget friendly, user-selectable CRISPR/Cas9 restriction digest protocol. The motivation for this research was to simplify and …