Developmental Biology Commons^™

Regulation Of Intracellular Sorting Of The Bruno Protein In Drosophila Flight Muscles, Travis Main

Master's Theses

Understanding mechanisms of intracellular sorting is a fundamental inquiry of cell biology. We used the B-body and protein Bruno (Bru) as a model to study the formation of nuclear domains that are membraneless organelles inside the cell nucleus. Specifically, we sought to identify protein sequences that regulate Bru's affinity to B-bodies and protein aggregation. We generated various Bru mutants and subsequently tested them in vivo using fluorescence microscopy. We found that the protein solubility of Bru is determined through an interplay of RNA recognition motifs (RRMs) and intrinsically disordered regions (IDRs). Using truncation analysis, we identified a 31-amino acid region …

The Role Of Akirin/Nurd Interactions During Heart Development, Mia Jones

Symposium of Student Scholars

Congenital heart defects are often identified during pregnancy or infancy and are the most common birth defect presented in humans, affecting blood circulation resultant from small holes in a blood chamber to deformity-inducing missing structures. Recent advancements in medicine have allowed those affected to live healthier, longer lives. Gene combinations and chromosomal changes play pivotal roles in congenital heart defects, but the specific genes involved remain unknown. The Nowak Lab has discovered several novel regulatory proteins that are critical for embryonic heart development and is studying them for a potential link to congenital heart defects.

During embryogenesis, the heart of …

Spr-5; Met-2 Maternal Reprogramming Cooperates With The Dream Complex To Regulate Developmental Cell Fates, Jazmin Dozier, Sandra Nguyen, Brandon Carpenter

Symposium of Student Scholars

Histone methylation is a post-transcriptional modification to the N-terminal tails of histone core proteins that regulates DNA accessibility, and consequently, gene expression. Like DNA, histone methylation can be inherited between generations, and is highly regulated during embryonic development. At fertilization, histone methylation must undergo maternal reprogramming to reset the epigenetic landscape in the new zygote. During maternal reprogramming of histone methylation in the nematode, C. elegans, H3K4me (a modification associated with active transcription) is removed by the H3K4 demethylase, SPR-5, and H3K9me (a modification associated with transcriptional repression) is subsequently added by the histone methyltransferase, MET-2. Recently, it was …

Identification Of Phenotypic Defects In The Zinc Finger Transcription Factor Ztf-29, Trae Dunn

Symposium of Student Scholars

Aging and many aging-associated diseases such as Alzheimer’s disease and cancer are characterized by a progressive decline in physiological functions and a decline in the ability to respond to stress. The underlying causes for many aging-associated diseases are unknown. Identifying genes that control normal aging will advance our understanding of the molecular changes that underlie the aging process and might help treat age-associated diseases. In order to get a better understanding of the molecular mechanisms behind these diseases, we utilize the nematode Caenorhabditis elegans as a model organism to examine defects in physiology and aging.

The human PRDM genes code …

Temperature Changes Seen In Lower Extremities After Cpn Local Anesthetic Block, Lora Asberry

Symposium of Student Scholars

Many older patients often suffer from walking issues such as Drop Foot. Drop Foot is caused by the malfunction of nerves in the foot, resulting in the loss of control of the front foot muscle. Within all of our patients, there has been a common fibular palsy, caused by the entrapment of the peroneal nerve. Due to this, they cannot lift up their foot. Some cases are permanent, while others are temporary. In the temporary cases, we have indicated a Phoenix Sign. The Phoenix Sign indicates that a nerve, presumed to be dead, has the capability to be recessed back …

Analysis Of The Role Of Akirin Interactions With Nuclear Body Proteins During Myogenesis, Laura Yorke

Master of Science in Integrative Biology Theses

Akirin is a highly conserved, small nuclear protein of indeterminate structure ubiquitously expressed in non-fungal eukaryotic species. It was first discovered in the innate immune response, but many other functions have since been found, including embryonic muscle patterning and myogenesis. Animals with either nonfunctional or missing Akirin have aberrations in embryonic muscle patterning, along with other defects. Akirin interacts with transcription factors such as Twist to coordinate development through interfacing between Twist and other complexes, such as the Brahma Chromatin Remodeling Complex (BRM). Therefore, Akirin likely plays a general role in transcription during early development, interfacing with other transcriptional machinery …

Creating A Protein Chimera To Study Regulation Of Muscle Diversity, Shannon Scarboro

Symposium of Student Scholars

Creating a protein chimera to study regulation of muscle diversity.

Body muscles are made of many individual super-cells, called muscle fibers, that have distinct properties and determine every individual’s strength and endurance. Initially all muscle fibers have identical characteristics, but become differentiated into specific types in adults. The mechanism of such transition is not well understood, despite its obvious importance for shaping human physicality.

Remarkable conservation of the muscle tissue enables us to use fruit flies to study the mechanisms of muscle fiber diversity. We hypothesized that the transcription factor Mef2 acts as a molecular switch that activates structural genes …

Using A Novel Cell- Penetrating Peptide Technology To Induce Pluripotency, Laura-Maria Oja

Master of Science in Chemical Sciences Theses

Somatic stem cells have been used as a regenerative medicine tool to treat diseases like leukemia for decades, but they are limited in their ability to self-renew and differentiate. A better alternative, induced pluripotent stem cells (iPSCs), has the ability to generate cells from all three germ layers and avoid tissue rejection as well as bypass the ethical concerns related to embryonic stem cells. In 2006, Takahashi and Yamanaka discovered that only four genes were required to induce pluripotency: Oct4, Sox2, Klf4, and c-Myc (OSKM). Since then, pluripotency has been induced with OSKM most effectively by transfection or transduction. However, …

Investigating The Molecular Function Of Akirin During Skeletal Myogenesis In Drosophila Melanogaster, Kristina Rowland

Master of Science in Integrative Biology Theses

The specification and differentiation of muscle precursor cells, or myoblasts, by the action of the mesodermal and muscle transcription regulator Twist is a key event in the formation of the Drosophila larval musculature. Akirin, a highly conserved nuclear protein, appears to play a critical role in the regulation of Twist-dependent gene expression during mesodermal specification and muscle development. Specifically, Akirin serves as a cofactor to promote interactions between regulatory transcription factors and multisubunit Brahma SWI/SNF-class chromatin remodeling complex to impact gene expression across varying targets. Using a genetic interaction screen in Drosophila, we have begun to identify other Akirin …

Electrosensory Ampullary Organs Are Derived From Lateral Line Placodes In Bony Fishes, Melissa S. Modrell, William E. Benis, R. Glenn Northcutt, Marcus C. Davis, Clare V.H. Baker

Faculty Articles

Electroreception is an ancient subdivision of the lateral line sensory system, found in all major vertebrate groups (though lost in frogs, amniotes and most ray-finned fishes). Electroreception is mediated by 'hair cells' in ampullary organs, distributed in fields flanking lines of mechanosensory hair cell-containing neuromasts that detect local water movement. Neuromasts, and afferent neurons for both neuromasts and ampullary organs, develop from lateral line placodes. Although ampullary organs in the axolotl (a representative of the lobe-finned clade of bony fishes) are lateral line placode-derived, non-placodal origins have been proposed for electroreceptors in other taxa. Here we show morphological and molecular …