Molecular and Cellular Neuroscience Commons^™

Roles Of Autism Gene Arid1b In Murine Brain Development And Behavior, Amanda L. Smith

Theses & Dissertations

Autism spectrum disorder (ASD) and intellectual disability (ID) are highly prevalent neurodevelopmental disorders characterized by social and communication deficits, stereotyped behaviors, cognitive dysfunction, and deficits in adaptive behaviors. The pathogenesis underlying these disorders remains unknown, and thus no pharmacologic or genetic therapies are currently available. Recent progress in the field has shown that haploinsufficiency of the AT-rich interactive domain-containing 1B (ARID1B) gene is a genetic cause of ASD and ID. Our lab recently developed an Arid1b knockout mouse model to better study its role in the pathogenesis of these disorders. One theory regarding the cause of neurodevelopmental disorders …

The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth

Graduate Theses and Dissertations

Axons in the developing embryo receive and react to signals that direct their growth to reach target tissues at specified locations. The signal pathways that direct midline crossing of axons during embryonic development have been comprehensively examined in the past years using the Drosophila ventral nerve cord or the spinal cord as a model system. A number of these signaling mechanisms are conserved, however disparities have been found between species in general strategy or the molecular signals controlling the response of axons to guidance cues.

The Netrin-Frazzled pathway has been shown to aid in midline crossing of axons in the …

Notch Inhibitors And The Bet Inhibitor Jq-1 Decrease The Growth Of Primary Tumor Cells Derived From A Novel Mouse Model Of C11orf95-Rela Induced Brain Tumor, Ericka Randazzo, Jesse Dunnack, Justin Fang, Joseph Loturco Phd

University Scholar Projects

Brain tumors are the most common childhood solid malignancy, and because of remarkable advances in treating many cancers outside of the brain, they have become the leading cause of cancer mortality in children. Ependymomas are a class of brain tumors which can be further subdivided into three groups based upon their location and genetic features. Of the three classes, supratentorial ependymomas are the only subgroup known to be marked by an oncogenic driver gene, which consists of a fusion mutation between the C11orf95 and RELA genes. C11orf95-RELA positive tumors are the most aggressive and lethal of …

The 5-Ht1a-R Knockout Mouse As A Model Of Later Life Anxiety Disorders: Implications For Sex Differences, Tatyana Budylin

Dissertations, Theses, and Capstone Projects

Anxiety affects nearly twice as many women as it affects men across all cultures and economic groups. Importantly, girls have a higher chance of inheriting anxiety disorders than boys, and many anxiety disorders appear at a very young age. However, little is known about sex differences in brain and behavioral development and how they relate to anxiety in adulthood. Serotonin 1A receptor (5-HT_1A-R) mediated signaling has been implicated in depression and anxiety, however most studies that focus on the involvement of the 5-HT_1A-R have been conducted in adults. Little is known about how the 5-HT_{1A …}

A Novel Kinesin Adapter Directly Mediates Dendritic Mrna Localization During Synapse Development, Hao Wu

Dissertations, Theses, and Capstone Projects

Cytoskeleton based active transport with motor proteins is essential for mRNA localization and local protein translation in animal cells, yet how mRNA granules interact with motor proteins remains poorly understood. Using an unbiased screen for interaction between mRNA binding proteins (RBP) and motor proteins, we identified protein interacting with APP tail 1 (PAT1) as a potential direct adapter between the β-actin mRNA Zipcode-binding protein 1 (ZBP1) and Kinesin-1 motor complex.

Mouse PAT1 is similar to the Kinesin Light Chain (KLC) in amino acid sequence and binds directly to KLC. High-resolution images from structured illumination microscopy (SIM) indicates that synaptic stimulation …

The Role Of Ash1l During Human Neurodevelopment, Anna Bagnell

Senior Theses

Autism spectrum disorders (ASD) are associated with defects in neuronal connectivity and are highly heritable. A significant proportion of ASD cases are of complex genetic etiology; complexity which might reflect the impact of gene-environment interactions. However, there is a gap in our understanding of the mechanisms that underlie the gene-environment interaction in autism complex etiology. Genome wide association studies in large ASD cohorts identified high risk variants associated with autism in genes that regulate histone modifications and remodel chromatin. These findings highlight the relevance of chromatin regulatory mechanisms in the pathology of ASD. Changes in Histone H3 methylation have been …

The Drosophila Neuroblasts: A Model System For Human Ribosomopathies, Sonu Shrestha Baral

LSU Doctoral Dissertations

This dissertation describes the use of Drosophila neuroblasts (NBs) to model human ribosomopathies; the overall goal is to understand why specific stem cell and progenitor cell populations are the primary targets in nucleolar stress as seen in the ribosomopathies. Chapter 1 provides an overview of relevant literature. Chapter 2 describes nucleolar stress in Drosophila neuroblasts as a model for human ribosomopathies. For this, we induce nucleolar stress by using the UAS-GAL4 system to express RNAi that depletes Nopp140 transcripts, and we also employ homozygous, CRISPR-Cas9-generated Nopp140 gene disruptions with a systemic null phenotype (Nopp140-/-). Embryonic lethality was observed …

The Integration Of Multiple Sources Of Sonic Hedgehog In The Spinal Cord Contribute To The Production Of First-Born Oligodendrocyte Precursor Cells Which Become Critical For Synapse Remodeling In Response To Adult Motor Neuron Injury, Lev Starikov

Dissertations, Theses, and Capstone Projects

Oligodendrocyte precursor cells (OPCs) arise sequentially first from a ventral and then from a dorsal precursor domain during spinal cord development. Whether the sequential production of OPCs is of physiological significance has not been examined. Here I show that interrupting Sonic hedgehog (Shh) signaling originating from nascent ventricular zone derivatives (VZD), motor neurons and the lateral floor plate, almost completely blocks ventral but not dorsal oligodendrogenesis without noticeably affecting early tissue patterning and embryonic development. In the absence of ventral OPCs, dorsal OPCs increase proliferation and populate the entire spinal cord with increased density. In these mutant mice, dOPCs take …

Molecular Analysis Of Cone Photoreceptor Genesis From A Specific Retinal Progenitor Population, Diego F. Buenaventura

Dissertations, Theses, and Capstone Projects

There are two types of photosensitive cells of the retina that contribute to image formation: Cone photoreceptors that mediate color discrimination and rods that provide photosensitivity in low-light conditions. Given the importance of cones in high acuity and color vision, deficiencies in this cell type that result from ailments such as retinitis pigmentosa and macular degeneration can lead to a debilitating loss of vision. Currently, one of the most pressing goals in the field of retinal development is the elucidation of the gene regulatory networks (GRN) involved in inducing an undifferentiated cell into becoming a functional cone photoreceptor.

Recently, an …

Spag17 Deficiency Impairs Neuronal Cell Differentiation In Developing Brain, Olivia J. Choi

Theses and Dissertations

The development of the nervous system is a multi-level, time-sensitive process that relies heavily on cell differentiation. However, the molecular mechanisms that control brain development remain poorly understood. We generated a knockout (KO) mouse for the cilia associated gene Spag17. These animals develop hydrocephalus and enlarged ventricles consistent with the role of Spag17 in the motility of ependymal cilia. However, other phenotypes that cannot be explained by this role were also present. Recently, a mutation in Spag17 has been associated with brain malformations and severe intellectual disability in humans. Therefore, we hypothesized that Spag17 plays a crucial role in …