Medicine and Health Sciences Commons^™

Ontogenetic Scaling Patterns And Functional Anatomy Of The Pelvic Limb Musculature In Emus (Dromaius Novaehollandiae), Luis P. Lamas, Russell P. Main, John R. Hutchinson

Department of Basic Medical Sciences Faculty Publications

Emus (Dromaius novaehollandiae) are exclusively terrestrial, bipedal and cursorial ratites with some similar biomechanical characteristics to humans. Their growth rates are impressive, as their body mass increases eighty-fold from hatching to adulthood whilst maintaining the same mode of locomotion throughout life. These ontogenetic characteristics stimulate biomechanical questions about the strategies that allow emus to cope with their rapid growth and locomotion, which can be partly addressed via scaling (allometric) analysis of morphology. In this study we have collected pelvic limb anatomical data (muscle architecture, tendon length, tendon mass and bone lengths) and calculated muscle physiological cross sectional area …

Subcellular Metabolite And Lipid Analysis Of Xenopus Laevis Eggs By Laesi Mass Spectrometry, Bindesh Shrestha, Prabhakar Sripadi, Brent R. Reschke, Holly D. Henderson, Matthew J. Powell, Sally Ann Moody, Akos Vertes

Anatomy and Regenerative Biology Faculty Publications

Xenopus laevis eggs are used as a biological model system for studying fertilization and early embryonic development in vertebrates. Most methods used for their molecular analysis require elaborate sample preparation including separate protocols for the water soluble and lipid components. In this study, laser ablation electrospray ionization (LAESI), an ambient ionization technique, was used for direct mass spectrometric analysis of X. laevis eggs and early stage embryos up to five cleavage cycles. Single unfertilized and fertilized eggs, their animal and vegetal poles, and embryos through the 32-cell stage were analyzed. Fifty two small metabolite ions, including glutathione, GABA and amino …

Asynchronous Remodeling Is A Driver Of Failed Regeneration In Duchenne Muscular Dystrophy, Sherry Dadgar, Zuyi Wang, Helen Johnston, Akanchha Kesari, Kanneboyina Nagaraju, Yi-Wen Chen, D. Ashley Hill, Terence A. Partridge, Robert J. Freishtat, Javad Nazarian, Jianhua Xuan, Yue Wang, Eric P. Hoffman

Genomics and Precision Medicine Faculty Publications

We sought to determine the mechanisms underlying failure of muscle regeneration that is observed in dystrophic muscle through hypothesis generation using muscle profiling data (human dystrophy and murine regeneration). We found that transforming growth factor β-centered networks strongly associated with pathological fibrosis and failed regeneration were also induced during normal regeneration but at distinct time points. We hypothesized that asynchronously regenerating microenvironments are an underlying driver of fibrosis and failed regeneration. We validated this hypothesis using an experimental model of focal asynchronous bouts of muscle regeneration in wild-type (WT) mice. A chronic inflammatory state and reduced mitochondrial oxidative capacity are …

Neural Transcription Factors: From Embryos To Neural Stem Cells, Hyun-Kyung Lee, Hyun-Shik Lee, Sally Ann Moody

Anatomy and Regenerative Biology Faculty Publications

The early steps of neural development in the vertebrate embryo are regulated by sets of transcription factors that control the induction of proliferative, pluripotent neural precursors, the expansion of neural plate stem cells, and their transition to differentiating neural progenitors. These early events are critical for producing a pool of multipotent cells capable of giving rise to the multitude of neurons and glia that form the central nervous system. In this review we summarize findings from gain- and loss-of-function studies in embryos that detail the gene regulatory network responsible for these early events. We discuss whether this information is likely …

Large-Scale Identification Of Chemically Induced Mutations In Drosophila Melanogaster., Nele A Haelterman, Lichun Jiang, Yumei Li, Vafa Bayat, Hector Sandoval, Berrak Ugur, Kai Li Tan, Ke Zhang, Danqing Bei, Bo Xiong, Wu-Lin Charng, Theodore Busby, Adeel Jawaid, Gabriela David, Manish Jaiswal, Koen J T Venken, Shinya Yamamoto, Rui Chen, Hugo J Bellen

Faculty Publications

Forward genetic screens using chemical mutagens have been successful in defining the function of thousands of genes in eukaryotic model organisms. The main drawback of this strategy is the time-consuming identification of the molecular lesions causative of the phenotypes of interest. With whole-genome sequencing (WGS), it is now possible to sequence hundreds of strains, but determining which mutations are causative among thousands of polymorphisms remains challenging. We have sequenced 394 mutant strains, generated in a chemical mutagenesis screen, for essential genes on the Drosophila X chromosome and describe strategies to reduce the number of candidate mutations from an average of …

Regulation Of Mammary Gland Development And Tumorigenesis By 14-3-3 Zeta, Sumaiyah Rehman

Dissertations & Theses (Open Access)

Signaling pathways that play critical roles in organ development are often aberrantly regulated during cancer initiation and progression. 14-3-3z is overexpressed in more than 40% of breast cancers and is associated with poor patient prognosis. Therefore, the function of 14-3-3z in cancer and normal mammary gland development was investigated utilizing multiple in vivo and in vitro approaches. 14-3-3z is a chaperone protein that interacts with a multitude of oncogenes and tumor suppressor genes, thereby functioning as a critical node in multiple oncogenic signaling networks. Mammary gland-specific 14-3-3z transgenic mouse models showed that 14-3-3z overexpression was sufficient to induce mammary tumorigenesis. …

Characterization Of Ftsa-Ftsn Interaction During Escherichia Coli Cell Division, Kimberly.Busiek@Gmail.Com K. Busiek

Dissertations & Theses (Open Access)

Division of a bacterial cell into two equal daughter cells requires precise assembly and constriction of the division machinery, or divisome. The Escherichia coli divisome includes nearly a dozen essential cell division proteins that assemble at midcell between segregating sister chromosomes. FtsZ, a homolog of eukaryotic tubulin, is the first essential cell division protein to localize at midcell where it polymerizes into a ring-shaped scaffold (Z ring). Establishment of the Z ring is required for recruitment of downstream cell division proteins including FtsA, a cytoplasmic protein that tethers the Z ring to the inner membrane. Following localization of FtsA and …

The Grass Shrimp, Palaemonetes, Pugio: Hypoxic Influences On Embryonic Development, Christensen C. Javier

UNLV Theses, Dissertations, Professional Papers, and Capstones

Grass shrimp,Palaemonetes pugio, can survive in brackish waters and estuarine ecosystems despite the frequent oscillations and fluctuations in salinity, temperature and oxygen. AdultP. pugiohave the ability to osmoregulate (Romney and Reiber 2011), change cardiac parameters to tolerate temperatures (not yet published, Mika and Reiber) and oxyregulate (Guadagnoli and Reiber 2013). Manipulation of cardiac parameters allows for these methods of regulation. However, cardiac contraction and internal convection of oxygen do not occur until later stages of embryonic development. Studies focused on these morphological and physiological advantages may provide further understanding of the regulatory mechanisms within grass shrimp embryos, larvae and adults. …

Photobiostimulation In C. Elegans As A Model For Low Level Light Therapy, Michael J. Spoto, Daryl D. Hurd

Science Scholars

Low-Level Laser Therapy (LLLT) is a developing therapeutic technique that has been gaining recognition in the scientific community in recent years. Previous experiments performed in LLLT research projects have been primarily mammalian and cell culture based. These experiments have produced results showing accelerated tissue repair. In this experiment, we introduce a new model, Caenorhabitidis elegans, a free-living soil nematode, to be used in LLLT research by testing the effects of exposure of the organism to various wavelengths and intensities of light commonly used in LLLT. C. elegans was shown to respond to photobiostimulation when exposed to specific wavelengths of …

A Central Role For Vimentin In Regulating Repair Function During Healing Of The Lens Epithelium, A. S. Menko, B. M. Bleaken, A. A. Libowitz, L. Zhang, Mary Ann Stepp, J. L. Walker

Anatomy and Regenerative Biology Faculty Publications

Mock cataract surgery provides a unique ex vivo model for studying wound repair in a clinically relevant setting. Here wound healing involves a classical collective migration of the lens epithelium, directed at the leading edge by an innate mesenchymal subpopulation of vimentin-rich repair cells. We report that vimentin is essential to the function of repair cells as the directors of the wound-healing process. Vimentin and not actin filaments are the predominant cytoskeletal elements in the lamellipodial extensions of the repair cells at the wound edge. These vimentin filaments link to paxillin-containing focal adhesions at the lamellipodial tips. Microtubules are involved …

Paracrine-Rescued Lobulogenesis In Chimeric Outgrowths Comprising Progesterone-Receptor-Null Mammary Epithelium And Redirected Wild-Type Testicular Cells, Robert D. Bruno, Corinne A. Boulanger, Sonia M. Rosenfield, Lisa H. Anderson, John P. Lydon, Gilbert H. Smith

School of Medical Diagnostics & Translational Sciences Faculty Publications

We have previously shown that non-mammary and tumorigenic cells can respond to the signals of the mammary niche and alter their cell fate to that of mammary epithelial progenitor cells. Here we tested the hypothesis that paracrine signals from mammary epithelial cells expressing progesterone receptor (PR) are dispensable for redirection of testicular cells, and that re-directed wild-type testicular-derived mammary cells can rescue lobulogenesis of PR-null mammary epithelium by paracrine signaling during pregnancy. We injected PR-null epithelial cells mixed with testicular cells from wild-type adult male mice into cleared fat-pads of recipient mice. The testicular cells were redirected in vivo to …

Mouse Oocyte Maturation And Embryo Development After Exposure To Vemurafenib (Plx4032), An Anti-Melanoma B-Raf V600e Inhibitor, Bo Liu

Theses and Dissertations in Biomedical Sciences

Vemurafenib is a selective B-Raf^V600E inhibitor in melanoma targeted therapy which also inhibits the wild type B- and C-Raf. In oocyte maturation, the C-Raf/MAPK pathway acts as an important self-enhancing and promoting system, w hereas in embryo development, the C-Raf/M APK pathway participates in pre- and post- implantation embryo proliferation and differentiation.

The hypothesis: Vemurafenib has detrimental effects on oocyte maturation and/or embryo development. Mouse oocytes and one cell (1C) mouse embryos were tested by ex vivo culturing with Vemurafenib in serial dilution. Oocytes were evaluated by cell cycle morphology, spindle formation and chromosomal alignment by im munofluorescence (IF) …