Cell and Developmental Biology Commons^™

Il-15 Activates The Jak3/Stat3 Signaling Pathway To Mediate Glucose Uptake In Skeletal Muscle Cells, James E. Krolopp, Shantaé M. Thornton, Marcia J. Abbott

Health Sciences and Kinesiology Faculty Articles

Myokines are specialized cytokines that are secreted from skeletal muscle (SKM) in response to metabolic stimuli, such as exercise. Interleukin-15 (IL-15) is a myokine with potential to reduce obesity and increase lean mass through induction of metabolic processes. It has been previously shown that IL-15 acts to increase glucose uptake in SKM cells. However, the downstream signals orchestrating the link between IL-15 signaling and glucose uptake have not been fully explored. Here we employed the mouse SKM C2C12 cell line to examine potential downstream targets of IL-15-induced alterations in glucose uptake. Following differentiation, C2C12 cells were treated overnight with 100 …

Comparative Genetic Screens In Human Cells Reveal New Regulatory Mechanisms In Wnt Signaling, Andres M. Lebensohn, Ramin Dubey, Leif Neitzel, Ofelia Tacchelly-Benites

Dartmouth Scholarship

The comprehensive understanding of cellular signaling pathways remains a challenge due to multiple layers of regulation that may become evident only when the pathway is probed at different levels or critical nodes are eliminated. To discover regulatory mechanisms in canonical WNT signaling, we conducted a systematic forward genetic analysis through reporter-based screens in haploid human cells. Comparison of screens for negative, attenuating and positive regulators of WNT signaling, mediators of R-spondin-dependent signaling and suppressors of constitutive signaling induced by loss of the tumor suppressor adenomatous polyposis coli or casein kinase 1α uncovered new regulatory features at most levels of the …

Sirt1 Regulates Glial Progenitor Proliferation And Regeneration In White Matter After Neonatal Brain Injury., Beata Jablonska, Marcin Gierdalski, Li-Jin Chew, Teresa Hawley, Mackenzie Catron, Arturo Lichauco, Juan Cabrera-Luque, Tracy Yuen, David Rowitch, Vittorio Gallo

Pediatrics Faculty Publications

Regenerative processes in brain pathologies require the production of distinct neural cell populations from endogenous progenitor cells. We have previously demonstrated that oligodendrocyte progenitor cell (OPC) proliferation is crucial for oligodendrocyte (OL) regeneration in a mouse model of neonatal hypoxia (HX) that reproduces diffuse white matter injury (DWMI) of premature infants. Here we identify the histone deacetylase Sirt1 as a Cdk2 regulator in OPC proliferation and response to HX. HX enhances Sirt1 and Sirt1/Cdk2 complex formation through HIF1α activation. Sirt1 deacetylates retinoblastoma (Rb) in the Rb/E2F1 complex, leading to dissociation of E2F1 and enhanced OPC proliferation. Sirt1 knockdown in culture …

The Fate Of Icd-1 During Misfolded Protein Induced Apoptosis In Caenorhabditis Elegans, Kyle H. Perez

Senior Honors Projects, 2010-2019

Severe misfolded protein stress initiates cellular responses that often result in the death of the affected cell, typically by apoptosis. An essential aspect of apoptosis is caspase-mediated cleavage of proteins that, once cleaved, further propagate death. One heterodimeric structure putatively targeted in this process in the nascent polypeptide-associated complex (NAC), a translational chaperone thought to help prevent misfolded protein stress in the ER. The purpose of this investigation was to determine whether the beta subunit of the NAC in C. elegans (ICD-1) is cleaved during the induction of apoptosis, with the hypothesis that ICD-1 is cleaved during stressed-induced apoptosis to …

Changes In Mitochondrial Homeostasis And Redox Status In Astronauts Following Long Stays In Space, Hiroko P. Indo, Hideyuki J. Majima, Masahiro Terada, Shigeaki Suenaga, Kazuo Tomita, Shin Yamada, Akira Higashibata, Noriaki Ishioka, Takuro Kanekura, Ikuya Nonaka, Clare L. Hawkins, Michael J. Davies, Daret K. St Clair, Chiaki Mukai

Toxicology and Cancer Biology Faculty Publications

The effects of long-term exposure to extreme space conditions on astronauts were investigated by analyzing hair samples from ten astronauts who had spent six months on the International Space Station (ISS). Two samples were collected before, during and after their stays in the ISS; hereafter, referred to as Preflight, Inflight and Postflight, respectively. The ratios of mitochondrial (mt) to nuclear (n) DNA and mtRNA to nRNA were analyzed via quantitative PCR. The combined data of Preflight, Inflight and Postflight show a significant reduction in the mtDNA/nDNA in Inflight, and significant reductions in the mtRNA/nRNA ratios in both the Inflight and …

A Cloud-Based Workflow To Quantify Transcript-Expression Levels In Public Cancer Compendia, P J. Tatlow, Stephen R. Piccolo

Faculty Publications

Public compendia of sequencing data are now measured in petabytes. Accordingly, it is infeasible for researchers to transfer these data to local computers. Recently, the National Cancer Institute began exploring opportunities to work with molecular data in cloud-computing environments. With this approach, it becomes possible for scientists to take their tools to the data and thereby avoid large data transfers. It also becomes feasible to scale computing resources to the needs of a given analysis. We quantified transcript-expression levels for 12,307 RNA-Sequencing samples from the Cancer Cell Line Encyclopedia and The Cancer Genome Atlas. We used two cloud-based configurations and …

Defining The Role Of Phosphorylation And Dephosphorylation In The Regulation Of Gap Junction Proteins, Hanjun Li

Theses & Dissertations

Gap junctions are intercellular channels that permit the free passage of ions, small metabolites, and signaling molecules between neighboring cells. In the diseased human heart, altered ventricular gap junction organization and connexin expression (i.e., remodeling) are key contributors to rhythm disturbances and contractile dysfunction. Connexin43 (Cx43) is the dominant gap junction protein isoform in the ventricle which is under tight regulation by serine/tyrosine phosphorylation. Phosphorylation and dephosphorylation regulate many aspects of Cx43 function including trafficking, assembly and disassembly, electrical and metabolic coupling at the plaque, as well as to modulate the interaction with other proteins.

Serine phosphorylation has long been …

Regulation Of Alteration/Deficiency In Activation 3 (Ada3) By Acetylation And Its Role In Cell Cycle Regulation And Oncogenesis, Shashank Srivastava

Theses & Dissertations

The ADA3 (Alteration/Deficiency in Activation 3) protein is a transcriptional adaptor protein that was initially discovered as a component of several HAT (Histone Acetyltransferase) complexes, the enzyme complex responsible for histone acetylation, which is a prerequisite for transcription. Earlier the studies from Dr. Band’s laboratory and that of others’ have deciphered a crucial role of ADA3 in cell cycle regulation (both through G₁/S and G₂/M phase transitions) and in maintaining the genomic stability.

While our laboratory investigated the mechanism behind the role of ADA3 in G₁/S transition, the same remained unknown for G_{2 …}

Role Of Cbl-Family Ubiquitin Ligases As Critical Negative Regulators Of T Cell Activation And Functions, Benjamin Goetz

Theses & Dissertations

Adaptive T cell immunity is essential for defense against foreign antigens and immune surveillance against cancer. Tight regulation of T cell activation is required to avoid autoimmunity to self-antigens or protracted inflammation after foreign antigens are cleared. Incomplete or inappropriate stimulation leads to an active shutdown of T cell activation called anergy. The Casitas B-lineage Lymphoma (CBL)-family of ubiquitin ligases (E3s) are essential negative regulators of T cell activation that impinge on thymic selection as well as anergy induction programs. Single gene studies show that CBL is critical during T cell development while CBL-B plays an essential role in peripheral …

Mitogen And Morphogen Signaling Dysregulation: Pathophysiological Influence In Pancreatic Cancer And Alzheimer’S Disease, Eric Cruz

Theses & Dissertations

Although the etiology of a particular disease will vary, there are genetic and epigenetic bottlenecks that frequently converge resulting in dysregulation of mitogenic and morphogenetic signaling. This propensity is acutely experienced in malignancy and neurodegenerative disease.

Here, we have first investigated the role of dysregulated signaling in the context of pancreatic cancer (PC). Morphogenetic signaling has been regarded as a pleiotropic pathway with the potential to promote and inhibit metastatic features. Our investigation of bone morphogenetic protein 2 (BMP-2), an archetypical member of the BMP superfamily, has revealed the presence of extracellular, intracellular, and long non-coding RNA products. Our findings …

Fibroblast Growth Requires Ct10 Regulator Of Kinase (Crk) And Crk-Like (Crkl)., Taeju Park, Mateusz Koptyra, Tom Curran

Manuscripts, Articles, Book Chapters and Other Papers

CT10 regulator of kinase (Crk) and Crk-like (CrkL) are the cellular counterparts of the viral oncogene v-Crk Elevated levels of Crk and CrkL have been observed in many human cancers; inhibition of Crk and CrkL expression reduced the tumor-forming potential of cancer cell lines. Despite a close relationship between the Crk family proteins and tumorigenesis, how Crk and CrkL contribute to cell growth is unclear. We ablated endogenous Crk and CrkL from cultured fibroblasts carrying floxed alleles of Crk and CrkL by transfection with synthetic Cre mRNA (synCre). Loss of Crk and CrkL induced by synCre transfection blocked cell proliferation …

Biophysical And Functional Characterization Of Rhesus Macaque Igg Subclasses, Austin W. Boesch, Nana Yaw Osei-Owusu, Andrew R. Crowley, Thach H. Chu, Ying Chan, Joshua Weiner, Pranay Bharadwaj, Rufus Hards, Mark Adamo, Scott Gerber, Sarah Cocklin, Joern Schmitz, Adam Miles, Joshua Eckman, Aaron J. Belli, Keith Reimann, Margaret E. Ackerman

Dartmouth Scholarship

Antibodies raised in Indian rhesus macaques [Macaca mulatta (MM)] in many preclinical vaccine studies are often evaluated in vitro for titer, antigen-recognition breadth, neu- tralization potency, and/or effector function, and in vivo for potential associations with protection. However, despite reliance on this key animal model in translation of promising candidate vaccines for evaluation in first in man studies, little is known about the proper- ties of MM immunoglobulin G (IgG) subclasses and how they may compare to human IgG subclasses. Here, we evaluate the binding of MM IgG1, IgG2, IgG3, and IgG4 to human Fc gamma receptors (FcγR) and their …

Microtubule Actin Cross-Linking Factor 1, A Novel Target In Glioblastoma, Najlaa Afghani, Toral Mehta, Jialiang Wang, Nan Tang, Omar Skalli, Quincy A. Quick

Biology Faculty Research

Genetic heterogeneity is recognized as a major contributing factor of glioblastoma resistance to clinical treatment modalities and consequently low overall survival rates. This genetic diversity results in variations in protein expression, both intratumorally and between individual glioblastoma patients. In this regard, the spectraplakin protein, microtubule actin cross-linking factor 1 (MACF1), was examined in glioblastoma. An expression analysis of MACF1 in various types of brain tumor tissue revealed that MACF1 was predominately present in grade III-IV astroctyomas and grade IV glioblastoma, but not in normal brain tissue, normal human astrocytes and lower grade brain tumors. Subsequent genetic inhibition experiments showed that …

The Study Of The Functions And Regulation Of Mammalian Cap1 (Cyclase-Associated Protein 1), Haitao Zhang

Student Theses and Dissertations

CAP is a conserved actin-binding protein with versatile roles in promoting actin dynamics across species. Mammalian CAPs had been understudied compared to the first identified yeast homologues; their cellular functions remained to be better established. Moreover, CAP function regulation remained a completely uncharted area. Recent studies also implicated CAP in the invasiveness of human cancers. However, some of the evidence was not convincing and further studies were needed. The present study established and identified new cellular functions for mammalian CAP1, identified a regulatory mechanism as phosphorylation at the S307/S309 tandem site along with the cell signals controlling both phosphorylation and …

A Novel Rrm3 Function In Restricting Dna Replication Via An Orc5-Binding Domain Is Genetically Separable From Rrm3 Function As An Atpase/Helicase In Facilitating Fork Progression, Salahuddin Syed, Claus Desler, Lene J Rasmussen, Kristina H Schmidt

Molecular Biosciences Faculty Publications

In response to replication stress cells activate the intra-S checkpoint, induce DNA repair pathways, increase nucleotide levels, and inhibit origin firing. Here, we report that Rrm3 associates with a subset of replication origins and controls DNA synthesis during replication stress. The N-terminal domain required for control of DNA synthesis maps to residues 186-212 that are also critical for binding Orc5 of the origin recognition complex. Deletion of this domain is lethal to cells lacking the replication checkpoint mediator Mrc1 and leads to mutations upon exposure to the replication stressor hydroxyurea. This novel Rrm3 function is independent of its established role …

Calcium-Mediated Actin Reset (Caar) Mediates Acute Cell Adaptations, Pauline Wales, Christian Schuberth, Roland Aufschnaiter, Johannes Fels, Ireth Garcia-Aguilar, Annette Janning, Christopher D. Dlugos, Marco Schaefer-Herte, Christoph Klingner, Mike Waelte, Julian Kuhlmann, Ekaterina Menis, Hockaday Kang Hockaday Kang, Kerstin C. Maier, Wenya Hou, Antonella Russo, Henry N. Higgs

Dartmouth Scholarship

Actin has well established functions in cellular morphogenesis. However, it is not well understood how the various actin assemblies in a cell are kept in a dynamic equilibrium, in particular when cells have to respond to acute signals. Here, we characterize a rapid and transient actin reset in response to increased intracellular calcium levels. Within seconds of calcium influx, the formin INF2 stimulates filament polymerization at the endoplasmic reticulum (ER), while cortical actin is disassembled. The reaction is then reversed within a few minutes. This Calcium-mediated actin reset (CaAR) occurs in a wide range of mammalian cell types and in …

Hnrnpa2 Is A Novel Histone Acetyltransferase That Mediates Mitochondrial Stress-Induced Nuclear Gene Expression, Manti Guha, Satish Srinivasan, Kip Guja, Edison Mejia, Miguel Garcia-Diaz, F. Brad Johnson, Gordon Ruthel, Brett A. Kaufman, Eric F. Rappaport, M. Rebecca Glineburg, Ji-Kang Fang, Andres J. Klein-Szanto, Hiroshi Nakagawa, Jeelan Basha, Tapas Kundu, Narayan G. Avadhani

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Reduced mitochondrial DNA copy number, mitochondrial DNA mutations or disruption of electron transfer chain complexes induce mitochondria-to-nucleus retrograde signaling, which induces global change in nuclear gene expression ultimately contributing to various human pathologies including cancer. Recent studies suggest that these mitochondrial changes cause transcriptional reprogramming of nuclear genes although the mechanism of this cross talk remains unclear. Here, we provide evidence that mitochondria-to-nucleus retrograde signaling regulates chromatin acetylation and alters nuclear gene expression through the heterogeneous ribonucleoprotein A2 (hnRNAP2). These processes are reversed when mitochondrial DNA content is restored to near normal cell levels. We show that the mitochondrial stress-induced …

Punctuated Evolution Within A Eurythermic Genus (Mesenchytraeus) Of Segmented Worms: Genetic Modification Of The Glacier Ice Worm F1f0 Atp Synthase, Shirley A. Lang

Graduate School of Biomedical Sciences Theses and Dissertations

Segmented worms (Annelida) are among the most successful animal inhabitants of extreme environments worldwide. An unusual group of Mesenchytraeus worms endemic to the Pacific Northwest of North America occupy geographically proximal ecozones ranging from low elevation temperate rainforests to high altitude glaciers. Along this altitudinal transect, Mesenchytraeus representatives from disparate habitat types were collected and subjected to deep mitochondrial and nuclear phylogenetic analyses. Evidence presented here employing modern bioinformatic analyses (i.e., maximum likelihood, Bayesian inference, multi-species coalescent) supports a Mesenchytraeus “explosion” in the upper Miocene (5-10 million years ago) that gave rise to ice, snow and terrestrial worms, derived from …

Nucelotide Substitution Rates In Hantavirus Cd8+ T-Cell Epitopes, Brian Gerald Sikes

Graduate Theses

Hantaviruses pathogenic to humans are exclusive to rodents. Typically each hantavirus is associated with only one host species. Due to their close association, the geographical distributions are the same. Old World species, such as Hantaan hantavirus and Puumala hantavirus, induce symptoms described as the Hemorrhagic Fever with Renal Syndrome (HFRS). The New World hantaviruses, such as Andes hantavirus and Sin Nombre hantavirus, share a suite of symptoms that have been described as Hantavirus Pulmonary Syndrome (HPS). In this study, 16 well-characterized cytotoxic T lymphocytes (CTL) epitopes of the nucleocapsid (N) protein were identified from the literature.

These 16 …

Establishing A Novel Culture System Using 3d Printing To Induce Osteogenesis In Mc3t3-E! Osteoblasts, Lisa Carder

Graduate Theses

Whole organ tissue engineering represents a potential solution to the problem of organ shortage and host rejection; however, the process of producing a three-dimensional, functional organ is extremely complex. Research has used three-dimensional printing in order to combat the cost and time constraints that come with whole organ studies. This project created 3D scaffolds based on the trabecular portion of a sheep talus. Using these raw materials, pre-osteoblasts were injected onto the scaffold to test their proliferation within the 3D space. The purpose of this study was to create a three dimensional environment that was able to be coated and …