Medicine and Health Sciences Commons^™

Repressive Interactions Between Transcription Factors Separate Different Embryonic Ectodermal Domains., Steven L. Klein, Andre L P Tavares, Meredith Peterson, Charles H Sullivan, Sally A. Moody

Anatomy and Regenerative Biology Faculty Publications

The embryonic ectoderm is composed of four domains: neural plate, neural crest, pre-placodal region (PPR) and epidermis. Their formation is initiated during early gastrulation by dorsal-ventral and anterior-posterior gradients of signaling factors that first divide the embryonic ectoderm into neural and non-neural domains. Next, the neural crest and PPR domains arise, either

Differentiation Of Fetal Hematopoietic Stem Cells Requires Arid4b To Restrict Autocrine Kitlg/Kit-Src Signaling., In-Chi Young, Bogang Wu, Jaclyn Andricovich, Sung-Ting Chuang, Rong Li, Alexandros Tzatsos, Ray-Chang Wu, Mei-Yi Wu

Anatomy and Regenerative Biology Faculty Publications

No abstract provided.

Corneal Nonmyelinating Schwann Cells Illuminated By Single-Cell Transcriptomics And Visualized By Protein Biomarkers., Paola Bargagna-Mohan, Gwendolyn Schultz, Bruce Rheaume, Ephraim F Trakhtenberg, Paul Robson, Sonali Pal-Ghosh, Mary Ann Stepp, Katherine S Given, Wendy B Macklin, Royce Mohan

Anatomy and Regenerative Biology Faculty Publications

No abstract provided.

Emerging Cellular And Molecular Strategies For Enhancing Central Nervous System (Cns) Remyelination., Mohammad Abu-Rub, Robert H Miller

Anatomy and Regenerative Biology Faculty Publications

Myelination is critical for the normal functioning of the central nervous system (CNS) in vertebrates. Conditions in which the development of myelin is perturbed result in severely compromised individuals often with shorter lifespans, while loss of myelin in the adult results in a variety of functional deficits. Although some form of spontaneous remyelination often takes place, the repair process as a whole often fails. Several lines of evidence suggest it is feasible to develop strategies that enhance the capacity of the CNS to undergo remyelination and potentially reverse functional deficits. Such strategies include cellular therapies using either neural or mesenchymal …

Reduced Intraepithelial Corneal Nerve Density And Sensitivity Accompany Desiccating Stress And Aging In C57bl/6 Mice, Mary Ann Stepp, Sonali Pal-Ghosh, Gauri Tadvalkar, Alexa Williams, S Pflugfelder, C De Paiva

Anatomy and Regenerative Biology Faculty Publications

Dry Eye disease causes discomfort and pain in millions of patients. Using a mouse acute desiccating stress (DS) model we show that DS induces a reduction in intraepithelial corneal nerve (ICN) density, corneal sensitivity, and apical extension of the intraepithelial nerve terminals (INTs) that branch from the subbasal nerves (SBNs). Topical application of 0.02% Mitomycin C (MMC) or vehicle alone has no impact on the overall loss of axon density due to acute DS. Chronic dry eye, which develops progressively as C57BL/6 mice age, is accompanied by significant loss of the ICNs and corneal sensitivity between 2 and 24 months …

Epigenetic Modifiers Promote Mitochondrial Biogenesis And Oxidative Metabolism Leading To Enhanced Differentiation Of Neuroprogenitor Cells., Martine Uittenbogaard, Christine A Brantner, Anne Chiaramello

Anatomy and Regenerative Biology Faculty Publications

During neural development, epigenetic modulation of chromatin acetylation is part of a dynamic, sequential and critical process to steer the fate of multipotent neural progenitors toward a specific lineage. Pan-HDAC inhibitors (HDCis) trigger neuronal differentiation by generating an "acetylation" signature and promoting the expression of neurogenic bHLH transcription factors. Our studies and others have revealed a link between neuronal differentiation and increase of mitochondrial mass. However, the neuronal regulation of mitochondrial biogenesis has remained largely unexplored. Here, we show that the HDACi, sodium butyrate (NaBt), promotes mitochondrial biogenesis via the NRF-1/Tfam axis in embryonic hippocampal progenitor cells and neuroprogenitor-like PC12-NeuroD6 …

Epha2/Ephrin-A1 Mediate Corneal Epithelial Cell Compartmentalization Via Adam10 Regulation Of Egfr Signaling., Nihal Kaplan, Rosa Ventrella, Han Peng, Sonali Pal-Ghosh, Constadina Arvanitis, Joshua Z Rappoport, Brian J Mitchell, Mary Ann Stepp, Robert M Lavker, Spiro Getsios

Anatomy and Regenerative Biology Faculty Publications

Purpose: Progenitor cells of the limbal epithelium reside in a discrete area peripheral to the more differentiated corneal epithelium and maintain tissue homeostasis. What regulates the limbal-corneal epithelial boundary is a major unanswered question. Ephrin-A1 ligand is enriched in the limbal epithelium, whereas EphA2 receptor is concentrated in the corneal epithelium. This reciprocal pattern led us to assess the role of ephrin-A1 and EphA2 in limbal-corneal epithelial boundary organization.

Methods: EphA2-expressing corneal epithelial cells engineered to express ephrin-A1 were used to study boundary formation in vitro in a manner that mimicked the relative abundance of these juxtamembrane signaling proteins in …

Increased Expression Of The Tight Junction Protein Tjp1/Zo-1 Is Associated With Upregulation Of Taz-Tead Activity And An Adult Tissue Stem Cell Signature In Carfilzomib-Resistant Multiple Myeloma Cells And High-Risk Multiple Myeloma Patients, Irene Riz, Robert G. Hawley

Anatomy and Regenerative Biology Faculty Publications

Tight junction protein 1 (TJP1) has recently been proposed as a biomarker to identify multiple myeloma (MM) patients most likely to respond to bortezomiband carfilzomib-based proteasome inhibitor regimens. Herein we report increased expression of TJP1 during the adaptive response mediating carfilzomib resistance in the LP-1/Cfz MM cell line. Moreover, increased TJP1 expression delineated a subset of relapsed/refractory MM patients on bortezomib-based therapy sharing an LP-1/Cfzlike phenotype characterized by activation of interacting transcriptional effectors of the Hippo signaling cascade (TAZ and TEAD1) and an adult tissue stem cell signature. siRNA-mediated knockdown of TJP1 or TAZ/TEAD1 partially sensitized LP-1/Cfz cells to carfilzomib. …

Mll3/Mll4 Are Required For Cbp/P300 Binding On Enhancers And Super-Enhancer Formation In Brown Adipogenesis., Binbin Lai, Ji-Eun Lee, Younghoon Jang, Lifeng Wang, Weiqun Peng, Kai Ge

Anatomy and Regenerative Biology Faculty Publications

Histone H3K4me1/2 methyltransferases MLL3/MLL4 and H3K27 acetyltransferases CBP/p300 are major enhancer epigenomic writers. To understand how these epigenomic writers orchestrate enhancer landscapes in cell differentiation, we have profiled genomic binding of MLL4, CBP, lineage-determining transcription factors (EBF2, C/EBPβ, C/EBPα, PPARγ), coactivator MED1, RNA polymerase II, as well as epigenome (H3K4me1/2/3, H3K9me2, H3K27me3, H3K36me3, H3K27ac), transcriptome and chromatin opening during adipogenesis of immortalized preadipocytes derived from mouse brown adipose tissue (BAT). We show that MLL4 and CBP drive the dynamic enhancer epigenome, which correlates with the dynamic transcriptome. MLL3/MLL4 are required for CBP/p300 binding on enhancers activated during adipogenesis. Further, MLL4 …

Dbvar Structural Variant Cluster Set For Data Analysis And Variant Comparison, Ben Busby, Lon Phan, Jeffrey Hsu, Le Quang Minh Tri, Micheala Willi, Tamer A. Mansour, Yan Kai, John R. Garner, John R. Lopez

Anatomy and Regenerative Biology Faculty Publications

dbVar houses over 3 million submitted structural variants (SSV) from 120 human studies including copy number variations (CNV), insertions, deletions, inversions, translocations, and complex chromosomal rearrangements. Users can submit multiple SSVs to dbVAR that are presumably identical, but were ascertained by different platforms and samples, to calculate whether the variant is rare or common in the population and allow for cross validation. However, because SSV genomic location reporting can vary – including fuzzy locations where the start and/or end points are not precisely known – analysis, comparison, annotation, and reporting of SSVs across studies can be difficult. This project was …

Brd4 Binds To Active Enhancers To Control Cell Identity Gene Induction In Adipogenesis And Myogenesis, Ji-Eun Lee, Young-Kwon Park, Sarah Park, Younghoon Jang, Nicholas Waring, Anup Dey, Keiko Ozato, Binbin Lai, Weiqun Peng, Kai Ge

Anatomy and Regenerative Biology Faculty Publications

The epigenomic reader Brd4 is an important drug target for cancers. However, its role in cell differentiation and animal development remains largely unclear. Using two conditional knockout mouse strains and derived cells, we demonstrate that Brd4 controls cell identity gene induction and is essential for adipogenesis and myogenesis. Brd4 co-localizes with lineage-determining transcription factors (LDTFs) on active enhancers during differentiation. LDTFs coordinate with H3K4 mono-methyltransferases MLL3/MLL4 (KMT2C/KMT2D) and H3K27 acetyltransferases CBP/p300 to recruit Brd4 to enhancers activated during differentiation. Brd4 deletion prevents the enrichment of Mediator and RNA polymerase II transcription machinery, but not that of LDTFs, MLL3/MLL4-mediated H3K4me1, and …

Noncanonical Sqstm1/P62-Nrf2 Pathway Activation Mediates Proteasome Inhibitor Resistance In Multiple Myeloma Cells Via Redox, Metabolic And Translational Reprogramming., Irene Riz, Teresa S Hawley, Jeffrey W Marsal, Robert G Hawley

Anatomy and Regenerative Biology Faculty Publications

Multiple Myeloma (MM) is a B-cell malignancy characterized by the accumulation of clonal plasma cells in the bone marrow, with drug resistance being a major cause of therapeutic failure. We established a carfilzomib-resistant derivative of the LP-1 MM cell line (LP-1/Cfz) and found that the transcription factor NF-E2 p45-related factor 2 (Nrf2; gene symbol NFE2L2) contributes to carfilzomib resistance. The mechanism of Nrf2 activation involved enhanced translation of Nrf2 as well as its positive regulator, the autophagy receptor sequestosome 1 (SQSTM1)/p62. The eukaryotic translation initiation factor gene EIF4E3 was among the Nrf2 target genes upregulated in LP-1/Cfz cells, suggesting existence …

High-Sensitivity Mass Spectrometry For Probing Gene Translation In Single Embryonic Cells In The Early Frog (Xenopus) Embryo, Camille Lombard-Banek, Sally Ann Moody, Peter Nemes

Anatomy and Regenerative Biology Faculty Publications

Direct measurement of protein expression with single-cell resolution promises to deepen the understanding of basic molecular processes during normal and impaired development. High-resolution mass spectrometry provides detailed coverage of the proteomic composition of large numbers of cells. Here we discuss recent mass spectrometry developments based on single-cell capillary electrophoresis that extend discovery proteomics to sufficient sensitivity to enable the measurement of proteins in single cells. The single-cell mass spectrometry system is used to detect a large number of proteins in single embryonic cells in blastomeres in the 16-cell embryo of the South African clawed frog (Xenopus laevis) that give rise …

Inflammatory Bowel Disease, Colorectal Cancer And Type 2 Diabetes Mellitus: The Links., Abdo Jurjus, Assad Eid, Sahar Al Kattar, Marie Noel Zeenny, Alice Gerges-Geagea, Rosalyn A. Jurjus, +10 Additional Authors

Anatomy and Regenerative Biology Faculty Publications

The co-occurrence of the three disease entities, inflammatory bowel disease (IBD), colorectal cancer (CRC), type 2diabetes mellitus (T2DM) along with inflammation and dismicrobism has been frequently reported. Some authors have even suggested that dysbiosis could be the link through a molecular crosstalk of multiple inflammatory loops including TGFβ, NFKB, TNFα and ROS among others. This review focuses on the inflammatory process along with the role of microbiota in the pathophysiology of the three diseases. The etiology of IBD is multifactorial, and like CRC and T2DM, it is associated with a widespread and sustained GI inflammation and dismicrobism, whereby an array …

Oligodendrocyte Ablation As A Tool To Study Demyelinating Diseases, Ahdeah Pajoohesh-Ganji, Robert H. Miller

Anatomy and Regenerative Biology Faculty Publications

Multiple sclerosis (MS) is an autoimmune mediated neurodegenerative disease characterized by demyelination and oligodendrocyte (OL) loss in the central nervous system and accompanied by local inflammation and infiltration of peripheral immune cells. Although many risk factors and symptoms have been identified in MS, the pathology is complicated and the cause remains unknown. It is also unclear whether OL apoptosis precedes the inflammation or whether the local inflammation is the cause of OL death and demyelination. This review briefly discusses several models that have been developed to specifically ablate oligodendrocytes in an effort to separate the effects of demyelination from inflammation.

Localized Jnk Signaling Regulates Organ Size During Development., Helen Rankin Willsey, Xiaoyan Zheng, José Carlos Pastor-Pareja, A Jeremy Willsey, Philip A Beachy, Tian Xu

Anatomy and Regenerative Biology Faculty Publications

A fundamental question of biology is what determines organ size. Despite demonstrations that factors within organs determine their sizes, intrinsic size control mechanisms remain elusive. Here we show that Drosophila wing size is regulated by JNK signaling during development. JNK is active in a stripe along the center of developing wings, and modulating JNK signaling within this stripe changes organ size. This JNK stripe influences proliferation in a non-canonical, Jun-independent manner by inhibiting the Hippo pathway. Localized JNK activity is established by Hedgehog signaling, where Ci elevates dTRAF1 expression. As the dTRAF1 homolog, TRAF4, is amplified in numerous cancers, these …

K14+ Compound Niches Are Present On The Mouse Cornea Early After Birth And Expand After Debridement Wounds., Ahdeah Pajoohesh-Ganji, Sonali Pal-Ghosh, Gauri Tadvalkar, Mary Ann Stepp

Anatomy and Regenerative Biology Faculty Publications

Background: We previously identified compound niches (CNs) at the limbal:corneal border of the mouse cornea that contain corneal epithelial progenitor cells, express Keratin 8 (K8), and goblet cell mucin Muc5AC. During re-epithelialization after 2.5 mm epithelial debridement wounds, CNs migrate onto the cornea and expand in number mimicking conjunctivalization. When CNs form during development and whether they express corneal epithelial progenitor cell enriched K14 was not known.

Results: To provide insight into corneal epithelial homeostasis, we quantify changes in expression of simple (K8, K18, K19) and stratified squamous epithelial keratins (K5, K12, K14, and K15) during postnatal development and in …

Single-Cell Mass Spectrometry For Discovery Proteomics: Quantifying Translational Cell Heterogeneity In The 16-Cell Frog (Xenopus) Embryo, Camille Lombard-Banek, Sally Ann Moody, Peter Nemes

Anatomy and Regenerative Biology Faculty Publications

We advance mass spectrometry from a cell population-averaging tool to one capable of quantifying the expression of diverse proteins in single embryonic cells. Our instrument combines capillary electrophoresis (CE), electrospray ionization, and a tribrid ultrahigh-resolution mass spectrometer (HRMS) to enable untargeted (discovery) proteomics with ca. 25 amol lower limit of detection. CE-μESI-HRMS enabled the identification of 500–800 nonredundant protein groups by measuring 20 ng, or <0.2% of the total protein content in single blastomeres that were isolated from the 16-cell frog (Xenopus laevis) embryo, amounting to a total of 1709 protein groups identified between n=3 biological replicates. By quantifying ≈150 nonredundant protein groups between all blastomeres and replicate measurements, we found significant translational cell heterogeneity along multiple axes of the embryo at this very early stage of development when the transcriptional program of the embryo has yet to begin.

Weak Tradeoff Between Xylem Safety And Xylem-Specific Hydraulic Efficiency Across The World's Woody Plant Species., Sean M Gleason, Mark Westoby, Steven Jansen, Brendan Choat, Uwe G Hacke, Robert B Pratt, Radika Bhaskar, Tim J Brodribb, Sandra J Bucci, Kun-Fang Cao, Hervé Cochard, Sylvain Delzon, Jean-Christophe Domec, Ze-Xin Fan, Taylor S Feild, Anna L Jacobsen, Daniel M Johnson, Frederic Lens, Hafiz Maherali, Jordi Martínez-Vilalta, Stefan Mayr, Katherine A Mcculloh, Maurizio Mencuccini, Patrick J Mitchell, Hugh Morris, Andrea Nardini, Jarmila Pittermann, Lenka Plavcová, Stefan G Schreiber, John S Sperry, Ian J Wright, Amy E Zanne

Anatomy and Regenerative Biology Faculty Publications

The evolution of lignified xylem allowed for the efficient transport of water under tension, but also exposed the vascular network to the risk of gas emboli and the spread of gas between xylem conduits, thus impeding sap transport to the leaves. A well-known hypothesis proposes that the safety of xylem (its ability to resist embolism formation and spread) should trade off against xylem efficiency (its capacity to transport water). We tested this safety-efficiency hypothesis in branch xylem across 335 angiosperm and 89 gymnosperm species. Safety was considered at three levels: the xylem water potentials where 12%, 50% and 88% of …

Targeting Il13ralpha2 Activates Stat6-Tp63 Pathway To Suppress Breast Cancer Lung Metastasis, Panagiotis Papageorgis, Sait Ozturk, Arthur W. Lambert, Christiana M. Neophytou, Alexandros Tzatsos, Chen K. Wong, Sam Thiagalingam, Andreas I. Constantinou

Anatomy and Regenerative Biology Faculty Publications

Introduction

Basal-like breast cancer (BLBC) is an aggressive subtype often characterized by distant metastasis, poor patient prognosis, and limited treatment options. Therefore, the discovery of alternative targets to restrain its metastatic potential is urgently needed. In this study, we aimed to identify novel genes that drive metastasis of BLBC and to elucidate the underlying mechanisms of action.

Methods

An unbiased approach using gene expression profiling of a BLBC progression model and in silicoleveraging of pre-existing tumor transcriptomes were used to uncover metastasis-promoting genes. Lentiviral-mediated knockdown of interleukin-13 receptor alpha 2 (IL13Ralpha2) coupled with whole-body in vivo bioluminescence imaging was …

Klf4-Sqstm1/P62-Associated Prosurvival Autophagy Contributes To Carfilzomib Resistance In Multiple Myeloma Models., Irene Riz, Teresa S. Hawley, Robert G. Hawley

Anatomy and Regenerative Biology Faculty Publications

Multiple myeloma (MM) is an incurable clonal plasma cell malignancy. Because of a high rate of immunoglobulin synthesis, the endoplasmic reticulum of MM cells is subjected to elevated basal levels of stress. Consequently, proteasome inhibitors, which exacerbate this stress by inhibiting ubiquitin-proteasome-mediated protein degradation, are an important new class of chemotherapeutic agents being used to combat this disease. However, MM cells still develop resistance to proteasome inhibitors such as carfilzomib. Toward this end, we have established carfilzomib-resistant derivatives of MM cell lines. We found that resistance to carfilzomib was associated with elevated levels of prosurvival autophagy, and Kruppel-like factor 4 …

Medical Students In Microscopic Anatomy And Pathology Laboratories: Design Of An E-Learning Histology And Histopathology Atlas As An Evolving Response To Interdisciplinary Pre-Clinical Curricular Needs, Michelle S. Davis, Alexandra Mills, Gisela Butera, Donald S. Karcher, Patricia S. Latham, Janette Krum, Rosalyn A. Jurjus

Anatomy and Regenerative Biology Faculty Publications

E-learning, also known as computer-assisted learning, successfully bridges anatomical knowledge and transferrable skills, such as critical analysis, teamwork, leadership and communication. Several institutions have already integrated histology and physiology in team based laboratory approaches, but integration of histology and pathology instruction has been done to a lesser extent. Our aim was to develop an e-learning atlas that integrates microanatomy and pathology laboratory for an interdisciplinary pre-clinical medical curriculum.

A multidisciplinary team of teaching faculty and students developed an online atlas (microanatomyatlas.com) that includes a library of histology and histopathology images. Traditional laboratory manual instructions and study objectives were added onto …

Pharmaceutical Integrated Stress Response Enhancement Protects Oligodendrocytes And Provides A Potential Multiple Sclerosis Therapeutic., Sharon W Way, Joseph R Podojil, Benjamin L Clayton, Anita Zaremba, Tassie L Collins, Rejani B Kunjamma, Andrew P Robinson, Pedro Brugarolas, Robert H. Miller, Stephen D Miller, Brian Popko

Anatomy and Regenerative Biology Faculty Publications

Oligodendrocyte death contributes to the pathogenesis of the inflammatory demyelinating disease multiple sclerosis (MS). Nevertheless, current MS therapies are mainly immunomodulatory and have demonstrated limited ability to inhibit MS progression. Protection of oligodendrocytes is therefore a desirable strategy for alleviating disease. Here we demonstrate that enhancement of the integrated stress response using the FDA-approved drug guanabenz increases oligodendrocyte survival in culture and prevents hypomyelination in cerebellar explants in the presence of interferon-γ, a pro-inflammatory cytokine implicated in MS pathogenesis. In vivo, guanabenz treatment protects against oligodendrocyte loss caused by CNS-specific expression of interferon-γ. In a mouse model of MS, experimental …

The Use Of Stem Cells In Burn Wound Healing: A Review, Fadi Ghieh, Rosalyn A. Jurjus, Amir Ibrahim, Alice Gerges Geagea, Hisham Daouk, Bassel El Baba, Sana Cham, Michel Matar, Wadih Zein, Abdo Jurjus

Anatomy and Regenerative Biology Faculty Publications

Burn wound healing involves a series of complex processes which are subject to intensive investigations to improve the outcomes, in particular, the healing time and the quality of the scar. Burn injuries, especially severe ones, are proving to have devastating effects on the affected patients. Stem cells have been recently applied in the field to promote superior healing of the wounds. Not only have stem cells been shown to promote better and faster healing of the burn wounds, but also they have decreased the inflammation levels with less scar progression and fibrosis. This review aims to highlight the beneficial therapeutic …

Once Upon A Microscopic Slide: The Story Of Histology, Inaya Hussein, Mohamad Raad, Rawan Safa, Rosalyn A. Jurjus, Abdo Jurjus

Anatomy and Regenerative Biology Faculty Publications

For centuries, histology has maintained its remarkable place in the medical curriculum. However, its teaching has been influenced by the new technological advancement that has reshaped medicine teaching into a more modern student-friendly form. Since its inception in the 18th century, the discipline of histology has progressed hand in hand with the advancements in microscopy and microscopic technologies, including immunohistochemistry. In the traditional curriculum of USA medical schools, especially after the first Flexner’s report of 1910, histology was considered as very essential topic for a physician studying the “Art and Science” of medicine. In this era, the teaching relied more …

Atrial Fibrillation: Biophysics, Molecular Mechanisms, And Novel Therapies., Alexey V. Glukhov, Leonid V. Rosenshtraukh, Anamika Bhargava, Michele Miragoli, Bas J. D. Boukens

Anatomy and Regenerative Biology Faculty Publications

No abstract provided.

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 …

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 …

Simultaneous Measurement Of Smoothened Entry Into And Exit From The Primary Cilium, Jynho Kim, Elaine Y.C. Hsia, James Kim, Navdar Sever, Philip A. Beachy, Xiaoyan Zheng

Anatomy and Regenerative Biology Faculty Publications

Ciliary accumulation of signaling proteins must result from a rate of ciliary entry that exceeds ciliary exit, but approaches for distinguishing ciliary entry vs. exit are lacking. Using a photoconvertible fluorescent protein tag, we establish an assay that allows a separate but simultaneous examination of ciliary entry and exit of the Hedgehog signaling protein Smoothened in individual cells. We show that KAAD-cyclopamine selectively blocks entry, whereas ciliobrevin interferes initially with exit and eventually with both entry and exit of ciliary Smoothened. Our study provides an approach to understanding regulation of ciliary entry vs. exit of Hedgehog signaling components as well …

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 …