Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral,
2016
University of Dayton
Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral, Amit Singh, Kwang-Wook Choi
Amit Singh
Dorsoventral (DV) patterning is crucial for eye development in invertebrates and higher animals. DV lineage restriction is the primary event in undifferentiated early eye primordia of Drosophila. InDrosophila eye disc, a dorsal-specific GATA family transcription factor pannier (pnr) controls Iroquois-Complex (Iro-C) genes to establish the dorsal eye fate whereas Lobe (L), which is involved in controlling a Notch ligand Serrate (Ser), is specifically required for ventral growth. However, fate of eye disc cells before the onset of dorsal expression of pnr and Iro-C is not known. We show that L/Ser …
Cell Type-Specific Responses To Wingless, Hedgehog And Decapentaplegic Are Essential For Patterning Early Eye-Antenna Disc In Drosophila,
2016
Korea Advanced Institute of Science and Technology
Cell Type-Specific Responses To Wingless, Hedgehog And Decapentaplegic Are Essential For Patterning Early Eye-Antenna Disc In Drosophila, Jong-Hoon Won, Orkhon Tsogtbartarr, Wonseok Son, Amit Singh, Kwang-Wook Choi, Kyung-Ok Cho
Amit Singh
The Drosophila eye-antenna imaginal disc (ead) is a flattened sac of two-layered epithelia, from which most head structures are derived. Secreted morphogens like Wingless (Wg), Hedgehog (Hh), and Decapentaplegic (Dpp) are important for early patterning of ead, but the underlying mechanisms are still largely unknown. To understand how these morphogens function in the ead of early larval stages, we used wg-LacZ and dpp-Gal4 markers for the examination of wild-type and mutant eads. We found that the ead immediately after hatching was crescent-shaped with the Bolwig’s nerve at the ventral edge, suggesting that it consists of dorsal domain. In a subsequent …
Eye Development At The Houston "Fly Meeting",
2016
University of Dayton
Eye Development At The Houston "Fly Meeting", Amit Singh
Amit Singh
Meeting report: The 47th Annual Drosophila Research Conference or "Fly Meeting" took place at Houston, Texas, USA from March 29th- April 2nd, 2006, under the aegis of the Genetics Society of America. The Fly Meeting provides an excellent opportunity for fly researchers to present their work and to get a snapshot of recent developments and upcoming trends in their research field. The fruit fly, Drosophila melanogaster, is a very versatile model to study growth, patterning, neural development, evolution, systemetics and various other facets of biomedical science. The topics presented in the meeting covered a very broad spectrum of fly research. …
Eye Suppression, A Novel Function Of Teashirt, Requires Wingless Signaling,
2016
University of Dayton
Eye Suppression, A Novel Function Of Teashirt, Requires Wingless Signaling, Amit Singh, Madhuri Kango-Singh, Y. Henry Sun
Amit Singh
Teashirt (tsh) encodes a Drosophila zinc-finger protein. Misexpression of tsh has been shown to induce ectopic eye formation in the antenna. We report that tsh can suppress eye development. This novel function of tsh is due to the induction of homothorax (hth), a known repressor of eye development, and requires Wingless (WG) signaling. Interestingly, tsh has different functions in the dorsal and ventral eye, suppressing eye development close to the ventral margin, while promoting eye development near the dorsal margin. It affects both growth of eye disc and retinal cell differentiation.
Rapid Evolution Of Sex-Pheromone-Producing Enzyme In Drosophila,
2016
University of Wisconsin-Madison
Rapid Evolution Of Sex-Pheromone-Producing Enzyme In Drosophila, Troy R. Shirangi, Héloïse D. Dufour, Thomas M. Williams, Sean B. Carroll
Thomas M. Williams
A wide range of organisms use sex pheromones to communicate with each other and to identify appropriate mating partners. While the evolution of chemical communication has been suggested to cause sexual isolation and speciation, the mechanisms that govern evolutionary transitions in sex pheromone production are poorly understood. Here, we decipher the molecular mechanisms underlying the rapid evolution in the expression of a gene involved in sex pheromone production in Drosophilid flies. Long-chain cuticular hydrocarbons (e.g., dienes) are produced female-specifically, notably via the activity of the desaturase DESAT-F, and are potent pheromones for male courtship behavior in Drosophila melanogaster. We …
The Evolutionary Origination And Diversification Of A Dimorphic Gene Regulatory Network Through Parallel Innovations In Cis And Trans,
2016
University of Dayton
The Evolutionary Origination And Diversification Of A Dimorphic Gene Regulatory Network Through Parallel Innovations In Cis And Trans, Eric M. Camino, John C. Butts, Alison J. Ordway, Jordan E. Vellky, Mark Rebeiz, Thomas M. Williams
Thomas M. Williams
The origination and diversification of morphological characteristics represents a key problem in understanding the evolution of development. Morphological traits result from gene regulatory networks (GRNs) that form a web of transcription factors, which regulate multiple cis-regulatory element (CRE) sequences to control the coordinated expression of differentiation genes. The formation and modification of GRNs must ultimately be understood at the level of individual regulatory linkages (i.e., transcription factor binding sites within CREs) that constitute the network. Here, we investigate how elements within a network originated and diversified to generate a broad range of abdominal pigmentation phenotypes among Sophophora fruit flies. …
Quantitative Comparison Of Cis-Regulatory Element (Cre) Activities In Transgenic Drosophila Melanogaster,
2016
University of Dayton
Quantitative Comparison Of Cis-Regulatory Element (Cre) Activities In Transgenic Drosophila Melanogaster, William A. Rogers, Thomas M. Williams
Thomas M. Williams
Gene expression patterns are specified by cis-regulatory element (CRE) sequences, which are also called enhancers or cis-regulatory modules. A typical CRE possesses an arrangement of binding sites for several transcription factor proteins that confer a regulatory logic specifying when, where, and at what level the regulated gene(s) is expressed. The full set of CREs within an animal genome encodes the organism′s program for development1, and empirical as well as theoretical studies indicate that mutations in CREs played a prominent role in morphological evolution2-4. Moreover, human genome wide association studies indicate that genetic variation in CREs …
Recurrent Modification Of A Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity,
2016
University of Dayton
Recurrent Modification Of A Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity, William A. Rogers, Joseph R. Salomone, David J. Tacy, Eric M. Camino, Kristen A. Davis, Mark Rebeiz, Thomas M. Williams
Thomas M. Williams
The development of morphological traits occurs through the collective action of networks of genes connected at the level of gene expression. As any node in a network may be a target of evolutionary change, the recurrent targeting of the same node would indicate that the path of evolution is biased for the relevant trait and network. Although examples of parallel evolution have implicated recurrent modification of the same gene and cis-regulatory element (CRE), little is known about the mutational and molecular paths of parallel CRE evolution. InDrosophila melanogaster fruit flies, the Bric-à-brac (Bab) transcription factors control the development …
The Cytoplasmic Domain Of Membrane-Type 1 Matrix Metalloproteinase Is Required For Its Survival-Promoting, But Not Its Migration-Promoting Function In Mcf-7 Breast Cancer Cells,
2016
The University of Western Ontario
The Cytoplasmic Domain Of Membrane-Type 1 Matrix Metalloproteinase Is Required For Its Survival-Promoting, But Not Its Migration-Promoting Function In Mcf-7 Breast Cancer Cells, Jacob Jh Pelling
Electronic Thesis and Dissertation Repository
Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a multifunctional protease that degrades proteins during cell migration, and influences cell survival. Both the protein localization and signal transduction capabilities of MT1-MMP depend on its cytoplasmic domain (CD), indicative of a diverse regulatory function. The effects of CD mutations on cell migration and survival were examined by ectopically expressing MT1-MMP variants in MCF-7 cells. CD alteration by substitution or deletion did not abolish the migration-promoting effects of MT1-MMP, but did decrease cell survival and increase apoptosis. Expression of CD-altered MT1-MMP resulted in a protrusive cell morphology in 3D culture that was lost upon …
Loss Of Cell Adhesion Increases Tumorigenic Potential Of Polarity Deficient Scribble Mutant Cells,
2016
University of Dayton
Loss Of Cell Adhesion Increases Tumorigenic Potential Of Polarity Deficient Scribble Mutant Cells, Indrayani Waghmare, Madhuri Kango-Singh
Biology Faculty Publications
Epithelial polarity genes are important for maintaining tissue architecture, and regulating growth. The Drosophila neoplastic tumor suppressor gene scribble (scrib) belongs to the basolateral polarity complex. Loss of scrib results in disruption of its growth regulatory functions, and downregulation or mislocalization of Scrib is correlated to tumor growth. Somatic scribble mutant cells (scrib-) surrounded by wild-type cells undergo apoptosis, which can be prevented by introduction of secondary mutations that provide a growth advantage. Using genetic tools in Drosophila, we analyzed the phenotypic effects of loss of scrib in different growth promoting backgrounds. We investigated if a central …
Staphylococcus Aureus Coordinates Leukocidin Expression And Pathogenesis By Sensing Metabolic Fluxes Via Rpirc,
2016
New York University School of Medicine
Staphylococcus Aureus Coordinates Leukocidin Expression And Pathogenesis By Sensing Metabolic Fluxes Via Rpirc, Divya Balasubramanian, Elizabeth A Ohneck, Jessica Chapman, Andy Weiss, Min Kyung Kim, Tamara Reyes-Robles, Judy Zhong, Lindsey N. Shaw, Desmond S. Lun, Beatrix Ueberheide, Bo Shopsin, Victor J Torres
Molecular Biosciences Faculty Publications
Staphylococcus aureus is a formidable human pathogen that uses secreted cytolytic factors to injure immune cells and promote infection of its host. Of these proteins, the bicomponent family of pore-forming leukocidins play critical roles in S. aureus pathogenesis. The regulatory mechanisms governing the expression of these toxins are incompletely defined. In this work, we performed a screen to identify transcriptional regulators involved in leukocidin expression in S. aureus strain USA300. We discovered that a metabolic sensor-regulator, RpiRc, is a potent and selective repressor of two leukocidins, LukED and LukSF-PV. Whole-genome transcriptomics, S. aureus exoprotein proteomics, and metabolomic analyses revealed that …
Protein Trap Lines Of Drosophila To Demonstrate Spatio-Temporal Localization Of Proteins In An Undergraduate Lab,
2016
University of Dayton
Protein Trap Lines Of Drosophila To Demonstrate Spatio-Temporal Localization Of Proteins In An Undergraduate Lab, Oorvashi Roy Puli, Amit Singh
Amit Singh
The objective of this teaching note is to generate a laboratory exercise, which allows students to get a hands-on experience of a cell biology technique. The short duration of the laboratory classes is the biggest challenge with the development of a cell biology lab for an undergraduate curriculum. Therefore, it is necessary to design a laboratory exercise that enables the students to carry out cell biological assays in the desired time. This laboratory exercise focuses on tracking protein expression levels along a spatial (space) and temporal (time) axis in developing Drosophila melanogaster organ primordium. Here we use the protein trap …
A Cell Biology Laboratory Exercise To Study Sub-Cellular Organelles In Drosophila,
2016
University of Dayton
A Cell Biology Laboratory Exercise To Study Sub-Cellular Organelles In Drosophila, Meghana Tare, Amit Singh
Amit Singh
The fast-changing scenario of undergraduate education puts emphasis on introducing students to hands-on techniques as part of their laboratory courses. In order to cater to large numbers of students and the time constraints involved with undergraduate level laboratory courses, there is a need for development of experiments that are cost effective and can be completed in a defined time frame. We have devised a laboratory exercise for teaching cell biology using the Drosophila melanogaster model. Drosophila can be reared in a short period of time in a cost effective manner. We used Drosophila tissue to study the sub-cellular organization of …
Drosophila Adult Eye Model To Teach Scanning Electron Microscopy In An Undergraduate Cell Biology Laboratory,
2016
University of Dayton
Drosophila Adult Eye Model To Teach Scanning Electron Microscopy In An Undergraduate Cell Biology Laboratory, Meghana Tare, Oorvashi Roy Puli, Sarah M. Oros, Amit Singh
Amit Singh
We have devised an undergraduate laboratory exercise to study tissue morphology using fruit fly, Drosophila melanogaster, as the model organism. Drosophila can be reared in a cost effective manner in a short period of time. This experiment was a part of the undergraduate curriculum of the cell biology laboratory course aimed to demonstrate the use of scanning electron microscopy (SEM) technique to study the morphology of adult eye of Drosophila. The adult eye of Drosophila is a compound eye, which comprises of 800 unit eyes, and serves as an excellent model for SEM studies. We used flies that …
Dynamic Surfaces For The Study Of Mesenchymal Stem Cell Growth Through Adhesion Regulation,
2016
University of Glasgow
Dynamic Surfaces For The Study Of Mesenchymal Stem Cell Growth Through Adhesion Regulation, Jemma N. Roberts, Jugal Kishore Sahoo, Laura E. Mcnamara, Karl V. Burgess, Jingli Yang, Enateri V. Alakpa, Hilary J. Anderson, Jake Hay, Lesley-Anne Turner, Stephen J. Yarwood, Mischa Zelzer, Richard O.C. Oreffo, Rein V. Ulijn, Matthew J. Dalby
Advanced Science Research Center
Out of their niche environment, adult stem cells, such as mesenchymal stem cells (MSCs), spontaneously differentiate. This makes both studying these important regenerative cells and growing large numbers of stem cells for clinical use challenging. Traditional cell culture techniques have fallen short of meeting this challenge, but materials science offers hope. In this study, we have used emerging rules of managing adhesion/ cytoskeletal balance to prolong MSC cultures by fabricating controllable nanoscale cell interfaces using immobilized peptides that may be enzymatically activated to change their function. The surfaces can be altered (activated) at will to tip adhesion/cytoskeletal balance and initiate …
The Role Of Nadph Oxidase In Ros Mediated Differentiation,
2016
The University of Western Ontario
The Role Of Nadph Oxidase In Ros Mediated Differentiation, Benjamin J. Dickson
Electronic Thesis and Dissertation Repository
Mouse teratocarcinoma F9 cells differentiate into primitive endoderm (PrE) when treated with retinoic acid (RA) or H2O2 and these changes are accompanied by an upregulation of Wnt6 and activation of the canonical WNT/β-catenin pathway. Data from our lab shows PrE differentiation is accompanied by an increase in reactive oxygen species (ROS), which induces a conformational change in Nucleoredoxin preventing its ability to bind and inhibit Dishevelled. This in turn positively impacts on the WNT/β- catenin signaling pathway leading to differentiation. The source of endogenous ROS seen following RA treatment was investigated and members of the NADPH oxidase (NOX) family were …
Genetic Changes To A Transcriptional Silencer Element Confers Phenotypic Diversity Within And Between Drosophila Species,
2016
University of Pittsburgh
Genetic Changes To A Transcriptional Silencer Element Confers Phenotypic Diversity Within And Between Drosophila Species, Winslow C. Johnson, Alison J. Ordway, Masayoshi Watada, Jonathan N. Pruitt, Thomas M. Williams, Mark Rebeiz
Thomas M. Williams
The modification of transcriptional regulation has become increasingly appreciated as a major contributor to morphological evolution. However, the role of negative-acting control elements (e.g. silencers) in generating morphological diversity has been generally overlooked relative to positive-acting “enhancer” elements. The highly variable body coloration patterns among Drosophilid insects represents a powerful model system in which the molecular alterations that underlie phenotypic diversity can be defined. In a survey of pigment phenotypes among geographically disparate Japanese populations of Drosophila auraria, we discovered a remarkable degree of variation in male-specific abdominal coloration. In testing the expression patterns of the major pigment-producing enzymes, …
Nfat5/Stat3 Interaction Mediates Synergism Of High Salt With Il-17 Towards Induction Of Vegf-A Expression In Breast Cancer Cells,
2016
Mercy Hospital
Nfat5/Stat3 Interaction Mediates Synergism Of High Salt With Il-17 Towards Induction Of Vegf-A Expression In Breast Cancer Cells, Suneetha Amara, Dalal Alotaibi, Venkataswarup Tiriveedhi
Biology Faculty Research
Chronic inflammation has been considered an important player in cancer proliferation and progression. High salt (sodium chloride) levels have been considered a potent inducer of chronic inflammation. In the present study, the synergistic role of high salt with interleukin (IL)‑17 towards induction of the inflammatory and angiogenic stress factor vascular endothelial growth factor (VEGF)‑A was investigated. Stimulation of MCF-7 breast cancer cells with high salt (0.2 M NaCl) and sub‑minimal IL‑17 (1 ng/ml) enhanced the expression of VEGF-A (2.9 and 2.6-fold, respectively, P<0.05) compared with untreated cells. Furthermore, co‑treatment with both high salt and sub‑minimal IL‑17 led to a 5.9‑fold increase in VEGF‑A expression (P<0.01), thus suggesting a synergistic role of these factors. VEGF‑A promoter analysis and specific small interfering RNA knock‑down of transcription factors revealed that high salt induced VEGF‑A expression through nuclear factor of activated T‑cells (NFAT)5, while IL‑17 induced VEGF‑A expression via signal transducer and activator of transcription (STAT)3 signaling mechanisms. Treatment of normal human aortic endothelial cells with the supernatant of activated MCF‑7 cells enhanced cell migration and induced expression of migration‑specific factors, including vascular cell adhesion protein, β1 integrin and cluster of differentiation 31. These data suggest that high salt levels synergize with pro‑inflammatory IL‑17 to potentially induce cancer progression and metastasis through VEGF‑A expression. Therefore, low‑salt diet, anti‑NFAT5 and anti‑STAT3 therapies may provide novel avenues for enhanced efficiency of the current cancer therapy.
Intronic Cleavage And Polyadenylation Regulates Gene Expression During Dna Damage Response Through U1 Snrna,
2016
CUNY Kingsborough Community College
Intronic Cleavage And Polyadenylation Regulates Gene Expression During Dna Damage Response Through U1 Snrna, Emral Devany, Ji Yeon Park, Michael R. Murphy, George Zakusilo, Jorge Baquero, Xiaokan Zhang, Mainul Hoque, Bin Tian, Frida E. Kleiman
Publications and Research
The DNA damage response involves coordinated control of gene expression and DNA repair. Using deep sequencing, we found widespread changes of alternative cleavage and polyadenylation site usage on ultraviolet-treatment in mammalian cells. Alternative cleavage and polyadenylation regulation in the 3ʹ untranslated region is substantial, leading to both shortening and lengthening of 3ʹ untranslated regions of genes. Interestingly, a strong activation of intronic alternative cleavage and polyadenylation sites is detected, resulting in widespread expression of truncated transcripts. Intronic alternative cleavage and polyadenylation events are biased to the 5ʹ end of genes and affect gene groups with important functions in DNA damage …
Hexavalent Chromium Induces Malignant Transformation Of Human Lung Bronchial Epithelial Cells Via Ros-Dependent Activation Of Mir-21-Pdcd4 Signaling,
2016
University of Kentucky
Hexavalent Chromium Induces Malignant Transformation Of Human Lung Bronchial Epithelial Cells Via Ros-Dependent Activation Of Mir-21-Pdcd4 Signaling, Poyil Pratheeshkumar, Young-Ok Son, Sasidharan Padmaja Divya, Lilia Turcios, Ram Vinod Roy, John Andrew Hitron, Lei Wang, Donghern Kim, Jin Dai, Padmaja Asha, Zhuo Zhang, Xianglin Shi
Center for Research on Environmental Disease Faculty Publications
Hexavalent chromium [Cr(VI)] is a well-known human carcinogen associated with an increased risk of lung cancer. However, the mechanisms underlying Cr(VI)-induced carcinogenesis remain unclear. MicroRNA-21 (miR-21) is a key regulator of oncogenic processes. Studies have shown that miR-21 exerts its oncogenic activity by targeting the tumor suppressor gene programmed cell death 4 (PDCD4). The present study examined the role of miR-21-PDCD4 signaling in Cr(VI)-induced cell transformation and tumorigenesis. Results showed that Cr(VI) induces ROS generation in human bronchial epithelial (BEAS-2B) cells. Chronic exposure to Cr(VI) is able to cause malignant transformation in BEAS-2B cells. Cr(VI) caused a significant increase of …
