Life Sciences Commons^™

Modulation Of Tyramine Signaling By Osmolality In An Insect Secretory Epithelium, Edward M. Blumenthal

Biological Sciences Faculty Research and Publications

The control of water balance in multicellular organisms depends on absorptive and secretory processes across epithelia. This study concerns the effects of osmolality on the function of the Malpighian tubules (MTs), a major component of the insect excretory system. Previous work has shown that the biogenic amine tyramine increases transepithelial chloride conductance and urine secretion in Drosophila MTs. This study demonstrates that the response of MTs to tyramine, as measured by the depolarization of the transepithelial potential (TEP), is modulated by the osmolality of the surrounding medium. An increase in osmolality caused decreased tyramine sensitivity, whereas a decrease in osmolality …

Mesodermally Expressed Drosophila Microrna-1 Is Regulated By Twist And Is Required In Muscles During Larval Growth., Nicholas S. Sokol, Victor R. Ambros

Victor R. Ambros

Although hundreds of evolutionarily conserved microRNAs have been discovered, the functions of most remain unknown. Here, we describe the embryonic spatiotemporal expression profile, transcriptional regulation, and loss-of-function phenotype of Drosophila miR-1 (DmiR-1). DmiR-1 RNA is highly expressed throughout the mesoderm of early embryos and subsequently in somatic, visceral, and pharyngeal muscles, and the dorsal vessel. The expression of DmiR-1 is controlled by the Twist and Mef2 transcription factors. DmiR-1KO mutants, generated using ends-in gene targeting, die as small, immobilized second instar larvae with severely deformed musculature. This lethality is rescued when a DmiR-1 transgene is expressed specifically in the mesoderm …

Monitoring Activity Of Drosophila Larvae: Impedance & Video Microscopy Measures, Ann Simone Cooper, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Monitoring Heart Rate In Drosophila Larvae By Various Approaches, Sameera Dasari, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Monitoring Carbon Dioxide Production By Drosophila Larvae, Robin L. Cooper, D. Nicholas Mcletchie

Biology Faculty Publications

No abstract provided.

The N-Terminal Prodomain Of Sv23 Is Essential For The Assembly Of A Functional Vitelline Membrane Network In Drosophila, Anita L. Manogaran, Gail L. Waring

Biological Sciences Faculty Research and Publications

The vitelline membrane is a specialized extracellular matrix that surrounds and protects the oocyte. Recent studies indicate that it also serves as a storage site for embryonic pattern determinants. sV23, a major vitelline membrane protein, is essential for the morphogenesis of the vitelline membrane as sV23 protein null mutants lay flaccid, infertile eggs. By analyzing a series of sV23 mutant transgenes in the sV23 protein null genetic background, we have shown that sV23 is secreted as a proprotein in functional excess and that C- and N-terminal prodomains are removed successively, following its deposition in the extracellular space. Although a target …

A Regulatory Code For Neurogenic Gene Expression In The Drosophila Embryo, Michele Markstein, Robert Zinzen, Peter Markstein, Ka Ping Yee, Albert Erives, Angela Stathopoulos, Michael Levine

Michele Markstein

Bioinformatics methods have identified enhancers that mediate restricted expression in the Drosophila embryo. However, only a small fraction of the predicted enhancers actually work when tested in vivo. In the present study, co-regulated neurogenic enhancers that are activated by intermediate levels of the Dorsal regulatory gradient are shown to contain several shared sequence motifs. These motifs permitted the identification of new neurogenic enhancers with high precision: five out of seven predicted enhancers direct restricted expression within ventral regions of the neurogenic ectoderm. Mutations in some of the shared motifs disrupt enhancer function, and evidence is presented that the Twist and …

Drawing Lines In The Sand: Even Skipped Et Al. And Parasegment Boundaries., James B. Jaynes, Miki Fujioka

Department of Biochemistry and Molecular Biology Faculty Papers

The pair-rule segmentation gene even skipped (eve) is required to activate engrailed stripes and to organize odd-numbered parasegments (PSs). The protein product Eve has been shown to be an active repressor of transcription, and recent models for Eve function suggest that activation of engrailed is indirect, but these models have not been fully tested. Here we identify the forkhead domain transcription factor Sloppy-paired as the key intermediate in the initial activation of engrailed by Eve in odd-numbered parasegments. We also analyze the roles of the transcription factors Runt and Odd-skipped in this process. Detailed analysis of engrailed and pair-rule gene …

The Cohesion Protein Ord Is Required For Homologue Bias During Meiotic Recombination, Hayley A. Webber, Louisa Howard, Sharon E. Bickel

Dartmouth Scholarship

During meiosis, sister chromatid cohesion is required for normal levels of homologous recombination, although how cohesion regulates exchange is not understood. Null mutations in orientation disruptor (ord) ablate arm and centromeric cohesion during Drosophila meiosis and severely reduce homologous crossovers in mutant oocytes. We show that ORD protein localizes along oocyte chromosomes during the stages in which recombination occurs. Although synaptonemal complex (SC) components initially associate with synapsed homologues in ord mutants, their localization is severely disrupted during pachytene progression, and normal tripartite SC is not visible by electron microscopy. In ord germaria, meiotic double strand breaks appear …

Fc177, A Minor Dec-1 Proprotein, Is Necessary To Prevent Ectopic Aggregation Of The Endochorion During Eggshell Assembly In Drosophila, Debra Kay Mauzy-Melitz, Gail L. Waring

Biological Sciences Faculty Research and Publications

The Drosophila eggshell is a highly specialized extracellular matrix that forms between the oocyte and the surrounding epithelial follicle cells during late oogenesis. The dec-1 gene, which is required for proper eggshell assembly, produces three proproteins that are cleaved within the vitelline membrane layer to multiple derivatives. The different spatial distributions of the cleaved derivatives suggest that they play distinct roles in eggshell assembly. Using extant dec-1 mutations in conjunction with genetically engineered dec-1 transgenes, we show that, although all three dec-1 proproteins, fc106, fc125, and fc177, are required for female fertility, gross morphological abnormalities in the eggshell are observed …

Anti-Genotoxic Effect Of Ascorbic Acid On Mutagenic Dose Of Three Alkylating Agents, Bülent Kaya

Turkish Journal of Biology

The antimutagenic effect of ascorbic acid (vitamin C) was investigated by using the Drosophila wing spot test. In this assay, 3-day-old transheterozygous larvae for the multiple wing hair (mwh, 3-0.3) and flare (flr, 3-38.8) genes were treated with 3 direct acting mutagens: ethyl methanesulfonate (EMS), methyl methanesulfonate (MMS) and N-nitroso N-ethylurea (ENU). The results obtained from 3 reference mutagens were clearly genotoxic in the Drosophila wing somatic mutation and recombination test. The calculated concentration of ascorbic acid as recommended dietary allowance (RDA) did not induce the frequency of the mutant clones recorded. When co-treatment experiments with ascorbic acid were carried …

The Physiology Of Life History Trade-Offs In Animals, Anthony J. Zera, Lawrence G. Harshman

Anthony Zera Publications

The functional causes of life history trade-offs have been a topic of interest to evolutionary biologists for over six decades. Our review of life history trade-offs discusses conceptual issues associated with physiological aspects of trade-offs, and it describes recent advances on this topic. We focus on studies of four model systems: wing polymorphic insects, Drosophila, lizards, and birds. The most significant recent advances have been: (a) incorporation of genetics in physiological studies of trade-offs, (b) integration of investigations of nutrient input with nutrient allocation, (c) development of more sophisticated models of resource acquisition and allocation, (d) a shift to more …

Life-History Evolution In Guppies. Vii. The Comparative Ecology Of High- And Low-Predation Environments, David Reznick, Mark J. Butler Iv, Helen Rodd

Biological Sciences Faculty Publications

Prior research has demonstrated a strong association between the species of predators that co-occur with guppies and the evolution of guppy life histories. The evolution of these differences in life histories has been attributed to the higher mortality rates experienced by guppies in high-predation environments. Here, we evaluate whether there might be indirect effects of predation on the evolution of life-history patterns and whether there are environmental differences that are correlated with predation. To do so, we quantified features of the physical and chemical environment and the population biology of guppies from seven high-and low-predation localities. We found that high-predation …

Lack Of Minority Advantage In Drosophilamelanogaster Mutants, Şükran Çakir, Aykut Kence

Turkish Journal of Biology

The objective of this study was to test the generality of frequency-dependent fitness in the mating behavior of Drosophila, called the minority effect and to investigate the effect of artificial olfactory cues and marking the flies by wing cillipng on the frequency-dependent mate choice. In the mating experiments using wild type (oregon) and mutant (white-eyed, sepia, ebony) strains of Drosophila melanogaster, the mating success of mutant males did not increase as their frequency decreased. In addition, the olfactory cue hypothesis was not supported by the results of the experiments with artificial scent. The results of this study did not support …

Drosophila Unpaired Encodes A Secreted Protein That Activates The Jak Signaling Pathway, Douglas A. Harrison, Patricia E. Mccoon, Richard Binari, Michael Gilman, Norbert Perrimon

Biology Faculty Publications

In vertebrates, many cytokines and growth factors have been identified as activators of the JAK/STAT signaling pathway. In Drosophila, JAK and STAT molecules have been isolated, but no ligands or receptors capable of activating the pathway have been described. We have characterized the unpaired (upd) gene, which displays the same distinctive embryonic mutant defects as mutations in the Drosophila JAK (hopscotch) and STAT (stat92E) genes. Upd is a secreted protein, associated with the extracellular matrix, that activates the JAK pathway. We propose that Upd is a ligand that relies on JAK signaling to stimulate transcription of pair-rule genes in a …

Crossroads, Milestones, Amd Landmarks In Insect Development And Evolution: Implications For Systematics, Rob Desalle, Donat Agosti, Michael Whiting, Beatriz Perez-Sweeney, James Remsen, Rick Baker, James Bonacum, Ranhy Bang

Aliso: A Journal of Systematic and Floristic Botany

Our understanding of insect development and evolution has increased greatly due to recent advances in the comparative developmental approach. Modem developmental biology techniques such as in situ hybridization and molecular analysis of developmentally important genes and gene families have greatly facilitated these advances. The role of the comparative developmental approach in insect systematics is explored in this paper and we suggest two important applications of the approach to insect systematics--character dissection and morphologicallandmarking. Exi~ng morphological characters can be dissected into their genetic and molecular components in some cases and this will lead to more and richer character information in systematic …

Cloning A Putative Dna-Binding Protein Controlling The 5'Ltr Of The Copia Element In Drosophila, Horng-Yuan Kan

Theses and Dissertations in Biomedical Sciences

Copia, a Drosophila retrotransposon, is constitutively expressed in all developmental stages, except the embryo in Drosophila melanogaster. The effect of random integration of the copia element results in phenotypic change in Drosophila. The regulatory sequences, controlling copia expression, are located within the 5'LTR. The DNA sequence in the 5'LTR and in the location between downstream of entire the 5' LTR and the initial translation site have been identified by mobilityshift binding assays and DNase I footprinting assays. The data reveals three protected regions: a TATA-binding site, the AT-1, and AT-2 binding sites. The TATA-binding site and AT-1 site are …

The Effects Of Teratogens On Serotonin Expression In Drosophila Embryonic Cell Cultures, Keri Joel Hopkins

Theses Digitization Project

No abstract provided.

Abnormal Chromatin (Abc), A Maternal-Effect Locus In Drosophila Melanogaster, Kristin B. Vessey, Rachael L. Ludwiczak, Amy S. Briot, Eileen M. Underwood

Eileen M. Underwood

Mutations in the maternal-effect gene abnormal chromatin (abc) in Drosophila melanogaster result in a variety of defects involving nuclear replication/division. Three recessive alleles of this gene, which maps near 51F on chromosome 2, all result in female sterility. They cause slower embryonic development that is usually abnormal from the earliest nuclear divisions and arrested by the sixth one. Nuclei tend to be large and erratically distributed, some intensely staining. Mitotic asynchrony is common. Few embryos reach the gastrula stage and none hatch. With the weakest allele, fsPL, bridges between nuclei are common; abnormal chromatin clumps that resemble yolk nuclei occur …

Effects Of Chemical Aneuploidogens On Taxol Purified Drosophila And Mouse Brain Microtubules Polymerization And Depolymerization In Vitro, Anil Sehgal

Biological Sciences Theses & Dissertations

The effects of aneuploidogens (aneuploidy causing agents) on taxol-purified microtubules from Drosophila and mouse brain in vitro were studied by using a spectrophotometric assay and electron microscopy. Colchicine, acetonitrile, propionitrile, acrylonitrile, dimethyl sulfoxide (DMSO), griseofulvin and cadmium chloride inhibited microtubule polymerization whereas methoxyethyl acetate (MEA) and methyl mercuric chloride (MMC) did not. All aneuploidogens tested (at 50mM) resulted in reduced rate of elongation of mouse brain microtubules. MMC, cadmium chloride and DMSO resulted in increased rates of Drosophila microtubule elongation whereas the rest of the drugs resulted in decreases. The in vitro results from Drosophila correlate well with the previously …

The Functional Organization Of The Vestigial Locus In Drosophila Melanogaster, Jim A. Williams, Audrey L. Atkin, John B. Bell

School of Biological Sciences: Faculty Publications

Vestigial mutants are associated with imaginal disc cell death which results in the deletion of adult wing and haltere structures. The vestigial locus has previously been cloned, and mutational lesions associated with a number of vg alleles were mapped within a 19 kb DNA region defined as essential for vg function. Herein we report the identification and characterization of a developmentally regu-lated 3.8 kb vg transcript which is spliced from exons distributed throughout the essential interval defined above. All the characterized classical alleles have predictable effects on this transcription unit, and the severity of this effect is directly proportional to …

Genespeak: [Dr. Michael W. Young], None None

Rockefeller University Research Profiles

Rockefeller University Research Profiles are a series of scientific profiles that were published quarterly, from 1980-1990, by the Rockefeller University. Each issue features the research and achievements of an individual Rockefeller University scientist.

The Isolation Of Ecdysterone Inducible Genes By Hybridization Subtraction Chromatography, Michael P. Vitek, Susan G. Kreissman, Robert H. Gross

Dartmouth Scholarship

We have developed a procedure for selectively enriching a mRNA population for inducible sequences. Other than the induced mRNA species, the population of mRNA in control cells is approximately the same as the mRNA population in induced cells. Cytoplasmic mRNA from control cells is bound to oligo (dT)-cellulose and used as a template for reverse transcriptase, the oligo (dT) serving as a primer. After removing the template mRNAs, the cDNA-cellulose column is used to hybridize a population of mRNAs from induced cells. The non-hybridized poly A ⁺ RNAs are greatly enriched in the inducible sequences. We have used this technique …

The Effect Of Temperature On The Life Cycle Of Drosophila Acutilabella, Donald A. Miles

University of the Pacific Theses and Dissertations

This is a study of the rate of development of the fly, Drosophila acutilabelle, Stalker (1953), at three temperatures, 22°, 25°, and 28°C. It is part of a larger project testing the hypothesis that stenothermal species (those restricted to a narrow temperature range) are more sensitive than eurythermal species, such a the cosmopolitan D. melanogaster and D. hydei (those able to live over a broad temperature range) to the effects of temperature during development. It has been suggested that eurythermal species have a lower Q₁₀ of development. The species used in this study is considered to be stenothermal because …

The Effect Of Temperature On The Life Cycle Of Drosophila Nebulosa, Scott S. Nagatani

University of the Pacific Theses and Dissertations

It is the purpose of this research to study the effect of temperature on the life cycle of D. nebulosa. D. nebulosa is considered a stenothermal species from a warm environment and has been reported in Texas and Florida, the West Indies, Mexico, Central America, and as far south as Brazil. According to the hypothesis of Hunter (1964), the capacity of this species for adaptation to different temperatures would not be expected to be as great as that of a eurythermal species. Stenothermal species are relatively limited by the environmental temperature, and therefore, one would expect a marked decrease in …

The Life Cycle Of Seven Species Of Drosophila, Miriam Marquez Marin De Flores

University of the Pacific Theses and Dissertations

The purpose of this work is to determine the life cycle of different species of Drosophila of different subgenera and coming from different environments.

The "Starvation Effect" And Tryptophan Pyrrolase Activity In The Vermilion Mutant Of Drosophila, Ernest E. Shelton Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The enzyme tryptophan pyrrolase is controlled by the vermilion locus in Drosophila melanogaster and is normally lacking in the vermilion mutants. During this investigation it has been demonstrated that v¹;bw flies have tryptophan pyrrolase activity when grown under near starvation conditions.

During development of the fly there is a peak of enzyme activity in the early third instar soon after the transfer to starvation medium. A second peak of enzyme activity occurs during the pupal stage. The activity in v¹;bw pupae is about 15% of the activity found in cn bw adults.

In v …

Campaniform Sensilla Patterns On The Wings Of Drosophila, Charles L. Hamrum, Arthur W. Glass, Vern Sisson

Journal of the Minnesota Academy of Science

Campaniform sensilla have been described from the wings, mouthparts, legs, and other parts of the insect body. These small sense organs were known under several terms until Berlese ( 1909) applied the term "campaniformi" because of their dome, or bell-shaped character. Numerous functions have been suggested for these organs which seem to be stress receptors of some sort. Very few attempts have been made to utilize these sensilla as taxonomic characters.