Deletion of the ecdysis-triggering hormone gene leads to lethal ecdysis deficiency

Development ◽  
2002 ◽  
Vol 129 (2) ◽  
pp. 493-503 ◽  
Author(s):  
Yoonseong Park ◽  
Valery Filippov ◽  
Sarjeet S. Gill ◽  
Michael E. Adams
Keyword(s):  
Genetic Analysis ◽  
Respiratory System ◽  
Larval Instar ◽  
Gene Products ◽  
Behavioral Sequence ◽  
Signaling System ◽  
Gene Encoding ◽  
Its Gene ◽  
Ecdysis Triggering Hormone ◽  
Null Mutants

At the end of each developmental stage, insects perform a stereotypic behavioral sequence leading to ecdysis of the old cuticle. While ecdysis-triggering hormone (ETH) is sufficient to trigger this sequence, it has remained unclear whether it is required. We show that deletion of eth, the gene encoding ETH in Drosophila, leads to lethal behavioral and physiological deficits. Null mutants (eth–) fail to inflate the new respiratory system on schedule, do not perform the ecdysis behavioral sequence, and exhibit the phenotype buttoned-up, which is characterized by incomplete ecdysis and 98% mortality at the transition from first to second larval instar. Precisely timed injection of synthetic DmETH1 restores all deficits and allows normal ecdysis to occur. These findings establish obligatory roles for eth and its gene products in initiation and regulation of the ecdysis sequence. The ETH signaling system provides an opportunity for genetic analysis of a chemically coded physiological and behavioral sequence.

scholarly journals Identification of the Gene Encoding Sulfopyruvate Decarboxylase, an Enzyme Involved in Biosynthesis of Coenzyme M

2000 ◽  
Vol 182 (17) ◽  
pp. 4862-4867 ◽  
Author(s):  
Marion Graupner ◽  
Huimin Xu ◽  
Robert H. White
Keyword(s):  
Escherichia Coli ◽  
Second Step ◽  
Gene Products ◽  
Methanococcus Jannaschii ◽  
Coenzyme M ◽  
Gene Encoding ◽  
Fourth Step

ABSTRACT The products of two adjacent genes in the chromosome ofMethanococcus jannaschii are similar to the amino and carboxyl halves of phosphonopyruvate decarboxylase, the enzyme that catalyzes the second step of fosfomycin biosynthesis inStreptomyces wedmorensis. These two M. jannaschii genes were recombinantly expressed inEscherichia coli, and their gene products were tested for the ability to catalyze the decarboxylation of a series of α-ketoacids. Both subunits are required to form an α6β6 dodecamer that specifically catalyzes the decarboxylation of sulfopyruvic acid to sulfoacetaldehyde. This transformation is the fourth step in the biosynthesis of coenzyme M, a crucial cofactor in methanogenesis and aliphatic alkene metabolism. The M. jannaschiisulfopyruvate decarboxylase was found to be inactivated by oxygen and reactivated by reduction with dithionite. The two subunits, designated ComD and ComE, comprise the first enzyme for the biosynthesis of coenzyme M to be described.

Deletions in the C-terminal coding region of the v-sis gene: dimerization is required for transformation

1986 ◽  
Vol 6 (4) ◽  
pp. 1304-1314
Author(s):  
M Hannink ◽  
M K Sauer ◽  
D J Donoghue
Keyword(s):  
Growth Factor ◽  
Gene Product ◽  
Platelet Derived Growth Factor ◽  
Deletion Mutants ◽  
Gene Products ◽  
Coding Region ◽  
Strong Connection ◽  
C Terminus ◽  
Its Gene ◽  
Transforming Gene

The v-sis gene encodes chain B of platelet-derived growth factor. However, this gene codes for additional amino acids at both the N terminus and the C terminus of its gene product which are not present in the amino acid sequence of platelet-derived growth factor. We constructed a series of deletion mutants with deletions in the v-sis gene in order to define the C-terminal limit of the v-sis gene product which is required for transformation. Deletion mutants of the v-sis gene which encoded truncated gene products up to 57 residues shorter than the v-siswt gene product were still able to transform cells. The minimal transforming region of the v-sis gene product contained six residues fewer than were present in chain B of platelet-derived growth factor. Only 10 residues, including the sequence Cys-Lys-Cys, separated the smallest transforming gene product from the largest nontransforming gene product. These cysteine residues were also important for dimerization of the v-sis gene product, since all of the nontransforming v-sis deletions were unable to form dimers when they were analyzed under nonreducing conditions. Our results suggest that there is a strong connection between transformation and dimerization.

Nonequivalent requirements for PS1 and PS2 integrin at cell attachments in Drosophila: genetic analysis of the alpha PS1 integrin subunit

Development ◽  
1995 ◽  
Vol 121 (5) ◽  
pp. 1311-1320 ◽  
Author(s):  
D.L. Brower ◽  
T.A. Bunch ◽  
L. Mukai ◽  
T.E. Adamson ◽  
M. Wehrli ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Clonal Analysis ◽  
Wing Surface ◽  
Myotendinous Junction ◽  
Integrin Subunit ◽  
Chromosome Break ◽  
Gene Encoding ◽  
Tendon Cells ◽  
Eye Morphogenesis ◽  
Somatic Muscles

We report on the generation and phenotype of mutant alleles of multiple edematous wings (mew), the gene encoding the alpha PS1 subunit of the PS1 integrin of Drosophila. None of the six alleles examined makes detectable protein, and one allele results from a chromosome break near the middle of the translated sequence, so we are confident that we have described the null phenotype. In contrast to if (alpha PS2) and mys (beta PS) mutants, most mutant mew embryos hatch, to die as larvae. Mutant mew embryos display abnormal gut morphogenesis but, unlike mys or if embryos, there is no evidence of defects in the somatic muscles. Thus, the complementary distributions of PS1 (alpha PS1 beta PS) and PS2 (alpha PS2 beta PS) integrin on tendon cells and muscle, respectively, do not reflect equivalent requirements at the myotendinous junction. Dorsal herniation, characteristic of the mys lethal phenotype, is not observed in mew or in mew if embryos. Clonal analysis experiments indicate that eye morphogenesis is disrupted in mew clones, but if clones in the eye are relatively normal in morphology. Adult wings display blisters around large dorsal but not ventral mew clones. In contrast to dorsal mys clones, small mew patches do not necessarily display morphogenetic abnormalities. Thus, another integrin in addition to PS1 appears to function on the dorsal wing surface.

Genetic Analysis of a Cyanobacterial Gene Encoding a Membrane Protein Which Accumulates Under Iron Stress

1987 ◽  
pp. 773-776 ◽  
Author(s):  
Louis A. Sherman ◽  
K. J. Reddy ◽  
H. C. Riethman ◽  
George S. Bullerjahn
Keyword(s):  
Membrane Protein ◽  
Genetic Analysis ◽  
Iron Stress ◽  
Gene Encoding ◽  
Cyanobacterial Gene

scholarly journals Premature Moustache As Presenting Symptom of Nonclassic Congenital Adrenal Hyperplasia due to 2 Uncommon Mutations of theCYP21A2Gene

2011 ◽  
Vol 2011 ◽  
pp. 1-3 ◽  
Author(s):  
Guy Massa ◽  
Philippe Gillis ◽  
Marianne Schwartz
Keyword(s):  
Genetic Analysis ◽  
Congenital Adrenal Hyperplasia ◽  
Adrenal Hyperplasia ◽  
Gene Encoding ◽  
Rare Mutations

A Turkish boy was referred at the age of 3 6/12 years for the evaluation of a premature moustache. No other signs of virilisation were present. The endocrine evaluation led to the diagnosis of nonclassic congenital adrenal hyperplasia. Genetic analysis revealed 2 rare mutations of theCYP21A2gene, the gene encoding for the 21-hydroxylase enzyme: a recently reported R132C mutation in exon 3 and a R339H mutation in exon 8, both reported in the nonclassic CAH. An early moustache, for which the term premature moustache can be coined, can be the presenting symptom of nonclassic CAH. In all children presenting with a sex or age inappropriate development of a moustache, an endocrine evaluation is indicated.

scholarly journals Mls is not a single gene, allelic system. Different stimulatory Mls determinants are the products of at least two nonallelic, unlinked genes.

1987 ◽  
Vol 166 (4) ◽  
pp. 1150-1155 ◽  
Author(s):  
R Abe ◽  
J J Ryan ◽  
R J Hodes
Keyword(s):  
T Cells ◽  
Single Gene ◽  
Surface Structures ◽  
Chromosome 1 ◽  
Gene Products ◽  
Spleen Cells ◽  
Gene Encoding ◽  
Cell Surface Structures ◽  
Genes Encoding ◽  
Polymorphic Cell

Mls determinants share with MHC products the unique property of stimulating T cells at extraordinarily high precursor frequencies. The Mls system was originally described as a single locus on chromosome 1, with four alleles, Mlsa, Mlsb, Mlsc, and Mlsd, that encode polymorphic cell surface structures. However, the fundamental issues of polymorphism and allelism in the Mls system remain controversial. To clarify these questions, a formal segregation analysis of the genes encoding Mlsa and Mlsc determinants was carried out by testing the capacity of spleen cells from progeny of (Mlsa X Mlsc)F1 X Mlsb breedings to stimulate responses by unprimed T cells and by Mlsa- and Mlsc-specific cloned T cells. The results of this analysis indicated that the gene encoding Mlsa determinants is neither allelic to nor linked to the gene encoding Mlsc determinants. Together with previous findings, these results also suggest that another strongly stimulatory type, Mlsd, in fact results from the independent expression of unlinked Mlsa and Mlsc gene products. Based on these observations, it is concluded that, contrary to conventional concepts, the stimulatory phenotypes designated as Mlsa, Mlsc, and Mlsd can be accounted for by the independent expression of the products of at least two unlinked gene loci.

The genetic analysis of new Polish strains of European brown hare syndrome virus

2014 ◽  
Vol 17 (2) ◽  
pp. 353-355
Author(s):  
E. Kwit ◽  
M. Chrobocińska ◽  
Z. Grądzki ◽  
Ł. Jarosz ◽  
B. Majer-Dziedzic ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Phylogenetic Position ◽  
Brown Hare ◽  
Gene Encoding ◽  
European Brown Hare ◽  
Close Relationship ◽  
Provinces Of Poland ◽  
Pcr Method ◽  
European Brown Hare Syndrome ◽  
Hare Population

Abstract In this paper we describe recently occurring outbreaks of European brown hare syndrome (EBHS) in a captive hare population. The aim of our study was to evaluate the phylogenetic position of detected Polish strains compared to other European strains of EBHSV. Investigations were undertaken in hares from different provinces of Poland. Liver or spleen samples were tested for viral RNA using the RT-nested PCR method and the products were subsequently sequenced. The genetic analysis was based on the fragment of gene encoding viral capsid protein; it revealed a high homology and close relationship between Polish and European EBHSV strains isolated between 2001 and 2011

A genetic analysis of the alpha-glycerophosphate oxidase locus in Drosophila melanogaster.

Genetics ◽  
1988 ◽  
Vol 120 (3) ◽  
pp. 755-766
Author(s):  
M B Davis ◽  
R J MacIntyre
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Analysis ◽  
Structural Gene ◽  
Mitochondrial Enzyme ◽  
Synthetic Lethal ◽  
Lethal Phenotype ◽  
Cytoplasmic Enzyme ◽  
Glycerophosphate Dehydrogenase ◽  
Null Mutants

Abstract The gene for alpha-glycerophosphate oxidase, the nuclear encoded mitochondrial enzyme of the alpha-glycerophosphate cycle (alpha GP); has been mapped in Drosophila melanogaster. Several interstitial deficiencies in region 50c-53AB of chromosome 2R were used to localize the structural gene to 52D2-5. In addition, mutations of alpha GPO were generated; alpha GPO mutants are viable yet flightless. Interactions of alpha GPO with alpha-glycerophosphate dehydrogenase (alpha GPDH), the cytoplasmic enzyme of the alpha GP cycle, were investigated through the synthesis of a series of alpha GPDHnull-alpha GPOnull double mutants. Of the six double null mutants constructed, four alpha GPDH-alpha GPO double nulls are viable and flightless. Two double mutants, however, exhibit an allelic-dependent synthetic lethal phenotype.

scholarly journals Exploitation of a “hockey-puck” phenotype to identify pilus and biofilm regulators in Serratia marcescens through genetic analysis

2016 ◽  
Vol 62 (1) ◽  
pp. 83-93 ◽  
Author(s):  
Robert M.Q. Shanks ◽  
Nicholas A. Stella ◽  
Kimberly M. Brothers ◽  
Denise M. Polaski
Keyword(s):  
Genetic Analysis ◽  
Serratia Marcescens ◽  
Candidate Genes ◽  
Biofilm Formation ◽  
Type I ◽  
Relative Importance ◽  
Gene Encoding ◽  
Uncharacterized Gene ◽  
Mutation Screen

Pili are essential adhesive determinants for many bacterial pathogens. A suppressor mutation screen that takes advantage of a pilus-mediated self-aggregative “hockey-puck” colony phenotype was designed to identify novel regulators of type I pili in Serratia marcescens. Mutations that decreased pilus biosynthesis mapped to the fimABCD operon; to the genes alaT, fkpA, and oxyR; upstream of the flagellar master regulator operon flhDC; and to an uncharacterized gene encoding a predicted DUF1401 domain. Biofilm formation and pilus-dependent agglutination assays were used to characterize the relative importance of the identified genes in pilus biosynthesis. Additional mutagenic or complementation analysis was used to verify the role of candidate genes in pilus biosynthesis. Presented data support a model that CRP negatively regulates pilus biosynthesis through increased expression of flhDC and decreased expression of oxyR. Further studies are warranted to determine the mechanism by which these genes mediate pilus biosynthesis or function.

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