Map positions of third chromosomal female sterile and lethal mutations of Drosophila melanogaster

Chromosomal mutations induced by ethyl methanesulfonate (EMS) treatment can cause female sterility or maternal-effect lethality in Drosophila. EMS is particularly useful to researchers because it creates mutations independent of position effects. However, because researchers have little control over the chromosomal site of mutation, post-mutagenic genetic mapping is required to determine the cytological location of the mutation. To make a valuable set of mutants more useful to the research community, we have mapped the uncharacterized part of the female-sterile – maternal-effect lethal Tübingen collection. We mapped 49 female-sterile – maternal-effect lethal alleles and 72 lethal alleles to individual deficiency intervals on the third chromosome. In addition, we analyzed the phenotype of ovaries resulting from female sterile mutations. The observed phenotypes range from tumorous ovaries and early blocks in oogenesis, to later blocks, slow growth, blocks in stage 10, to apparently full development of the ovary. The mapping and phenotypic characterization of these 121 mutations provide the necessary information for the researcher to consider a specific mutant as a candidate for their gene of interest.Key words: Drosophila melanogaster, oogenesis, female sterile, maternal-effect lethal, EMS-induced mutations.

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Cytoplasmic dynein (ddlc1) mutations cause morphogenetic defects and apoptotic cell death in Drosophila melanogaster.

Molecular and Cellular Biology ◽

10.1128/mcb.16.5.1966 ◽

1996 ◽

Vol 16 (5) ◽

pp. 1966-1977 ◽

Cited By ~ 104

Author(s):

T Dick ◽

K Ray ◽

H K Salz ◽

W Chia

Keyword(s):

Drosophila Melanogaster ◽

Light Chain ◽

Blot Analysis ◽

Cytoplasmic Dynein ◽

P Element ◽

Female Sterility ◽

Dynein Light Chain ◽

Loss Of Function ◽

Light Chain Gene

We report the molecular and genetic characterization of the cytoplasmic dynein light-chain gene, ddlc1, from Drosophila melanogaster. ddlc1 encodes the first cytoplasmic dynein light chain identified, and its genetic analysis represents the first in vivo characterization of cytoplasmic dynein function in higher eucaryotes. The ddlc1 gene maps to 4E1-2 and encodes an 89-amino-acid polypeptide with a high similarity to the axonemal 8-kDa outer-arm dynein light chain from Chlamydomonas flagella. Developmental Northern (RNA) blot analysis and ovary and embryo RNA in situ hybridizations indicate that the ddlc1 gene is expressed ubiquitously. Anti-DDLC1 antibody analyses show that the DDLC1 protein is localized in the cytoplasm. P-element-induced partial-loss-of-function mutations cause pleiotropic morphogenetic defects in bristle and wing development, as well as in oogenesis, and hence result in female sterility. The morphological abnormalities found in the ovaries are always associated with a loss of cellular shape and structure, as visualized by a disorganization of the actin cytoskeleton. Total-loss-of-function mutations cause lethality. A large proportion of mutant animals degenerate during embryogenesis, and the dying cells show morphological changes characteristic of apoptosis, namely, cell and nuclear condensation and fragmentation, as well as DNA degradation. Cloning of the human homolog of the ddlc1 gene, hdlc1, demonstrates that the dynein light-chain 1 is highly conserved in flies and humans. Northern blot analysis and epitope tagging show that the hdlc1 gene is ubiquitously expressed and that the human dynein light chain 1 is localized in the cytoplasm. hdlc1 maps to 14q24.

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Genotypic and Phenotypic Characterization of Treponema phagedenis from Bovine Digital Dermatitis

Microorganisms ◽

10.3390/microorganisms8101520 ◽

2020 ◽

Vol 8 (10) ◽

pp. 1520

Author(s):

Hector M. Espiritu ◽

Lovelia L. Mamuad ◽

Su-jeong Jin ◽

Seon-ho Kim ◽

Seok-won Kwon ◽

...

Keyword(s):

Slow Growth ◽

Small Difference ◽

Phenotypic Characterization ◽

Average Nucleotide Identity ◽

Digital Dermatitis ◽

16S Rrna Analysis ◽

Single Strain ◽

Low Concentrations ◽

Bovine Strain

This study aimed to isolate and characterize Treponema spp. from bovine digital dermatitis (BDD)-infected dairy cattle. Seven isolates were characterized in this study. Isolates exhibited slow growth, and colonies penetrated the agar and exhibited weak β-hemolysis. Round bodies were observed in old and antibiotic-treated cultures. Cells ranged from 9–12 µm in length, 0.2–2.5 µm in width, and were moderately spiraled. The 16S rRNA analysis revealed the isolates as Treponema phagedenis with >99% sequence homology. Isolates had alkaline phosphatase, acid phosphatase, β-galactosidase, N-acetyl-β-glucosaminidase, esterase (C4), esterase lipase (C8), naphthol-AS-BI-phosphohydrolase, and β-glucuronidase activities. Low concentrations of ampicillin, erythromycin, and tetracycline were required to inhibit the growth of isolates. Formic, acetic, and butyric acids were produced, while propionic acid was significantly utilized, indicating its essentiality for treponemal growth. The isolates shared the same characteristics and, therefore, were considered as a single strain. Isolate HNL4 was deposited as a representative isolate (Treponema phagedenis KS1). The average nucleotide identity of strain KS1 showed a small difference with the human strain (99.14%) compared with bovine strain (99.72%). This study was the first to isolate and characterize Treponema phagedenis from BDD in Korea and, hence, it delivered pathogenicity-related insights and provided valuable information that can be used for the management of BDD.

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Identification and Characterization of Breakpoints and Mutations on Drosophila melanogaster Balancer Chromosomes

G3 Genes|Genome|Genetics ◽

10.1534/g3.120.401559 ◽

2020 ◽

Vol 10 (11) ◽

pp. 4271-4285 ◽

Cited By ~ 2

Author(s):

Danny E. Miller ◽

Lily Kahsai ◽

Kasun Buddika ◽

Michael J. Dixon ◽

Bernard Y. Kim ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Repetitive Sequences ◽

Intestinal Cell ◽

Induced Mutations ◽

Telomeric Sequences ◽

Long Read ◽

The Stability ◽

Induced Apoptosis ◽

Balancer Chromosomes

Balancers are rearranged chromosomes used in Drosophila melanogaster to maintain deleterious mutations in stable populations, preserve sets of linked genetic elements and construct complex experimental stocks. Here, we assess the phenotypes associated with breakpoint-induced mutations on commonly used third chromosome balancers and show remarkably few deleterious effects. We demonstrate that a breakpoint in p53 causes loss of radiation-induced apoptosis and a breakpoint in Fucosyltransferase A causes loss of fucosylation in nervous and intestinal tissue—the latter study providing new markers for intestinal cell identity and challenging previous conclusions about the regulation of fucosylation. We also describe thousands of potentially harmful mutations shared among X or third chromosome balancers, or unique to specific balancers, including an Ankyrin 2 mutation present on most TM3 balancers, and reiterate the risks of using balancers as experimental controls. We used long-read sequencing to confirm or refine the positions of two inversions with breakpoints lying in repetitive sequences and provide evidence that one of the inversions, In(2L)Cy, arose by ectopic recombination between foldback transposon insertions and the other, In(3R)C, cleanly separates subtelomeric and telomeric sequences and moves the subtelomeric sequences to an internal chromosome position. In addition, our characterization of In(3R)C shows that balancers may be polymorphic for terminal deletions. Finally, we present evidence that extremely distal mutations on balancers can add to the stability of stocks whose purpose is to maintain homologous chromosomes carrying mutations in distal genes. Overall, these studies add to our understanding of the structure, diversity and effectiveness of balancer chromosomes.

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Viable maternal-effect mutations that affect the development of the nematode Caenorhabditis elegans.

Genetics ◽

10.1093/genetics/141.4.1351 ◽

1995 ◽

Vol 141 (4) ◽

pp. 1351-1364 ◽

Cited By ~ 8

Author(s):

S Hekimi ◽

P Boutis ◽

B Lakowski

Keyword(s):

Quantitative Analysis ◽

Caenorhabditis Elegans ◽

Maternal Effect ◽

Genetic Screen ◽

Phenotypic Characterization ◽

Nematode Caenorhabditis Elegans ◽

Critical Function ◽

Complementation Groups

Abstract We carried out a genetic screen for viable maternal-effect mutants to identify genes with a critical function relatively early in development. This type of mutation would not have been identified readily in previous screens for viable mutants and therefore could define previously unidentified genes. We screened 30,000 genomes and identified 41 mutations falling into 24 complementation groups. We genetically mapped these 24 loci; only two of them appear to correspond to previously identified genes. We present a partial phenotypic characterization of the mutants and a quantitative analysis of the degree to which they can be maternally or zygotically rescued.

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Characterization of Suppressor of fused, a complete suppressor of the fused segment polarity gene of Drosophila melanogaster.

Genetics ◽

10.1093/genetics/132.3.725 ◽

1992 ◽

Vol 132 (3) ◽

pp. 725-736 ◽

Cited By ~ 6

Author(s):

T Préat

Keyword(s):

Drosophila Melanogaster ◽

Maternal Effect ◽

Opposite Effect ◽

Loss Of Function ◽

Suppressor Of Fused ◽

Segment Polarity ◽

New Gene ◽

Segment Polarity Gene ◽

Polarity Gene

Abstract fused (fu) is a maternal effect segment polarity gene of Drosophila melanogaster. In addition, fu females have tumorous ovaries. Two ethyl methanesulfonate mutageneses were carried out in order to isolate suppressors of the fu phenotype. A new gene, Suppressor of fused (Su(fu)), was identified. It is located in the 87C8 region of the third chromosome. Su(fu) displays a maternal effect and is also expressed later in development. Although Su(fu)LP is a complete loss-of-function mutation, it is homozygous viable and has no phenotype by itself. Su(fu) fully suppresses the embryonic and adult phenotypes of fu mutants. Su(fu) mutations are semidominant and a Su(fu)+ duplication has an opposite effect, enhancing the fused phenotype. It is proposed therefore that the Su(fu)+ product is involved in the same developmental step as the Fu+ kinase. Thus, a new gene interacting with the segment polarity pathway was identified using an indirect approach.

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Isolation and characterization of dominant female sterile mutations of Drosophila melanogaster. I. Mutations on the third chromosome.

Genetics ◽

10.1093/genetics/122.1.111 ◽

1989 ◽

Vol 122 (1) ◽

pp. 111-127 ◽

Cited By ~ 1

Author(s):

M Erdélyi ◽

J Szabad

Keyword(s):

Drosophila Melanogaster ◽

Germ Line ◽

Female Sterility ◽

Male Germ Line ◽

The Third ◽

Egg Retention ◽

Isolation And Characterization ◽

Dominant Female ◽

New Alleles

Abstract Fifty-one dominant female sterile (Fs) mutations linked to the third chromosome of Drosophila melanogaster are described. EMS induced Fs mutations arise with the frequency of one Fs per about 2500 recessive lethals. Complementation analysis of the revertants showed that these Fs mutations represent 27-34 loci, about 60% of the third chromosome units mutable to dominant female sterility by EMS. The Fs mutations were mapped on the basis of mitotic recombination induced in the female (in 16 cases also in the male) germ-line. Behavior of the revertants and the Fs+ germ-line clones demonstrate the gain-of-function nature of the Fs alleles. With two exceptions, the Fs(3) mutations are germ-line dependent. Novel phenotypes appeared in most of the Fs mutations. With eight exceptions, the Fs(3) mutations are fully penetrant, in some cases with variable expressivity. One of the Fs(3) mutations is a non-ovary-dependent egg retention mutation, two others alter egg shape, and 27 bring about arrest in development at about the time of fertilization. In 21 of the Fs(3) mutations embryos develop to the larval stage of differentiation; this group includes 5 new alleles of Toll and 4 of easter.

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Genotypic and Phenotypic Characterization of the Drosophila melanogaster Olfactory Mutation Indifferent

Genetics ◽

10.1093/genetics/144.4.1577 ◽

1996 ◽

Vol 144 (4) ◽

pp. 1577-1587

Author(s):

Matthew Cobb

Keyword(s):

Drosophila Melanogaster ◽

Methyl Esters ◽

Phenotypic Characterization ◽

Deletion Mapping ◽

Wild Type ◽

Induced Mutations ◽

Olfactory Responses ◽

Mutant Character ◽

Type Character ◽

The Right

Two Drosophila melanogaster third chromosomes carrying the EMS-induced mutations IndifferentA (IndfA) and IndifferentB (IndfB), previously isolated from larvae showing an anosmia when stimulated with nonanol, were recombined with a multi-marked chromosome in order to localize the mutant character(s). Recombinant strains were tested for their larval olfactory responses and classed as either mutant or wild type; both Indf characters were found to be located on the right arm of the chromosome, between ebony and claret. Deletion mapping suggests that the Indifferent wild-type character is a haplo-insufficiency and that IndfA and IndfB are located in cytological region 96A2-7. Deficiencies and both mutant strains were tested with 14 closely related odors (alcohols, acetates, acids and methyl esters, between eight and 10 carbons long). When stimulated with methyl octanoate, IndfA and IndfB appeared recessive; noncomplementation was observed for this phenotype in IndfA/IndfB hybrids indicating that the two characters are allelic. The overall responses of IndfA, IndfB and the deficiencies indicate that Indf is involved in processing organic odors of between eight and 10 carbons in length.

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NON-MENDELIAN FEMALE STERILITY IN DROSOPHILA MELANOGASTER: CHARACTERIZATION OF THE NONINDUCER CHROMOSOMES OF INDUCER STRAINS

Genetics ◽

10.1093/genetics/91.3.473 ◽

1979 ◽

Vol 91 (3) ◽

pp. 473-489

Author(s):

Georges Picard ◽

Alain Pelisson

Keyword(s):

Drosophila Melanogaster ◽

Genetic Recombination ◽

Female Sterility ◽

Chromosome 2 ◽

Genetic Element ◽

Mendelian Segregation ◽

Factor I ◽

I Factor ◽

Males And Females

ABSTRACT In relation to non-Mendelian female sterility, Drosophila melanogaster strains can be divided into two main classes, inducer and reactive. The genetic element responsible for the inducer condition (I factor) is chromosomal and may be linked to any inducer-strain chromosome. Each chromosome carrying the I factor (i + chromosome) can, when introduced by the paternal gamete into a reactive oocyte, give rise to females (denoted SF) showing more-or-less reduced fertility. As long as i + chromosomes are transmitted through heterozygous males with reactive originating chromosomes (r chromosomes), I factor follows Mendelian segregation patterns. In contrast, in heterozygous i+/r females, a varying proportion of r chromosomes may irreversibly acquire I factor, independently of classical genetic recombination, by a process called chromosomal contamination. The contaminated reactive chromosomes behave as i + chromosomes.—In the present paper, evidence is given that the Luminy inducer strain displays a polymorphism for two kinds of second chromosomes. Some of them are i +, while others, denoted io, are unable t3 induce any SF sterility when introduced by paternal gametes into reactive oocytes. They are also unable to induce contamination of r chromosomes, but, like r chromosomes, they may be contaminated by i+ chromosomes in SF or RSF females. The study of the segregation of i + and io second chromosomes in the progeny of heterozygous Luminy males and females leads to the conclusion that on chromosome 2 of the Luminy stock the I factor is at a single locus. —XI second and third io chromosomes have been found in several inducer strains. Since these chromosomes can be maintained with i + chromosomes in inducer strains in spite of their ability to be contaminated in RSF females, it can be concluded that chromosomal contamination does not take place in females of inducer strains. This implies that contamination occurs only in cells having cytoplasm in a reactive state.

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The Drosophila melanogaster ade5 Gene Encodes a Bifunctional Enzyme for Two Steps in the de novo Purine Synthesis Pathway

Genetics ◽

10.1093/genetics/154.3.1239 ◽

2000 ◽

Vol 154 (3) ◽

pp. 1239-1253

Author(s):

Allyson F O'Donnell ◽

Stanley Tiong ◽

David Nash ◽

Denise V Clark

Keyword(s):

Drosophila Melanogaster ◽

De Novo ◽

Single Gene ◽

Hybrid Dysgenesis ◽

Induced Mutations ◽

Gene Encoding ◽

Purine Synthesis ◽

E Coli ◽

Gene Maps

Abstract Steps 6 and 7 of de novo purine synthesis are performed by 5-aminoimidazole ribonucleotide carboxylase (AIRc) and 4-[(N-succinylamino)carbonyl]-5-aminoimidazole ribonucleotide synthetase (SAICARs), respectively. In vertebrates, a single gene encodes AIRc-SAICARs with domains homologous to Escherichia coli PurE and PurC. We have isolated an AIRc-SAICARs cDNA from Drosophila melanogaster via functional complementation with an E. coli purC purine auxotroph. This cDNA encodes AIRc yet is unable to complement an E. coli purE mutant, suggesting functional differences between Drosophila and E. coli AIRc. In vertebrates, the AIRc-SAICARs gene shares a promoter region with the gene encoding phosphoribosylamidotransferase, which performs the first step in de novo purine synthesis. In Drosophila, the AIRc-SAICARs gene maps to section 11B4-14 of the X chromosome, while the phosphoribosylamidotransferase gene (Prat) maps to chromosome 3; thus, the close linkage of these two genes is not conserved in flies. Three EMS-induced X-linked adenine auxotrophic mutations, ade41, ade51, and ade52, were isolated. Two gammaradiation-induced (ade53 and ade54) and three hybrid dysgenesis-induced (ade55, ade56, and ade58) alleles were also isolated. Characterization of the auxotrophy and the finding that the hybrid dysgenesis-induced mutations all harbor P transposon sequences within the AIRc-SAICARs gene show that ade5 encodes AIRc-SAICARs.

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TheAspergillus nidulans musNGene Encodes a RecQ Helicase That Interacts With the PI-3K-Related Kinase UVSB

Genetics ◽

10.1093/genetics/159.4.1595 ◽

2001 ◽

Vol 159 (4) ◽

pp. 1595-1604 ◽

Cited By ~ 3

Author(s):

Amy F Hofmann ◽

Steven D Harris

Keyword(s):

Dna Damage ◽

Homologous Recombination ◽

Dna Damage Response ◽

Slow Growth ◽

Phenotypic Characterization ◽

Null Mutant ◽

Recq Helicase ◽

Present Evidence ◽

Damage Response

AbstractIn Aspergillus nidulans, the uvsB gene encodes a member of the PI-3K-related kinase family of proteins. We have recently shown that UVSB is required for multiple aspects of the DNA damage response. Since the musN227 mutation is capable of partially suppressing defects caused by uvsB mutations, we sought to understand the mechanism underlying the suppression by cloning the musN gene. Here, we report that musN encodes a RecQ helicase with homology to S. pombe rqh1, S. cerevisiae sgs1, and human BLM and WRN. Phenotypic characterization of musN mutant alleles reveals that MUSN participates in the response to a variety of genotoxic agents. The slow growth and genotoxin sensitivity of a musN null mutant can be partially suppressed by a defect in homologous recombination caused by the uvsC114 mutation. In addition, we present evidence suggesting that MUSN may promote recovery from the DNA damage response. We suggest that a block to recovery caused by the musN227 mutation, coupled with the modest accumulation of recombination intermediates, can suppress defects caused by uvsB mutations. Finally, we report that another RecQ helicase, ORQA, performs a function that partially overlaps that of MUSN.

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