Genetic Localization of a Drosophila melanogaster Resistance Gene to a Parasitoid Wasp and Physical Mapping of the Region

Drosophila melanogaster larvae usually react against eggs of the parasitoid wasp Leptopilina boulardi by surrounding them with a multicellular melanotic capsule. The genetic determinism of this response has been studied previously using susceptible (non-capsule-forming) and resistant (capsule-forming) strains. The results suggest that differences in their encapsulation response involve a single gene, resistance to Leptopilina boulardi(Rlb), with two alleles, the resistant one being dominant.Rlb confers specific protection against Leptopilina boulardi and is thus probably involved in parasitoid recognition. Recent studies have localized this gene on the right arm of the second chromosome and our aim was to precisely determine its genetic and molecular location. Using strains bearing deletions, we demonstrated that resistance to Leptopilina boulardi is conferred by the55C; 55F3 region and that the 55E2–E6; F3 region is particularly involved. A physical map of the 55C;56A region was then constructed, based on a set of overlapping cosmid and P1 phage clones. Using single and double digests, cross hybridization of restriction fragments, and location of genetically mapped genes and STSs, a complete, five-enzyme restriction map of this 830-kb region was obtained.

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Mapping candidate genes for Drosophila melanogaster resistance to the parasitoid wasp Leptopilina boulardi

Genetics Research ◽

10.1017/s001667230600841x ◽

2006 ◽

Vol 88 (2) ◽

pp. 81-91 ◽

Cited By ~ 15

Author(s):

M. HITA ◽

E. ESPAGNE ◽

F. LEMEUNIER ◽

L. PASCUAL ◽

Y. CARTON ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Candidate Genes ◽

Resistance Gene ◽

Molecular Level ◽

Single Gene ◽

Parasitoid Wasp ◽

Male Recombination ◽

Leptopilina Boulardi

Drosophila melanogaster resistance against the parasitoid wasp Leptopilina boulardi is under the control of a single gene (Rlb), with two alleles, the resistant one being dominant. Using strains bearing deletions, we previously demonstrated that the 55E2–E6; 55F3 region on chromosome 2R is involved in the resistance phenomenon. In this paper, we first restricted the Rlb containing region by mapping at the molecular level the breakpoints of the Df(2R)Pc66, Df(2R)P34 and Df(2R)Pc4 deficiencies, using both chromosomal in situ hybridization and Southern analyses. The resistance gene was localized in a 100 kb fragment, predicted to contain about 10 different genes. Male recombination genetic experiments were then performed, leading to identification of two possible candidates for the Rlb gene. Potential involvement of one of this genes, edl/mae, is discussed.

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Genetic and Bioinformatic Analysis of 41C and the 2R Heterochromatin of Drosophila melanogaster: A Window on the Heterochromatin-Euchromatin Junction

Genetics ◽

10.1093/genetics/166.2.807 ◽

2004 ◽

Vol 166 (2) ◽

pp. 807-822 ◽

Cited By ~ 1

Author(s):

Steven H Myster ◽

Fei Wang ◽

Robert Cavallo ◽

Whitney Christian ◽

Seema Bhotika ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Large Scale ◽

Physical Map ◽

Chromosome Region ◽

Bioinformatic Analysis ◽

Pericentric Heterochromatin ◽

Genome Project ◽

Essential Genes ◽

Complementation Groups ◽

The Right

Abstract Genomic sequences provide powerful new tools in genetic analysis, making it possible to combine classical genetics with genomics to characterize the genes in a particular chromosome region. These approaches have been applied successfully to the euchromatin, but analysis of the heterochromatin has lagged somewhat behind. We describe a combined genetic and bioinformatics approach to the base of the right arm of the Drosophila melanogaster second chromosome, at the boundary between pericentric heterochromatin and euchromatin. We used resources provided by the genome project to derive a physical map of the region, examine gene density, and estimate the number of potential genes. We also carried out a large-scale genetic screen for lethal mutations in the region. We identified new alleles of the known essential genes and also identified mutations in 21 novel loci. Fourteen complementation groups map proximal to the assembled sequence. We used PCR to map the endpoints of several deficiencies and used the same set of deficiencies to order the essential genes, correlating the genetic and physical map. This allowed us to assign two of the complementation groups to particular “computed/curated genes” (CGs), one of which is Nipped-A, which our evidence suggests encodes Drosophila Tra1/TRRAP.

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Patterns of naturally occurring restriction map variation, dopa decarboxylase activity variation and linkage disequilibrium in the Ddc gene region of Drosophila melanogaster.

Genetics ◽

10.1093/genetics/132.2.443 ◽

1992 ◽

Vol 132 (2) ◽

pp. 443-452 ◽

Cited By ~ 1

Author(s):

C F Aquadro ◽

R M Jennings ◽

M M Bland ◽

C C Laurie ◽

C H Langley

Keyword(s):

Enzyme Activity ◽

Drosophila Melanogaster ◽

Linkage Disequilibrium ◽

Single Gene ◽

Natural Populations ◽

Dopa Decarboxylase ◽

Restriction Map ◽

Decarboxylase Activity ◽

Site Variation ◽

Dense Cluster

Abstract Forty-six second-chromosome lines of Drosophila melanogaster isolated from five natural populations were surveyed for restriction map variation in a 65-kb region surrounding the gene (Ddc) encoding dopa decarboxylase (DDC). Sixty-nine restriction sites were scored, 13 of which were polymorphic. Average heterozygosity per nucleotide was estimated to be 0.005. Eight large (0.7-5.0 kb) inserts, two small inserts (100 and 200 bp) and three small deletions (100-300 bp) were also observed across the 65-kb region. We see no evidence for a reduction in either nucleotide heterozygosity or insertion/deletion variation in the central 26-kb segment containing Ddc and a dense cluster of lethal complementation groups and transcripts (greater than or equal to 9 genes) compared to that seen in the adjacent regions (totaling 39 kb) in which only a single gene and transcript has been detected, or to that observed for other gene regions in D. melanogaster. The distribution of restriction site variation shows no significant departure from that expected under an equilibrium neutral model. However insertions and deletions show a significant departure from neutrality in that they are too rare in frequency, consistent with them being deleterious on average. Significant linkage disequilibrium among variants exists across much of the 65-kb region. Lower regional rates of recombination combined with the influence of polymorphic chromosomal inversions, rather than epistatic selection among genes in the dense cluster, probably are sufficient explanations for the creation and/or maintenance of the linkage disequilibrium observed in the Ddc region. We have also assayed adult DDC enzyme activity in these same lines. Twofold variation in activity among lines is observed within our sample. Significant associations are observed between level of DDC enzyme activity and restriction map variants. Surprisingly, one line with a 5.0-kb insert within an intron and one line with a 1.5-kb insert near the 5' end of Ddc each show normal adult DDC activities.

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CLONING AND PHYSICAL MAPPING OF AN EARLY REGION OF THE BACTERIOPHAGE T4 GENOME

Genetics ◽

10.1093/genetics/106.1.1 ◽

1984 ◽

Vol 106 (1) ◽

pp. 1-16

Author(s):

Paul M Macdonald ◽

Gisela Mosig

Keyword(s):

Physical Mapping ◽

Bacteriophage T4 ◽

Restriction Endonucleases ◽

Restriction Map ◽

Wild Type ◽

End Points ◽

Restriction Fragments ◽

Early Region ◽

Dna Restriction Fragments ◽

Dna Restriction

ABSTRACT We have cloned DNA restriction fragments from the largely nonessential region of bacteriophage T4 located between genes 39 and 56. The cloned DNA fragments were used to construct a precise map of the sites in this region recognized by eight restriction endonucleases. This restriction map allowed us to compare the cytosine-containing T4 DNA used for cloning with the hydroxymethylcytosine-containing DNA of wild-type T4; there were no detectable rearrangements in the region tested. We were also able to determine the physical locations of several deletion end points and of several genes.

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CYTOGENETIC ANALYSIS OF CHROMOSOME 3 IN DROSOPHILA MELANOGASTER: THE HOMOEOTIC GENE COMPLEX IN POLYTENE CHROMOSOME INTERVAL 84A-B

Genetics ◽

10.1093/genetics/94.1.115 ◽

1980 ◽

Vol 94 (1) ◽

pp. 115-133 ◽

Cited By ~ 18

Author(s):

Thomas C Kaufman ◽

Ricki Lewis ◽

Barbara Wakimoto

Keyword(s):

Drosophila Melanogaster ◽

Polytene Chromosome ◽

Cytogenetic Analysis ◽

Proximal Portion ◽

Chromosome 3 ◽

Gene Complex ◽

Anterior Portion ◽

Cytogenetic Evidence ◽

The Right

ABSTRACT Cytogenetic evidence is presented demonstrating that the 84A-B interval in the proximal portion of the right arm of chromosome 3 is the residence of a homoeotic gene complex similar to the bithorax locus. This complex, originally defined by the Antennapedia (A n t p) mutation, controls segmentation in the anterior portion of the organism. Different lesions within this complex homoeotically transform portions OI the prothorax, proboscis, antenna and eye and present clear analogies to similar lesions within the bithorax locus.

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A NOTE ON THE MATERNAL EFFECT MUTANTS DAUGHTERLESS AND ABNORMAL OOCYTE IN DROSOPHILA MELANOGASTER

Genetics ◽

10.1093/genetics/73.1.73 ◽

1973 ◽

Vol 73 (1) ◽

pp. 73-86

Author(s):

Arthur P Mange ◽

L Sandler

Keyword(s):

Drosophila Melanogaster ◽

Maternal Effect ◽

Sex Chromosome ◽

Chromosome 2 ◽

Dominant Marker ◽

Enhancing Effect ◽

X Irradiation ◽

The Right ◽

Chromosome Breakpoint ◽

Special Region

ABSTRACT Two deficiencies for, and a dominant enhancer of, the second chromosome maternal effect mutant, "daughterless" (da), were induced with X-irradiation. Their properties were studied with respect to both da and the linked maternal effect mutant, "abnormal oocyte" (abo), with the following conclusions. (1) The most probable map positions of da and abo are: J–½–da–2½–abo, where J is a dominant marker located at 41 on the standard map. (2) The da locus is in bands 31CD-F on the polytene chromosome map; abo is to the right of 32A. (3) Because homozygous da individuals survive while individuals carrying da and a deficiency for da are lethal, it is concluded that da is hypomorphic. (4) From a weak da-like maternal effect in heterozygous da females induced by an "Enhancer of da," we have confirmed a previous report that (a) the amount of sex chromosome heterochromatin contributed by the father can influence the severity of the da maternal effect, and (b) the sex chromosome heterochromatin which influences the da effect is different from that which influences the abo effect. (5) The possibility that da and abo are in a special region of chromosome 2 concerned with the regulation of sex chromosome heterochromatin is strengthened by the observation that the Enhancer of da appears to rescue abnormal eggs produced by homozygous abo mothers. (6) The Enhancer of da is a translocation between chromosomes 2 and 3 with the second chromosome breakpoint in the basal heterochromatin; because the enhancing effect maps in this region of chromosome 2, it is possible that autosomal, as well as sex chromosomal, heterochromatin interacts with da and abo.

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Comparative physical mapping reveals features of microsynteny between Glycine max, Medicago truncatula, and Arabidopsis thaliana

Genome ◽

10.1139/g03-106 ◽

2004 ◽

Vol 47 (1) ◽

pp. 141-155 ◽

Cited By ~ 38

Author(s):

H H Yan ◽

J Mudge ◽

D-J Kim ◽

R C Shoemaker ◽

D R Cook ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Glycine Max ◽

Medicago Truncatula ◽

Physical Mapping ◽

Large Scale ◽

Sequence Similarity ◽

Artificial Chromosome ◽

Bac Contig ◽

Cross Hybridization ◽

Bac Contigs

To gain insight into genomic relationships between soybean (Glycine max) and Medicago truncatula, eight groups of bacterial artificial chromosome (BAC) contigs, together spanning 2.60 million base pairs (Mb) in G. max and 1.56 Mb in M. truncatula, were compared through high-resolution physical mapping combined with sequence and hybridization analysis of low-copy BAC ends. Cross-hybridization among G. max and M. truncatula contigs uncovered microsynteny in six of the contig groups and extensive microsynteny in three. Between G. max homoeologous (within genome duplicate) contigs, 85% of coding and 75% of noncoding sequences were conserved at the level of cross-hybridization. By contrast, only 29% of sequences were conserved between G. max and M. truncatula, and some kilobase-scale rearrangements were also observed. Detailed restriction maps were constructed for 11 contigs from the three highly microsyntenic groups, and these maps suggested that sequence order was highly conserved between G. max duplicates and generally conserved between G. max and M. truncatula. One instance of homoeologous BAC contigs in M. truncatula was also observed and examined in detail. A sequence similarity search against the Arabidopsis thaliana genome sequence identified up to three microsyntenic regions in A. thaliana for each of two of the legume BAC contig groups. Together, these results confirm previous predictions of one recent genome-wide duplication in G. max and suggest that M. truncatula also experienced ancient large-scale genome duplications.Key words: Glycine max, Medicago truncatula, Arabidopsis thaliana, conserved microsynteny, genome duplication.

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Genetics of Differences in Pheromonal Hydrocarbons Between Drosophila melanogaster and D. simulans

Genetics ◽

10.1093/genetics/143.1.353 ◽

1996 ◽

Vol 143 (1) ◽

pp. 353-364 ◽

Cited By ~ 3

Author(s):

Jerry A Coyne

Keyword(s):

Drosophila Melanogaster ◽

Sexual Dimorphism ◽

Genetic Analysis ◽

Species Difference ◽

The Other ◽

Chromosome 3 ◽

Apparent Effect ◽

The Third ◽

Hydrocarbon Profile ◽

The Right

Abstract Females of Drosophila melanogaster and its sibling species D. simulans have very different cuticular hydrocarbons, with the former bearing predominantly 7,11-heptacosadiene and the latter 7-tricosene. This difference contributes to reproductive isolation between the species. Genetic analysis shows that this difference maps to only the third chromosome, with the other three chromosomes having no apparent effect. The D. simulans alleles on the left arm of chromosome 3 are largely recessive, allowing us to search for the relevant regions using D. melanogaster deficiencies. At least four nonoverlapping regions of this arm have large effects on the hydrocarbon profile, implying that several genes on this arm are responsible for the species difference. Because the right arm of chromosome 3 also affects the hydrocarbon profile, a minimum of five genes appear to be involved. The large effect of the third chromosome on hydrocarbons has also been reported in the hybridization between D. simulans and its closer relative D. sechellia, implying either an evolutionaly convergence or the retention in D. sechllia of an ancestral sexual dimorphism.

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A cDNA from Drosophila melanogaster encodes a lamin C-like intermediate filament protein

Journal of Cell Science ◽

10.1242/jcs.104.4.1263 ◽

1993 ◽

Vol 104 (4) ◽

pp. 1263-1272 ◽

Cited By ~ 4

Author(s):

C.A. Bossie ◽

M.M. Sanders

Keyword(s):

Drosophila Melanogaster ◽

Intermediate Filament ◽

Blot Analysis ◽

Polytene Chromosomes ◽

Intermediate Filament Protein ◽

Chromosome 2 ◽

Cross Hybridization ◽

Intermediate Filament Proteins ◽

Nuclear Lamins ◽

Filament Protein

A novel intermediate filament cDNA, pG-IF, has been isolated from a Drosophila melanogaster embryonic expression library screened with a polyclonal antiserum produced against a 46 kDa cytoskeletal protein isolated from Kc cells. This 46 kDa protein is known to be immunologically related to vertebrate intermediate filament proteins. The screen resulted in the isolation of four different cDNA groups. Of these, one has been identified as the previously characterized Drosophila nuclear lamin cDNA, Dm0, and a second, pG-IF, demonstrates homology to Dm0 by cross hybridization on Southern blots. DNA sequence analysis reveals that pG-IF encodes a newly identified intermediate filament protein in Drosophila. Its nucleotide sequence is highly homologous to nuclear lamins with lower homology to cytoplasmic intermediate filament proteins. pG-IF predicts a protein of 621 amino acids with a predicted molecular mass of 69,855 daltons. In vitro transcription and translation of pG-IF yielded a protein with a SDS-PAGE estimated molecular weight of approximately 70 kDa. It contains sequence principles characteristic of class V intermediate filament proteins. Its near neutral pI (6.83) and the lack of a terminal CaaX motif suggests that it may represent a lamin C subtype in Drosophila. In situ hybridization to polytene chromosomes detects one band of hybridization on the right arm of chromosome 2 at or near 51A. This in conjunction with Southern blot analysis of various genomic digests suggests one or more closely placed genes while Northern blot analysis detects two messages in Kc cells.

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