hobo enhancer trapping mutagenesis in Drosophila reveals an insertion specificity different from P elements.

Abstract P element enhancer trapping has become an indispensable tool in the analysis of the Drosophila melanogaster genome. However, there is great variation in the mutability of loci by these elements such that some loci are relatively refractory to insertion. We have developed the hobo transposable element for use in enhancer trapping and we describe the results of a hobo enhancer trap screen. In addition, we present evidence that a hobo enhancer trap element has a pattern of insertion into the genome that is different from the distribution of P elements in the available database. Hence, hobo insertion may facilitate access to genes resistant to P element insertion.

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A particular P-element insertion is correlated to the P-induced hybrid dysgenesis repression in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672300030627 ◽

1992 ◽

Vol 60 (1) ◽

pp. 15-24 ◽

Cited By ~ 5

Author(s):

Dominique Higuet ◽

Dominique Anxolabéhére ◽

Danielle Nouaud

Keyword(s):

Drosophila Melanogaster ◽

Promoter Activity ◽

Hybrid Dysgenesis ◽

P Element ◽

P Elements ◽

Element Insertion ◽

Element Number

SummaryTransposable P elements in Drosophila melanogaster cause hybrid dysgenesis if their mobility is not repressed. The ability to regulate the dysgenic activity of the P elements depends on several mechanisms, one of which hypothesized that a particular deleted P element (the KP element) results in a non-susceptibility which is biparentally transmitted. In this study totally nonsusceptible lines, and susceptible lines containing exclusively KP elements (IINS2 line and IIS2 line) were isolated from a M' strain. We show that non-susceptibility is correlated with a particular insertion of one KP element located at the cytological site 47D1. The repression ability of the GD sterility is determined by a recessive chromosomal factor, and cannot be due to the KP-element number. Here the repression of the P mobility is associated with reduction of the P transcripts and the inhibition of P promoter activity.

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Molecular analysis of the P-M gonadal dysgenesis cline in eastern Australian Drosophila melanogaster.

Genetics ◽

10.1093/genetics/119.4.889 ◽

1988 ◽

Vol 119 (4) ◽

pp. 889-902

Author(s):

I A Boussy ◽

M J Healy ◽

J G Oakeshott ◽

M G Kidwell

Keyword(s):

Drosophila Melanogaster ◽

Transposable Element ◽

Gonadal Dysgenesis ◽

Molecular Techniques ◽

P Element ◽

Latitudinal Cline ◽

Deletion Derivative ◽

P Elements ◽

Regulatory Ability ◽

Eastern Australia

Abstract The latitudinal cline in P-M gonadal dysgenesis potential in eastern Australia has been shown to comprise three regions which are, from north to south respectively, P, Q, and M, with the P-to-Q and Q-to-M transitions occurring over relatively short distances. The P element complements of 30 lines from different regions of the cline were determined by molecular techniques. The total amount of P element-hybridizing DNA was high in all lines, and it did not correlate in any obvious way with the P-M phenotypes of individual lines. The number of potentially full-sized P elements per genome was high in lines from the P regions, but variable or low among lines from the Q and M regions, and thus declined overall from north to south. A particular P element deletion-derivative, the KP element, occurred in all the tested lines. The number of KP elements was low in lines from the P region, much higher in lines from the Q region, and highest among lines from the M region, thus forming a cline reciprocal to that of the full-sized P elements. Another transposable element, hobo, which has been described as causing dysgenic traits similar to those of P-M hybrid dysgenesis, was shown to be present in all lines and to vary among them in number, but not in any latitudinal pattern. The P-M cline in gonadal dysgenesis potential can be inferred to be based on underlying clinal patterns of genomic P element complements. P activity of a line was positively correlated with the number of full-sized P elements in the line, and negatively correlated with the number of KP elements. Among Q and M lines, regulatory ability was not correlated with numbers of KP elements.

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Transposable element-induced polygenic mutations in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672300027117 ◽

1987 ◽

Vol 49 (3) ◽

pp. 225-233 ◽

Cited By ~ 19

Author(s):

Trudy F. C. Mackay

Keyword(s):

Drosophila Melanogaster ◽

Transposable Element ◽

Quantitative Traits ◽

Natural Populations ◽

P Element ◽

Environmental Variance ◽

X Ray ◽

P Elements ◽

Very High ◽

Mutational Variance

SummaryP-element mutagenesis was used to contaminate M-strain second chromosomes with P elements. The effect of P-element transposition on abdominal and sternopleural bristle scores and on female productivity was deduced by comparing the distributions of these quantitative traits among the contaminated second-chromosome lines with a control population of M-strain second-chromosome lines free of P elements. Estimates of P-element-induced mutational variance, Vm, for these characters are very high, and mutational ‘heritabilities’ (Vm/Ve, the ratio of mutational variance to environmental variance) are of the same order as heritabilities of these traits from natural populations. P-element-induced mutational variance of abdominal bristle score is roughly two orders of magnitude greater than spontaneous and X-ray-induced Vm/Ve for this trait.

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Rapid spread of a P element/Adh gene construct through experimental populations of Drosophila melanogaster

Genome ◽

10.1139/g93-155 ◽

1993 ◽

Vol 36 (6) ◽

pp. 1169-1175 ◽

Cited By ~ 14

Author(s):

G. A. Meister ◽

T. A. Grigliatti

Keyword(s):

Drosophila Melanogaster ◽

Alcohol Dehydrogenase ◽

Transposable Elements ◽

Transposable Element ◽

Dehydrogenase Activity ◽

P Element ◽

P Elements ◽

Alcohol Dehydrogenase Activity ◽

Adh Gene ◽

Experimental Populations

Transposable elements may be potential tools for the dispersal of engineered DNA through target insect populations. The utility of this hypothesis is predicated on the ability of transposable elements carrying a large DNA insert to rapidly disperse through a population. In addition, the inserted DNA must be replicated with a high degree of fidelity during this dispersal. We have monitored the ability of a transposable element with an inserted gene to spread through experimental populations and tested whether the passenger gene retains its ability to encode an active protein. Several Drosophila melanogaster laboratory populations were initiated with female flies that were null for alcohol dehydrogenase activity and contained no P elements. Most of the females were mated to males of the same strain; however, 1 or 10% of the females were mated to males from a strain that had previously been transformed with a helper P element and a P element/Adh gene construct. The dispersal of P elements to new genomes was monitored at each generation by randomly selecting females and performing DNA hybridization assays on dissected ovarian tissue. In addition, each female was tested for alcohol dehydrogenase activity using a simple histochemical assay. We find that, despite an approximate threefold increase in size, the P element constructs containing a functioning gene are still capable of rapid dispersal through the experimental populations. We also show that many of the inserted Adh genes still encode an active product.Key words: P element, transformation, Adh, transposable element.

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Somatic reversion of P transposable element insertion mutations in the singed locus of Drosophila melanogaster requiring specific P insertions and a trans- acting factor

Genetics Research ◽

10.1017/s0016672300028470 ◽

1989 ◽

Vol 54 (2) ◽

pp. 101-112 ◽

Cited By ~ 3

Author(s):

John F. Y. Brookfield ◽

Alan P. Lewis

Keyword(s):

Drosophila Melanogaster ◽

Transposable Element ◽

Maternal Effect ◽

P Element ◽

Chromosome 2 ◽

Restriction Maps ◽

Element Insertion ◽

Somatic Reversion ◽

P Transposable Element ◽

Insertion Mutations

SummaryDestabilization in somatic cells of P-element insertions in the X-linked singed gene of Drosophila melanogaster has been studied. We have shown that some but not all unstable P-element insertions in singed can form mosaics. The cause of this variation is not clear from studies of the restriction maps of the mutations tested. The transposable element movements occur early in development and require, in addition to an appropriate P-element insertion in singed, a trans-acting maternal effect component. Movements appear to occur preferentially in attached-X stocks. However, the maternal effect component maps to the central region of chromosome 2.

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Molecular analysis of an unstable P element insertion at the singed locus of Drosophila melanogaster: evidence for intracistronic transposition of a P element.

Genetics ◽

10.1093/genetics/119.1.85 ◽

1988 ◽

Vol 119 (1) ◽

pp. 85-94

Author(s):

R S Hawley ◽

R A Steuber ◽

C H Marcus ◽

R Sohn ◽

D M Baronas ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Detailed Analysis ◽

Chromosome Aberration ◽

Sister Chromatid ◽

High Frequency ◽

P Element ◽

Wild Type ◽

P Elements ◽

Element Insertion ◽

Inverted Orientation

Abstract In a companion study, a number of P element insertions into the singed locus were characterized. Here is reported a detailed analysis of the structure and mutability of another P element insertion at sn, known as sncm. Under conditions which mobilize P elements, sncm mutates at high frequency to both wild-type (sn+) and to a much more extreme allele (snext). Wild-type revertants appear to represent precise or nearly precise excisions of the P element. Certainly two, and most likely all five, of the snext alleles studied result from the insertion of a duplicate copy of this P element into a nearby site in an inverted orientation. We propose a model in which both the sn+ and snext mutational events can be explained by excision of the P element from one chromatid followed by reintegration into the sister chromatid at a nearby site (intracistronic transposition). Finally, it is shown that the snext alleles are themselves unstable and the structure of a resulting chromosome aberration is examined.

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P-Element Insertion Alleles of Essential Genes on the Third Chromosome of Drosophila melanogaster Correlation of Physical and Cytogenetic Maps in Chromosomal Region 86E-87F

Genetics ◽

10.1093/genetics/147.4.1697 ◽

1997 ◽

Vol 147 (4) ◽

pp. 1697-1722 ◽

Cited By ~ 1

Author(s):

Peter Deák ◽

Mahmoud M Omar ◽

Robert D C Saunders ◽

Margit Pál ◽

Orbán Komonyi ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Genetic Maps ◽

P Element ◽

Drosophila Genome ◽

Induced Mutations ◽

Lethal Mutant ◽

P Elements ◽

Element Insertion ◽

The Third ◽

Complementation Groups

Abstract We have established a collection of 2460 lethal or semi-lethal mutant lines using a procedure thought to insert single P elements into vital genes on the third chromosome of Drosophila melanogaster. More than 1200 randomly selected lines were examined by in situ hybridization and 90% found to contain single insertions at sites that mark 89% of all lettered subdivisions of the Bridges' map. A set of chromosomal deficiencies that collectively uncover ~25% of the euchromatin of chromosome 3 reveal lethal mutations in 468 lines corresponding to 145 complementation groups. We undertook a detailed analysis of the cytogenetic interval 86E-87F and identified 87 P-element-induced mutations falling into 38 complementation groups, 16 of which correspond to previously known genes. Twenty-one of these 38 complementation groups have at least one allele that has a P-element insertion at a position consistent with the cytogenetics of the locus. We have rescued P elements and flanking chromosomal sequences from the 86E-87F region in 35 lines with either lethal or genetically silent P insertions, and used these as probes to identify cosmids and P1 clones from the Drosophila genome projects. This has tied together the physical and genetic maps and has linked 44 previously identified cosmid contigs into seven “super-contigs” that span the interval. STS data for sequences flanking one side of the P-element insertions in 49 lines has identified insertions in the αγ element at 87C, two known transposable elements, and the open reading frames of seven putative single copy genes. These correspond to five known genes in this interval, and two genes identified by the homology of their predicted products to known proteins from other organisms.

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A hobo Transgene That Encodes the P-Element Transposase in Drosophila melanogaster: Autoregulation and Cytotype Control of Transposase Activity

Genetics ◽

10.1093/genetics/161.1.195 ◽

2002 ◽

Vol 161 (1) ◽

pp. 195-204 ◽

Cited By ~ 1

Author(s):

Michael J Simmons ◽

Kevin J Haley ◽

Craig D Grimes ◽

John D Raymond ◽

Jarad B Niemi

Keyword(s):

Drosophila Melanogaster ◽

Gonadal Dysgenesis ◽

P Element ◽

Hsp70 Gene ◽

Alternate Splicing ◽

Male And Female ◽

P Elements ◽

Male Germline ◽

Female Germline ◽

Transposase Expression

Abstract Drosophila were genetically transformed with a hobo transgene that contains a terminally truncated but otherwise complete P element fused to the promoter from the Drosophila hsp70 gene. Insertions of this H(hsp/CP) transgene on either of the major autosomes produced the P transposase in both the male and female germlines, but not in the soma. Heat-shock treatments significantly increased transposase activity in the female germline; in the male germline, these treatments had little effect. The transposase activity of two insertions of the H(hsp/CP) transgene was not significantly greater than their separate activities, and one insertion of this transgene reduced the transposase activity of P(ry+, Δ2-3)99B, a stable P transgene, in the germline as well as in the soma. These observations suggest that, through alternate splicing, the H(hsp/CP) transgene produces a repressor that feeds back negatively to regulate transposase expression or function in both the somatic and germline tissues. The H(hsp/CP) transgenes are able to induce gonadal dysgenesis when the transposase they encode has P-element targets to attack. However, this ability and the ability to induce P-element excisions are repressed by the P cytotype, a chromosomal/cytoplasmic state that regulates P elements in the germline.

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The Regulatory Properties of Autonomous Subtelomeric P Elements Are Sensitive to a Suppressor of variegation in Drosophila melanogaster

Genetics ◽

10.1093/genetics/143.4.1663 ◽

1996 ◽

Vol 143 (4) ◽

pp. 1663-1674 ◽

Cited By ~ 3

Author(s):

Stéphane Ronsseray ◽

Monique Lehmann ◽

Danielle Nouaud ◽

Dominique Anxolabéhère

Keyword(s):

Drosophila Melanogaster ◽

Genetic Recombination ◽

Natural Populations ◽

P Element ◽

Single Element ◽

Heterochromatin Protein 1 ◽

X Chromosomes ◽

P Elements ◽

Associated Sequences ◽

Regulatory Properties

Abstract Genetic recombination was used in Drosophila melanogaster to isolate P elements, inserted at the telomeres of X chromosomes (cytological site 1A) from natural populations, in a genetic background devoid of other P elements. We show that complete maternally inherited P repression in the germline (P cytotype) can be elicited by only two autonomous P elements at 1A and that a single element at this site has partial regulatory properties. The analysis of the surrounding chromosomal regions of the P elements at 1A shows that in all cases these elements are flanked by Telomeric Associated Sequences, tandemly repetitive noncoding sequences that have properties of heterochromatin. In addition, we show that the regulatory properties of P elements at 1A can be inhibited by some of the mutant alleles of the Su(var)205 gene and by a deficiency of this gene. However, the regulatory properties of reference P strains (Harwich and Texas 007) are not impaired by Su(var)205 mutations. Su(var)205 encodes Heterochromatin Protein 1 (HP1). These results suggest that the HP1 dosage effect on the P element properties is sitedependent and could involve the structure of the chromatin.

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A novel repressor of P element transposition in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672397003066 ◽

1998 ◽

Vol 71 (1) ◽

pp. 21-30 ◽

Cited By ~ 4

Author(s):

RICHARD M. BADGE ◽

JOHN F. Y. BROOKFIELD

Keyword(s):

Drosophila Melanogaster ◽

Inbred Line ◽

Gonadal Dysgenesis ◽

Full Length ◽

P Element ◽

Temperature Dependent ◽

P Elements

We have discovered, in an inbred line (Loua) of Drosophila melanogaster from Zaïre, a third chromosome showing unusual P element repression. Repression of P element transposition by this chromosome, named Loua3, is dominant zygotic and has three unusual properties. Firstly, its repression of the gonadal dysgenesis caused by a strong P haplotype is strongly temperature-dependent, being most evident at higher rearing temperatures. Secondly, subdivision of Loua3 by recombination abolishes repression: the effect is apparently a function of the intact chromosome. Finally, Loua3 also diminishes somatic lethality when chromosomes carrying many ‘ammunition’ elements (Birmingham2) are exposed to the constitutive transposase source Δ2-3(99B). The chromosome has 17 P elements, none full-length, located in at least 12 dispersed positions.

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