The recent invasion of natural Drosophila simulans populations by the P-element

The P-element is one of the best understood eukaryotic transposable elements. It invaded Drosophila melanogaster populations within a few decades but was thought to be absent from close relatives, including Drosophila simulans. Five decades after the spread in D. melanogaster, we provide evidence that the P-element has also invaded D. simulans. P-elements in D. simulans appear to have been acquired recently from D. melanogaster probably via a single horizontal transfer event. Expression data indicate that the P-element is processed in the germ line of D. simulans, and genomic data show an enrichment of P-element insertions in putative origins of replication, similar to that seen in D. melanogaster. This ongoing spread of the P-element in natural populations provides a unique opportunity to understand the dynamics of transposable element spread and the associated piwi-interacting RNAs defense mechanisms.

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The P-element strikes again: the recent invasion of naturalDrosophila simulanspopulations

10.1101/013722 ◽

2015 ◽

Cited By ~ 2

Author(s):

Robert Kofler ◽

Tom Hill ◽

Viola Nolte ◽

Andrea Betancourt ◽

Christian Schlötterer

Keyword(s):

Drosophila Melanogaster ◽

Defense Mechanisms ◽

Natural Populations ◽

Genomic Data ◽

P Element ◽

Expression Data ◽

Transfer Event ◽

P Elements ◽

Origins Of Replication ◽

Close Relatives

The P-element is one of the best understood eukaryotic transposable elements. It invadedDrosophila melanogasterpopulations within a few decades, but was thought to be absent from close relatives, includingD. simulans. Five decades after the spread inD. melanogaster, we provide evidence that the P-element has also invadedD. simulans. P-elements inD. simulansappear to have been acquired recently fromD. melanogasterprobably via a single horizontal transfer event. Expression data indicate that the P-element is processed in the germline ofD. simulans, and genomic data show an enrichment of P-element insertions in putative origins of replication, similar to that seen inD. melanogaster. This ongoing spread of the P-element in natural populations provides an unique opportunity to understand the dynamics of transposable element spreads and the associated piRNA defense mechanisms.

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Evidence for horizontal transmission of the P transposable element between Drosophila species.

Genetics ◽

10.1093/genetics/124.2.339 ◽

1990 ◽

Vol 124 (2) ◽

pp. 339-355 ◽

Cited By ~ 12

Author(s):

S B Daniels ◽

K R Peterson ◽

L D Strausbaugh ◽

M G Kidwell ◽

A Chovnick

Keyword(s):

Horizontal Transfer ◽

Horizontal Transmission ◽

Natural Populations ◽

P Element ◽

Base Substitution ◽

Potential Donor ◽

Transfer Event ◽

P Elements ◽

Autonomous Element ◽

Group A

Abstract Several studies have suggested that P elements have rapidly spread through natural populations of Drosophila melanogaster within the last four decades. This observation, together with the observation that P elements are absent in the other species of the melanogaster subgroup, has lead to the suggestion that P elements may have entered the D. melanogaster genome by horizontal transmission from some more distantly related species. In an effort to identify the potential donor in the horizontal transfer event, we have undertaken an extensive survey of the genus Drosophila using Southern blot analysis. The results showed that P-homologous sequences are essentially confined to the subgenus Sophophora. The strongest P hybridization occurs in species from the closely related willistoni group. A wild-derived strain of D. willistoni was subsequently selected for a more comprehensive molecular examination. As part of the analysis, a complete P element was cloned and sequenced from this line. Its nucleotide sequence was found to be identical to the D. melanogaster canonical P, with the exception of a single base substitution at position 32. When the cloned element was injected into D. melanogaster embryos, it was able to both promote transposition of a coinjected marked transposon and induce singed-weak mutability, thus demonstrating its ability to function as an autonomous element. The results of this study suggest that D. willistoni may have served as the donor species in the horizontal transfer of P elements to D. melanogaster.

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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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P transposons controlled by the heat shock promoter.

Molecular and Cellular Biology ◽

10.1128/mcb.6.5.1640 ◽

1986 ◽

Vol 6 (5) ◽

pp. 1640-1649 ◽

Cited By ~ 50

Author(s):

H Steller ◽

V Pirrotta

Keyword(s):

Heat Shock ◽

Germ Line ◽

Fusion Gene ◽

P Element ◽

Translational Efficiency ◽

Heat Shock Promoter ◽

P Elements ◽

Heat Shocks ◽

Neomycin Resistance ◽

Heat Shock Induction

We have transformed Drosophila melanogaster with modified P-element transposons, which express the transposase function from the heat-inducible hsp70 heat shock promoter. The Icarus transposon, which contains a direct hsp70-P fusion gene, behaved like a very active autonomous P element even before heat shock induction. Although heat shock led to abundant somatic transcription, transposition of the Icarus element was confined to germ line cells. To reduce the constitutive transposase activity observed for the Icarus element, we attenuated the translational efficiency of the transposase RNA by inserting the transposon 5 neomycin resistance gene between the hsp70 promoter and the P-element sequences. The resulting construct, called Icarus-neo, conferred resistance to G418, and its transposition was significantly stimulated by heat shock. Heat shocks applied during the embryonic or third instar larval stage had similar effects, indicating that transposition of P elements is not restricted to a certain developmental stage. Both Icarus and Icarus-neo destabilized snw in a P-cytotype background and thus at least partially overcome the repression of transposition. Our results suggest that the regulation of P-element transposition occurs at both the transcriptional and posttranscriptional levels.

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Accumulation of P elements in minority inversions in natural populations of Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672300030111 ◽

1992 ◽

Vol 59 (1) ◽

pp. 1-9 ◽

Cited By ~ 27

Author(s):

Walter F. Eanes ◽

Cedric Wesley ◽

Brian Charlesworth

Keyword(s):

Mathematical Model ◽

Drosophila Melanogaster ◽

Copy Number ◽

Natural Populations ◽

P Element ◽

P Elements ◽

Chromosomal Inversions ◽

Associated Production ◽

African Populations ◽

Parameter Values

SummaryThe accumulation of a transposable element inside chromosomal inversions is examined theoretically by a mathematical model, and empirically by counts of P elements associated with inversion polymorphisms in natural populations of Drosophila melanogaster. The model demonstrates that, if heterozygosity for an inversion effectively reduces element associated production of detrimental chromosome rearrangements, a differential accumulation of elements is expected, with increased copy number inside the minority inversion. Several-fold differential accumulations are possible with certain parameter values. We present data on P element counts for inversion polymorphisms on all five chromosome arms of 157 haploid genomes from two African populations. Our observations show significantly increased numbers of elements within the regions associated with the least common, or minority arrangements, in natural inversion polymorphisms.

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Germ-line and somatic recombination induced by in vitro modified P elements in Drosophila melanogaster.

Genetics ◽

10.1093/genetics/124.2.331 ◽

1990 ◽

Vol 124 (2) ◽

pp. 331-337 ◽

Cited By ~ 2

Author(s):

J A Sved ◽

W B Eggleston ◽

W R Engels

Keyword(s):

Drosophila Melanogaster ◽

Germ Line ◽

Somatic Cells ◽

Chromosome Breakage ◽

P Element ◽

Male Germ Line ◽

Male Recombination ◽

P Elements ◽

Somatic Recombination

Abstract The P element insertion delta 2-3(99B) has previously been shown to activate incomplete P elements elsewhere in the genome. We show that this element, in conjunction with a second incomplete P element, P[CaSpeR], also induces recombination in the male germ line. The recombination is induced preferentially in the region of the P[CaSpeR] element. Recombinant chromosomes contain the P[CaSpeR] element in more than 50% of cases, and alternative models of transposon replication and preferential chromosome breakage are put forward to explain this finding. As is the case with male recombination induced by P-M dysgenic crosses, recombination appears to be premeiotic in a high proportion of cases. The delta 2-3(99B) element is known to act in somatic cells. Correspondingly, we show that the delta 2-3(99B)-P[CaSpeR] combination elevates the incidence of somatic recombination.

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Transposable element-induced fitness mutations in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672300024794 ◽

1986 ◽

Vol 48 (2) ◽

pp. 77-87 ◽

Cited By ~ 50

Author(s):

Trudy F. C. Mackay

Keyword(s):

Drosophila Melanogaster ◽

Extraction Procedure ◽

Natural Populations ◽

P Element ◽

Recessive Lethal ◽

P Elements ◽

Fitness Traits ◽

Mutational Effect ◽

Evolution Of Transposable Elements ◽

Mutational Variance

SummaryP element mutagenesis was used to contaminate M strain second chromosomes with P elements. The contaminated lines were compared to uncontaminated control lines for homozygous and heterozygous fitness and its components. Mean homozygous fitness, viability and fertility of chromosome lines contaminated with P elements is decreased relative to the uncontaminated control lines by, respectively, 55, 28 and 40%. Variance among contaminated homozygous lines of total fitness increases by a factor of 1·5, variance of viability by a factor of 5·9, and variance of fertility by a factor of 1·9, compared to variance of these traits among the population of uncontaminated homozygous chromosomes. Estimates of P-element-induced mutational variance among second chromosome lines for homozygous fitness, viability and fertility are, respectively, 2 × 10−2, 5 × 10−2 and 2 × 10−2. This magnitude of mutational effect is equivalent, in terms of incidence of induced recessive lethal chromosomes and D:L ratio, to a dose of approximately 1·0–2·5 × 10−3 m EMS. The distributions of fitness traits among M-derived second chromosome homozygous lines contaminated with P elements are remarkably similar in many regards to distributions of fitness and viability of chromosomal homozygotes derived from natural Drosophila populations. It is possible that a proportion of the fitness variation previously observed (reviewed by Simmons & Crow, 1977) following homozygosis of wild chromosomes was not present in the natural populations, but was generated by P-element transposition during the chromosome extraction procedure. P-element-induced fitness mutations appear to be completely recessive. Implications for models of evolution of transposable elements are discussed.

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The Influence of Nonautonomous P Elements on Hybrid Dysgenesis in Drosophila melanogaster

Genetics ◽

10.1093/genetics/117.4.671 ◽

1987 ◽

Vol 117 (4) ◽

pp. 671-685

Author(s):

Michael J Simmons ◽

John D Raymond ◽

Michael J Boedigheimer ◽

Joseph R Zunt

Keyword(s):

Germ Line ◽

Hybrid Dysgenesis ◽

P Element ◽

Insertion Mutation ◽

Distorted Segregation ◽

P Elements ◽

Segregation Ratios ◽

Two Generations ◽

Element Activity ◽

Kinetics Of

ABSTRACT An inbred line of the M' strain Muller-5 Birmingham was studied for its abilities to affect P-M hybrid dysgenesis. This strain possesses 57 P elements, all of which are apparently defective in the production of the P transposase. In combination with transposase-producing elements, these nonautonomous elements can enhance or diminish the incidence of hybrid dysgenesis, depending on the trait that is studied. Dysgenic flies that have one or more paternally-derived chromosomes with these elements partially repress the instability of the P element insertion mutation, snw; however, such flies have elevated frequencies of another dysgenic trait, GD sterility, and also show distorted segregation ratios. An explanation is presented in which all of these phenomena are unified as manifestations of the kinetics of P element activation in the germ line. The progeny of Muller-5 Birmingham females exhibit partial repression of both snw instability and GD sterility. This repression appears to involve a factor that can be transmitted maternally through at least two generations. This mode of repression therefore conforms to the pattern of inheritance of the P cytotype, the condition that brings about nearly total repression of P element activity in some strains. Models in which this repression could arise from the nonautonomous P elements of Muller-5 Birmingham are discussed.

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Disgenesia do híbrido em populações naturais de Drosophila melanogaster.

Ciência e Natura ◽

10.5902/2179460x27019 ◽

1999 ◽

Vol 21 (21) ◽

pp. 51 ◽

Cited By ~ 1

Author(s):

Chirlei Cintia Klein ◽

Liliana Essi ◽

Ronaldo Medeiros Golombieski ◽

Élgion Lúcio da Silva Loreto

Keyword(s):

Drosophila Melanogaster ◽

Molecular Analysis ◽

Natural Populations ◽

Rio Grande ◽

P Element ◽

Rio Grande Do Sul ◽

Genetic Traits ◽

P Elements ◽

Regulatory Capacity ◽

Element Activity

Hybrid dysgenesis has been defined as a remarkable syndrome of correlated genetic traits that are produced in some particular crosses between certain strains. The present study main objective was classify recently collected Drosophila melanogaster strains in relation to P element activity and regulatory capacity. Our results to natural populations trapped from Rio Grande do Sul, Brazil and Colombia shows that it fell on Q class, since all examinated strains has showed P elements by molecular analysis and low P activity. In the same way, these strains shows low susceptibility to P element action. The bigger values found in the colombian population are in agreement with the clinal hypothesis to P element activity.

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