Comparative study of P element activity in two natural populations of Drosophila melanogaster.

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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Hybrid dysgenesis in Drosophila melanogaster: the elimination of P elements through repeated backcrossing to an M-type strain

Genome ◽

10.1139/g87-033 ◽

1987 ◽

Vol 29 (1) ◽

pp. 195-200 ◽

Cited By ~ 2

Author(s):

Allen G. Good ◽

Donal A. Hickey

Keyword(s):

Drosophila Melanogaster ◽

Dna Hybridization ◽

Copy Number ◽

Natural Populations ◽

Hybrid Dysgenesis ◽

P Element ◽

P Elements ◽

Element Activity ◽

Equivalent Reduction ◽

Replicative Transposition

The rapid increase in the frequency of P elements in natural populations of Drosophila melanogaster has led to the suggestion that these elements can spread in nature through replicative transposition. In an attempt to model the introduction of a small number of P flies into an M population we backcrossed P flies and their offspring to M flies. Two components of dysgenesis, P element activity and P element copy number (measured by DNA hybridization), were monitored each generation. In these experiments P elements were not capable of spreading rapidly enough to maintain 30–50 copies per fly and were rapidly lost from the population. We also found that the reduction in a fly's ability to induce gonadal dysgenesis was matched by an equivalent reduction in P element copy number as measured by DNA hybridization. These results are discussed in terms of the conventional mechanisms of selection or segregation; the conclusion is that there are conditions under which P elements can be lost from a population. Key words: hybrid dysgenesis, P element, transposable elements, Drosophila.

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Hybrid dysgenesis in natural populations of Drosophila melanogaster in Japan. II. Strains which cannot induce P-M dysgenesis may completely suppress functional P element activity

Genetics Research ◽

10.1017/s0016672300023508 ◽

1987 ◽

Vol 50 (2) ◽

pp. 105-111 ◽

Cited By ~ 2

Author(s):

Nobuko Hagiwara ◽

Etsuko Nakamura ◽

Etsuko T. Matsuura ◽

Sadao I. Chigusa

Keyword(s):

Drosophila Melanogaster ◽

Natural Populations ◽

Hybrid Dysgenesis ◽

P Element ◽

Strict Sense ◽

Secondary Mutation ◽

Wild Populations ◽

Isofemale Lines ◽

Male Recombination ◽

Element Activity

SummaryMany inbred and isofemale lines derived from wild populations of Drosophila melanogaster were tested for gonadal dysgenic sterility, male recombination and snw secondary mutation. Among them, we have found strains whose dysgenic offspring show negligible sterility, and undetectable male recombination and snw mutation. They can be considered to be neutral strains in the strict sense. Such neutral strains appear to carry only defective P elements in their genomes. Taking the observations of Karess & Rubin (1984) into account, it is suggested that some defective P elements retain the function necessary for P cytotype. Cytotype determination mechanisms are discussed.

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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 element activity and molecular structure in Drosophila melanogaster populations from Firtina Valley, Turkey

Journal of Insect Science ◽

10.1093/jis/14.1.16 ◽

2014 ◽

Vol 14 (1) ◽

Cited By ~ 9

Author(s):

Banu Sebnem Onder ◽

Ozge Erisöz Kasap

Keyword(s):

Molecular Structure ◽

Drosophila Melanogaster ◽

P Element ◽

Element Activity

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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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Tirant stealthily invaded natural Drosophila melanogaster populations during the last century

10.1101/2020.06.10.144378 ◽

2020 ◽

Author(s):

Florian Schwarz ◽

Filip Wierzbicki ◽

Kirsten-André Senti ◽

Robert Kofler

Keyword(s):

Drosophila Melanogaster ◽

Insertion Site ◽

Natural Populations ◽

P Element ◽

Past Century ◽

Time Points ◽

The Past ◽

Living Fossils ◽

Late Discovery ◽

Comprehensive Study

AbstractIt was long thought that solely three different transposable elements - the I-element, the P-element and hobo - invaded natural D. melanogaster populations within the last century. By sequencing the ‘living fossils’ of Drosophila research, i.e. D. melanogaster strains sampled from natural populations at different time points, we show that a fourth TE, Tirant, invaded D. melanogaster populations during the past century. Tirant likely spread in D. melanogaster populations around 1938, followed by the I-element, hobo, and, lastly, the P-element. In addition to the recent insertions of the canonical Tirant, D. melanogaster strains harbour degraded Tirant sequences in the heterochromatin which are likely due to an ancient invasion, possibly predating the split of D. melanogaster and D. simulans. In contrast to the I-element, P-element and hobo, we did not find that Tirant induces any hybrid dysgenesis symptoms. This absence of apparent phenotypic effects may explain the late discovery of the Tirant invasion. Recent Tirant insertions were found in all investigated natural populations. Populations from Tasmania carry distinct Tirant sequences, likely due to a founder effect. By investigating the TE composition of natural populations and strains sampled at different time points, insertion site polymorphisms, piRNAs and phenotypic effects, we provide a comprehensive study of a natural TE invasion.

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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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Localization of P elements, copy number regulation, and cytotype determination in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672300028822 ◽

1990 ◽

Vol 56 (1) ◽

pp. 3-14 ◽

Cited By ~ 35

Author(s):

C. Biémont ◽

S. Ronsseray ◽

D. Anxolabéhère ◽

H. Izaabel ◽

C. Gautier

Keyword(s):

Drosophila Melanogaster ◽

Copy Number ◽

Chromosomal Location ◽

Inbred Lines ◽

P Element ◽

P Elements ◽

Left And Right ◽

Element Activity ◽

Copy Number Regulation

SummarySeventeen highly-inbred lines of Drosophila melanogaster extracted from an M′ strain (in the P/M system of hybrid dysgenesis) were studied for their cytotype and the number and chromosomal location of complete and defective P elements. While most lines were of M cytotype, three presented a P cytotype (the condition that represses P-element activity) and one was intermediate between M and P. All lines were found to possess K.P elements and only eight to bear full-sized P elements. Only the lines with full-sized P elements showed detectable changes in their P-insertion pattern over generations; their rates of gain and of loss of P-element sites were equal to 0·12 and 0·09 per genome, per generation, respectively. There was no correlation between these two rates within lines, suggesting independent transpositions and excisions in the inbred genomes. The results of both Southern blot analysis and in situ hybridization of probes made from left and right sides of the P element strongly suggested the presence of a putative complete P element in region 1A of the X chromosome in the three lines with a P cytotype; the absence of P copy in this 1A region in lines with an M cytotype, favours the hypothesis that the P element inserted in 1A could play a major role in the P-cytotype determination. Insertion of a defective 2 kb P element was also observed in region 93F in 9 of the 13 M lines. The regulation of the P-element copy number in our lines appeared not to be associated with the ratio of full-length and defective P elements.

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