Positive correlation between the occurrence of chromosome breakage and the induction of point mutations associated with male recombination 31.1 MRF system of hybrid dysgenesis in Drosophila melanogaster

Until now, with regard to the hobo system of hybrid dysgenesis, natural populations of Drosophila melanogaster have been investigated using only two criteria: at the molecular level, the presence or absence of XhoI fragments 2·6 kb long or smaller; and/or at the genetic level, the ability to induce gonadal dysgenesis sterility in crosses A (females of an E reference strain crossed with males under test) and A* (females under test crossed with males of an H reference strain). Recently, analyses of laboratory strains using these criteria as well as the mobilization of two reporter genes, the male recombination and the number of ‘TPE’ repeats in the S region, revealed a lack of correlation between the different dysgenic parameters themselves, and also between these parameters and the molecular characteristics of the strains. Thirteen current strains derived from world populations were therefore investigated with regard to all these dysgenic traits, to determine discriminating criteria providing a robust method of classifying natural populations and deducing the dynamics of hobo elements in these populations. We show, as in laboratory strains, a lack of correlation between the parameters studied. Therefore, the significance of each of them as well as the nature of hobo hybrid dysgenesis are discussed, to propose an analysis method of the hobo system applicable to natural populations. According to the geographical distribution of hobo activities in world populations and to the variable polymorphism of the number of ‘TPE’ repeats, we propose a new scenario for the invasion of D. melanogaster by hobo elements.

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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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Germ line aberrations associated with a case of hybrid dysgenesis in Drosophila melanogaster males

Genetics Research ◽

10.1017/s0016672300018267 ◽

1979 ◽

Vol 33 (2) ◽

pp. 137-146 ◽

Cited By ~ 22

Author(s):

William R. Engels

Keyword(s):

Drosophila Melanogaster ◽

Sex Ratio ◽

Germ Line ◽

Hybrid Dysgenesis ◽

Transmission Ratio Distortion ◽

Female Sterility ◽

Male Recombination ◽

Ratio Distortion ◽

Temperature Optima ◽

Sex Ratio Distortion

SUMMARYMale sterility, male recombination, and transmission ratio distortion – all examples of a syndrome known as hybrid dysgenesis in Drosophila melanogaster – were found to involve chromosome–cytoplasm interactions. The latter two have temperature optima near 25° and involve pre-meiotic events. In addition, sex ratio distortion, and induction of certain translocations of the X and Y chromosomes (but not the autosomes) were found to be part of hybrid dysgenesis. Both are caused by chromosome–cytoplasm interactions with pre-meiotic events playing a crucial role. The results agree with previous data on female sterility in hybrid dysgenesis, which also has cytoplasmic components and premeiotic origins.

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Hybrid dysgenesis in drosophila melanogaster: The frequency and distribution of male recombination events

Heredity ◽

10.1038/hdy.1984.21 ◽

1984 ◽

Vol 52 (2) ◽

pp. 189-202 ◽

Cited By ~ 2

Author(s):

Paul Eggleston

Keyword(s):

Drosophila Melanogaster ◽

Hybrid Dysgenesis ◽

Male Recombination

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Male Recombination in Dysgenic Hybrids of Drosophila Melanogaster: Chromosome Breakage or Mitotic Crossing-Over?

Australian Journal of Biological Sciences ◽

10.1071/bi9780303 ◽

1978 ◽

Vol 31 (3) ◽

pp. 303 ◽

Cited By ~ 6

Author(s):

JA Sved

Keyword(s):

Drosophila Melanogaster ◽

Chromosome Breakage ◽

Mitotic Recombination ◽

Large Series ◽

Crossing Over ◽

Equal Frequency ◽

Male Recombination ◽

Recombination Model ◽

Series Of Experiments ◽

Balancer Chromosome

Recombinant second chromosomes from dysgenic male hybrids of D. melanogaster have been made homozygous using a Curly balancer chromosome technique. Most of the chromosome homozygotes produced have apparently normal viability. The incidence of newly produced lethals, while as high as 5-10%, is not significantly higher than in non-recombinant chromosomes. Thus male recombination and mutation appear to occur independently of each other, rather than in the same gametes as would be expected if both were simultaneously produced by chromosome breakage and reunion. Furthermore, a summary of recombination clusters over a large series of experiments suggests that reciprocal and non-reciprocal clusters occur with approximately equal frequency. This is in agreement with predictions from a four-strand mitotic recombination model.

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Structure, frequency and distribution of P elements in relation to P—M hybrid dysgenic male recombination in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672300028123 ◽

1989 ◽

Vol 53 (3) ◽

pp. 163-171 ◽

Cited By ~ 1

Author(s):

K. A. Exley ◽

P. Eggleston

Keyword(s):

Drosophila Melanogaster ◽

Egg Production ◽

Polytene Chromosomes ◽

Element Distribution ◽

Hybrid Dysgenesis ◽

P Element ◽

Male Recombination ◽

P Elements ◽

Egg Hatchability ◽

The Third

SummaryThe frequency and distribution of P elements were investigated in the third chromosomes of two wild-type strains of Drosophila melanogaster using in situ hybridization of biotinylated probes to the polytene chromosomes. The relationship between these data and the extent of hybrid dysgenesis was determined through assays of egg production, egg hatchability (F2 embryo lethality), snw destabilization and male recombination along the third chromosome. The results suggest that P-element distribution, frequency and structure are all contributory factors in the regulation of hybrid dysgenesis. Texas 6 was shown consistently to be a stronger P strain than Texas 1, eliciting greater reductions in fertility, more extensive snw destabilization and higher frequencies of male recombination. Clustering of male recombination events, arising from pre-meiotic crossing over, was evident among the dysgenic progeny of each strain. Male recombination and snw destabilization were independently distributed among the dysgenic males studied, suggesting that these traits represent separate P-mediated functions. The third chromosome male recombination maps produced by the two strains differed significantly from each other and from the published female meiotic and polytene chromosome maps. Male recombination breakpoints were associated with the original distribution of P sequences in the two strains and the results suggest that this relationship may be closer for potentially complete P factors than for P sequences in general. An analysis of sub-lines derived from individual recombinant males revealed that chromosomal breakpoints could also be associated with novel insertions following P-element transposition.

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Chromosomal Contamination for Male Recombination in Drosophila melanogaster

Australian Journal of Biological Sciences ◽

10.1071/bi9820645 ◽

1982 ◽

Vol 35 (6) ◽

pp. 645

Author(s):

JA Sved ◽

DJ Colgan

Keyword(s):

Drosophila Melanogaster ◽

Homologous Chromosome ◽

Hybrid Dysgenesis ◽

Male Recombination ◽

System A ◽

Two Systems

It has previously been shown that the ability to induce male recombination may be passed from one chromosome to another, not necessarily homologous, chromosome. This phenomenon is investigated, using strains known to interact in the P-M system of hybrid dysgenesis, and is shown to be analogous to the phenomenon of 'chromosomal contamination' in the I-R system of hybrid dysgenesis, in that the passage of properties from one chromosome to another is correlated with other manifestations of dysgenesis. Unlike the I-R system, contamination can occur in males as well as in females in the P-M system, a result which is consistent with other differences between the two systems. The contaminated chromosome acquires only a portion of the dysgenic properties of the original chromosome, and the inheritance is unstable over more than a few generations.

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Studies on male recombination in a Southern Greek Drosophila melanogaster population

Genetics Research ◽

10.1017/s0016672300017948 ◽

1978 ◽

Vol 31 (2) ◽

pp. 187-196 ◽

Cited By ~ 25

Author(s):

George Yannopoulos

Keyword(s):

Drosophila Melanogaster ◽

Elevated Temperatures ◽

Chromosomal Abnormalities ◽

Chromosome Abnormality ◽

Chromosome Breakage ◽

Cross Effect ◽

Cytoplasmic Factor ◽

Male Recombination ◽

Anaphase Bridges ◽

Southern Greece

SUMMARYA combined cytological and genetic analysis has been carried out to determine whether the spontaneous male recombination associated with a line of Drosophila melanogaster derived from Southern Greece (31.1 MRF) involves chromosome breakage and random reunion. In all crosses showing male recombination, extensive abnormalities involving anaphase bridges and fragments were found at first and second meiotic divisions. This confirms that the low level of recombination associated with male recombination lines is not produced by normal, controlled crossing-over of the type found in females, but by chance reunions, following more erratic breakage events at first and second anaphase. In addition the occurrence of some limited premeiotic recombination cannot be excluded. The 31.1 MRF system shows higher recombination levels at elevated temperatures (29 °C) and chromosome abnormality frequency is also greatly increased. The 31.1 MRF induces both male recombination and chromosomal abnormalities at meiosis when it is inherited from females deriving their cytoplasm from stock other than CyL4/Pm. It is concluded that this factor acts independently of sex and that the reciprocal cross effect is caused by a cytoplasmic factor which the 31.1/CyL4 strain inherited from the CyL4/Pm stock.

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Hybrid dysgenesis in Drosophila melanogaster: rules of inheritance of female sterility

Genetics Research ◽

10.1017/s001667230001836x ◽

1979 ◽

Vol 33 (3) ◽

pp. 219-236 ◽

Cited By ~ 122

Author(s):

William R. Engels

Keyword(s):

Drosophila Melanogaster ◽

Hybrid Dysgenesis ◽

Female Sterility ◽

Independent Action ◽

Male Recombination ◽

Reciprocal Crosses ◽

Mendelian Factor ◽

Entire Cell ◽

Series Of Experiments ◽

Mode Of Inheritance

SUMMARYHybrid dysgenesis has been described as a syndrome of aberrant traits including sterility, male recombination, and mutation, which occurs in some inter-strain hybrids of Drosophila, but only from one of the two reciprocal crosses. In a series of experiments in which hybrids of various pedigrees were tested for sterility, it was found that a case of hybrid dysgenesis could be most easily interpreted as the interaction of two components. One component was found to be a polygenic Mendelian factor linked to each of the major chromosomes of π2, the paternally contributing strain (‘P strain’). These chromosomes were capable of causing sterility when inherited from either parent, provided the appropriate maternal component was also inherited. The ability to transmit this maternal component was designated ‘cytotype’ to indicate that it is a property of the entire cell. It was possible to classify nearly all hybrid females as either P or M cytotype on the basis of their ability to produce sterile daughters. All daughters of the M-cytotype mothers were susceptible to the sterilizing effects of the π2 chromosome, whereas all, or nearly all daughters of P-cytotype mothers were immune. When more than one of the π2 chromosomes were received by daughters of M-cytotype females, chromosomal interactions could be detected statistically, but the model of independent action remained a useful approximation. Cytotype was shown to be determined by chromosomal factors, but with limited cytoplasmic transmission. This unusual mode of inheritance can be compared with other cases of hybrid dysgenesis where the behaviour resembles that of self-replicating cytoplasmic particles which are dependent on certain chromosomes. The lack of sterility from intra-strain crosses can be explained by the fact that chromosomes capable of causing sterility also induce the P cytotype, and thus prevent sterility in the next generation.

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SPONTANEOUS CHROMOSOME BREAKAGE AT MALE MEIOSIS ASSOCIATED WITH MALE RECOMBINATION IN DROSOPHILA MELANOGASTER

Genetics ◽

10.1093/genetics/88.1.93 ◽

1978 ◽

Vol 88 (1) ◽

pp. 93-107

Author(s):

S A Henderson ◽

R C Woodruff ◽

J N Thompson

Keyword(s):

Drosophila Melanogaster ◽

Marker Gene ◽

Low Frequency ◽

Chromosome Breakage ◽

Male Meiosis ◽

Male Recombination ◽

Anaphase Bridges ◽

Inversion Heterozygote ◽

Single Fragment ◽

Perfectly Normal

ABSTRACT An inbred line (OKI) of Drosophila melanogaster, recently derived from a natural population in Oklahoma, has been found by WOODRUFF and THOMPSON to exhibit a low frequency of spontaneous male recombination when outcrossed to marker stocks. There is also a reciprocal-cross effect, such that recombination is found only if OK1 males are used in the initial cross. When OK1 females are used, however, male recombinatioii is again found if their male progeny are used for a subsequent cross,-In the present cytological analysis, chromosome behavior at male meiosis was studied in reciprocal crosses between the OK1 line and both a marker gene stock and an inversion stock. If the recombination events were "conventional" and premeiotic (gonial) in origin, no chromosome aberrations would be expected during meiosis. If they were "conventional" and meiotic, some dicentric bridges with free fragments would be expected in the inversion heterozygote, but none should be present in the marker gene cross.—The results demonstrated that the occurrence of recombination in males is most likely a meiotic event, though the occurrence of some limited premeiotic recombination can not be disproven. Meiosis was found to be perfectly normal in all crosses lacking male recombination. In all of the inversion stock and noninversion marker stock crosses that showed male recombination, however, anaphase bridges were found at both first and second meiotic divisions. These were often accompanied by more than the single fragment expected from a conventional inversion bridge and fragment situation. In extreme cases, almost complete pulverization of one or more autosomes was found.—All metaphase I stages were perfectly normal, suggesting that no comparable breakage occurs in premeiotic gonial mitoses. The form of chromosome damage is similar in many ways to that produced by some DNA synthesis inhibitors, or by some viral or mycoplasma infections. This possibility is discussed, and some of the evolutionary implications of the system are briefly considered.

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