Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| the y chromosomes of drosophila simulans are highly polymorphic for their ability to suppress sex-ratio drive. | the sex-ratio trait, known in several species of drosophila including d. simulans, results from meiotic drive of the x chromosome against the y. males that carry a sex-ratio x chromosome produce strongly female-biased progeny. in d. simulans, drive suppressors have evolved on the y chromosome and on the autosomes. both the frequency of sex-ratio x and the strength of the total drive suppression (y-linked and autosomal) vary widely among geographic populations of this worldwide species. we have i ... | 2001 | 11392391 |
| two novel pao-like retrotransposons (kamikaze and yamato) from the silkworm species bombyx mori and b. mandarina: common structural features of pao-like elements. | to characterize the structural features common to pao-like retrotransposons, we analyzed two lambda phage clones which contain the pao-like elements from the silkworm species bombyx mori and b. mandarinia, and copies of pao itself and ninja of drosophila simulans, amplified by pcr. we previously identified two randomly amplified polymorphic dnas (rapds), w-kamikaze and w-yamato, from b. mori and b. mandarina, which are part of two novel pao-like retrotransposons, kamikaze and yamato, respectivel ... | 2001 | 11361350 |
| cryptic reproductive isolation in the drosophila simulans species complex. | forms of reproductive isolation that act after copulation but before fertilization are potentially important components of speciation, but are studied only infrequently. we examined postmating, prezygotic reproductive isolation in three hybridizations within the drosophila simulans species complex. we allowed females to mate only once, observed and timed all copulations, dissected a subset of the females to track the storage and retention of sperm, examined the number and hatchability of eggs la ... | 2001 | 11263748 |
| recombination and the frequency spectrum in drosophila melanogaster and drosophila simulans. | most "tests of neutrality" assess whether particular data sets depart from the predictions of a standard neutral model with no recombination. for drosophila, where nuclear polymorphism data routinely show evidence of genetic exchange, the assumption of no recombination is often unrealistic. in addition, while conservative, this assumption is made at the cost of a great loss in power. perhaps as a result, tests of the frequency spectrum based on zero recombination suggest an adequate fit of droso ... | 2001 | 11230530 |
| contrasting patterns of x-linked and autosomal nucleotide variation in drosophila melanogaster and drosophila simulans. | surveys of molecular variation in drosophila melanogaster and drosophila simulans have suggested that diversity outside of africa is a subset of that within africa. it has been argued that reduced levels of diversity in non-african populations reflect a population bottleneck, adaptation to temperate climates, or both. here, i summarize the available single-nucleotide polymorphism data for both species. a simple "out of africa" bottleneck scenario is consistent with geographic patterns for loci o ... | 2001 | 11230529 |
| mechanisms of conspecific sperm precedence in drosophila. | the postmating, prezygotic isolating mechanism known as conspecific sperm precedence (csp) may play an important role in speciation, and understanding the mechanism of csp is important in reconstructing its evolution. when a drosophila simulans female mates with both a d. simulans male and a d. mauritiana male, the vast majority of her progeny are fathered by d. simulans, regardless of the order of mating. the dearth of hybrid progeny does not result from inviability of eggs fertilized by hetero ... | 2000 | 11209779 |
| developmental expression of the 412 retrotransposon in natural populations of d. melanogaster and d. simulans. | we analysed the pattern of expression of retrotransposon 412 through developmental stages in various populations of drosophila simulans and d. melanogaster differing in 412 copy number. we found that the 412 expression pattern varied greatly between populations of both species, indicating that such patterns were not entirely species-specific. in d. simulans, total transcripts increased with number of 412 copies in the chromosomes when this number was low, and then decreased for high copy numbers ... | 2000 | 11204969 |
| wolbachia neither induces nor suppresses transcripts encoding antimicrobial peptides. | wolbachia are intracellular maternally inherited microorganisms that are associated with reproductive abnormalities such as cytoplasmic incompatibility (ci), feminization and parthenogenesis in the various arthropod species they infect. surveys indicate that these bacteria infect more than 16% of all insect species as well as isopods, mites and nematodes, making wolbachia one of the most ubiquitous parasites yet described. however, nothing is known about the interactions of this bacterium with t ... | 2000 | 11122472 |
| nucleotide variation at the yellow gene region is not reduced in drosophila subobscura: a study in relation to chromosomal polymorphism. | in contrast to drosophila melanogaster and drosophila simulans, the yellow (y) gene region of drosophila subobscura is not located in a region with a strong reduction in recombination. in addition, this gene maps very close to the breakpoints of different inversions that segregate as polymorphic in natural populations of d. subobscura. therefore, levels of variation at the y gene region in this species relative to those found in d. melanogaster and d. simulans may be affected not only by the cha ... | 2000 | 11110911 |
| expression of cytoplasmic incompatibility in drosophila simulans and its impact on infection frequencies and distribution of wolbachia pipientis. | the aim of this study is to examine the expression of cytoplasmic incompatibility and investigate the distribution and population frequencies of wolbachia pipientis strains in drosophila simulans. nucleotide sequence data from 16s rdna and a wolbachia surface protein coding sequence and cytoplasmic incompatibility assays identify four distinct wolbachia strains: wha, wri, wma, and wau. the levels of cytoplasmic incompatibility between six lines carrying these strains of bacteria and three contro ... | 2000 | 11108593 |
| the population genetics of the origin and divergence of the drosophila simulans complex species. | the origins and divergence of drosophila simulans and close relatives d. mauritiana and d. sechellia were examined using the patterns of dna sequence variation found within and between species at 14 different genes. d. sechellia consistently revealed low levels of polymorphism, and genes from d. sechellia have accumulated mutations at a rate that is approximately 50% higher than the same genes from d. simulans. at synonymous sites, d. sechellia has experienced a significant excess of unpreferred ... | 2000 | 11102384 |
| characterization of defects in adult germline development and oogenesis of sterile and rescued female hybrids in crosses between drosophila simulans and drosophila melanogaster. | crosses between drosophila melanogaster and d. simulans normally result in progeny that are either inviable or sterile. recent discovery of strains that rescue these inviability and sterility phenotypes has made it possible to study the developmental basis of reproductive isolation between these two species in greater detail. by producing both rescued and unrescued hybrids and examining the protein product staining patterns of genes known to be involved in early germline development and gametoge ... | 2000 | 11069139 |
| nonrandom mating in drosophila melanogaster laboratory populations derived from closely adjacent ecologically contrasting slopes at "evolution canyon". | ecological differentiation of natural populations of drosophila melanogaster, drosophila simulans, and another drosophilid, zaprionus tuberculatus, in "evolution canyon," mount carmel, israel, is well established. the fitness complex of d. melanogaster includes oviposition temperature preferences, tolerance to high temperature, drought stress and starvation, and different longevity patterns. this remarkable differentiation has evolved despite small interslope distances (only 100-400 m), within e ... | 2000 | 11050149 |
| wolbachia segregation rate in drosophila simulans naturally bi-infected cytoplasmic lineages. | wolbachia are maternally transmitted endocellular bacteria infecting several arthropod species. in order to study wolbachia segregation rate, drosophila simulans females from an indo-pacific population (seychelles) bi-infected by the two wolbachia variants wha and wno were backcrossed to uninfected males in two conditions. in the first case, seychelles males from a stock cured from its wolbachia by tetracycline treatment were used. in the second case, the males came from a naturally uninfected t ... | 2000 | 11012722 |
| high copy numbers of multiple transposable element families in an australian population of drosophila simulans. | sudden mobilization of transposable elements in drosophila is a well-reported phenomenon but one that usually affects no more than a few elements (one to four). we report here the existence of a d. simulans natural population (canberra) from australia, which had high copy numbers for various transposable elements (transposons, ltr retrotransposons and non-ltr retrotransposons). the impact of transposable elements on the host genome and populations is discussed. | 2000 | 11006639 |
| transposable elements and genome evolution: the case of drosophila simulans. | drosophila simulans presents a large variation in copy number among various transposable elements (tes) and among natural populations for a given element. some elements such as hms beagle, blood, flea, tirant, coral, prygun, jockey, f, nomade and mariner are absent in most populations, except in one or two which have copies on their chromosome arms. this suggests that some tes are being awakened in d. simulans and are in the process of invading the species while it is colonizing the world. the e ... | 1999 | 10952204 |
| high density of long dinucleotide microsatellites in drosophila subobscura. | we isolated 96 dinucleotide repeats with five or more tandemly repeated units from a subgenomic drosophila subobscura library. the mean repeat unit length of microsatellite clones in d. subobscura is 15, higher than that observed in other drosophila species. population variation was assayed in 32-40 chromosomes from barcelona, spain, using 18 randomly chosen microsatellite loci. positive correlation between measures of variation and perfect repeat length measures (mean size, most common, and lon ... | 2000 | 10908646 |
| comparative genomics of mitochondrial dna in drosophila simulans. | the current study compares the nucleotide variation among 22 complete mitochondrial genomes of the three distinct drosophila simulans haplotypes with intron 1 of the alcohol dehydrogenase-related locus. this is the first study to investigate the sequence variation of multiple complete mitochondrial genomes within distinct mitochondrial haplotypes of a single species. patterns of variation suggest distinct forces are influencing the evolution of mitochondrial dna (mtdna) and autosomal dna in d. s ... | 2000 | 10903373 |
| structural and genetic studies of the proliferation disrupter genes of drosophila simulans and d. melanogaster. | to examine whether structural and functional differences exist in the proliferation disrupter (prod) genes between drosophila simulans and d. melanogaster, we analyzed and compared both genes. the exon-intron structure of the prod genes was found to be the same--three exons were interrupted by two introns, although a previous report suggested that only one intron existed in d. melanogaster. the prod genes of d. simulans and d. melanogaster both turn out to encode 346 amino acids, not 301 as prev ... | 1999 | 10897796 |
| location of shfr, a new gene that rescues hybrid female viability in crosses between drosophila simulans females and d. melanogaster males. | as a rule, progeny of crosses between drosophila simulans females and d. melanogaster males are formed by sterile males, because females die as embryos. however, populations of these species have been found that produce a certain frequency of viable hybrid females. we have found that 94% of the females of a d. simulans population from tel aviv gave hybrid progenies with both sexes. the segregation of phenotypes with different rescue success adjusts to the action of a single, dominant, zygotic-ac ... | 2000 | 10886378 |
| reduced x-linked nucleotide polymorphism in drosophila simulans. | population genetic theory predicts that selectively driven changes of allele frequency for both beneficial and deleterious mutants reduce polymorphism at tightly linked sites. all else being equal, these reductions in polymorphism are expected to be greater when recombination rates are lower. therefore, the empirical observation of a positive correlation between recombination rates and amounts of dna polymorphism across the drosophila melanogaster genome can be explained by two very different ty ... | 2000 | 10823947 |
| offsetting effects of wolbachia infection and heat shock on sperm production in drosophila simulans: analyses of fecundity, fertility and accessory gland proteins. | infection in drosophila simulans with the endocellular symbiont wolbachia pipientis results in egg lethality caused by failure to properly initiate diploid development (cytoplasmic incompatibility, ci). the relationship between wolbachia infection and reproductive factors influencing male fitness has not been well examined. here we compare infected and uninfected strains of d. simulans for (1) sperm production, (2) male fertility, and (3) the transfer and processing of two accessory gland protei ... | 2000 | 10790392 |
| the phylogeny of closely related species as revealed by the genealogy of a speciation gene, odysseus. | molecular differentiation between races or closely related species is often incongruent with the reproductive divergence of the taxa of interest. shared ancient polymorphism and/or introgression during secondary contact may be responsible for the incongruence. at loci contributing to speciation, these two complications should be minimized (1, 2); hence, their variation may more faithfully reflect the history of the species' reproductive differentiation. in this study, we analyzed dna polymorphis ... | 2000 | 10779562 |
| adaptive evolution of relish, a drosophila nf-kappab/ikappab protein. | nf-kappab and ikappab proteins have central roles in regulation of inflammation and innate immunity in mammals. homologues of these proteins also play an important role in regulation of the drosophila immune response. here we present a molecular population genetic analysis of relish, a drosophila nf-kappab/ikappab protein, in drosophila simulans and d. melanogaster. we find strong evidence for adaptive protein evolution in d. simulans, but not in d. melanogaster. the adaptive evolution appears t ... | 2000 | 10757765 |
| the evolution of an alpha-esterase pseudogene inactivated in the drosophila melanogaster lineage. | previous analyses of the alpha-esterase cluster of drosophila melanogaster revealed 10 active genes and the dmalphae4a-psi pseudogene. here, we reconstruct the evolution of the pseudogene from the sequences of 12 alleles from widely scattered d. melanogaster populations and single alleles from drosophila simulans and drosophila yakuba. all of the dmalphae4a-psi alleles contain numerous inactivating mutations, suggesting that pseudogene alleles are fixed in natural populations. several lines of e ... | 2000 | 10742048 |
| genetic analysis of speciation by means of introgression into drosophila melanogaster. | in the last decade, the genetic basis of reproductive isolation has been shown to be surprisingly polygenic, and yet even the most efficient system currently in use could lend itself to molecular analysis only in highly selected cases. by extending the recent discovery of fertility rescue between drosophila melanogaster and drosophila simulans, we show that this hybridization can permit systematic and precise delineation of the genetic and molecular basis of speciation. in a region of 5% of the ... | 2000 | 10706624 |
| [analysis of differences in the structure of ribosomal dna from two sibling species: drosophila melanogaster and drosophila simulans]. | southern-blot hybridization studies have revealed structural differences within the ribosomal dna clusters of two sibling species, drosophila melanogaster and drosophila simulans. the approach used was shown to be suitable for taxonomic identification of the species examined. | 1999 | 10687091 |
| genetic architecture of a morphological shape difference between two drosophila species. | the size and shape of the posterior lobe of the male genital arch differs dramatically between drosophila simulans and d. mauritiana. this difference can be quantified with a morphometric descriptor (pc1) based on elliptical fourier and principal components analyses. the genetic basis of the interspecific difference in pc1 was investigated by the application of quantitative trait locus (qtl) mapping procedures to segregating backcross populations. the parental difference (35 environmental standa ... | 2000 | 10628989 |
| sex-ratio meiotic drive in drosophila simulans is related to equational nondisjunction of the y chromosome. | the sex-ratio trait, an example of naturally occurring x-linked meiotic drive, has been reported in a dozen drosophila species. males carrying a sex-ratio x chromosome produce an excess of female offspring caused by a deficiency of y-bearing sperm. in drosophila simulans, such males produce approximately 70-90% female offspring, and 15-30% of the male offspring are sterile. here, we investigate the cytological basis of the drive in this species. we show that the sex-ratio trait is associated wit ... | 2000 | 10628983 |
| microsatellite markers for interspecific mapping of drosophila simulans and d. sechellia. | 1999 | 10620238 | |
| a quantitative genetic analysis of male sexual traits distinguishing the sibling species drosophila simulans and d. sechellia. | a quantitative trait locus (qtl) genetic analysis of morphological and reproductive traits distinguishing the sibling species drosophila simulans and d. sechellia was carried out in a backcross design, using 38 markers with an average spacing of 8.4 cm. the direction of qtl effects for the size of the posterior lobe was consistent across the identified qtl, indicating directional selection for this trait. directional selection also appears to have acted on testis length, indicating that sexual s ... | 1999 | 10581276 |
| the genetics and evolution of the mariner transposable element in drosophila simulans: worldwide distribution and experimental population dynamics. | we have studied both the frequency and biogeographical distribution of the transposable dna element mariner in natural populations of drosophila simulans and the short-term evolutionary characteristics of mariner in experimental populations. the mariner element has been identified in natural populations of d. simulans from africa, europe, the middle east, japan, australia, several pacific islands, north america, and south america. only four lines out of 296 were devoid of active mariner elements ... | 1999 | 10568259 |
| wake up of transposable elements following drosophila simulans worldwide colonization. | transposable elements (tes) make up around 10%-15% of the drosophila melanogaster genome, but its sibling species drosophila simulans carries only one third as many such repeat sequences. we do not, however, have an overall view of copy numbers of the various classes of tes (long terminal repeat [ltr] retrotransposons, non-ltr retrotransposons, and transposons) in genomes of natural populations of both species. we analyzed 34 elements in individuals from various natural populations of these spec ... | 1999 | 10486980 |
| population structure among african and derived populations of drosophila simulans: evidence for ancient subdivision and recent admixture. | previous studies based on allozyme variation have found little evidence for genetic differentiation in drosophila simulans. on the basis of dna sequence variation at two nuclear loci in four african populations of d. simulans, we show that there is significant structure to d. simulans populations within africa. variation at one of the loci, vermilion, appears to be neutral and supports an eastern african origin for european and american populations. samples from the west indies, europe, and nort ... | 1999 | 10471714 |
| centromeres from telomeres? the centromeric region of the y chromosome of drosophila melanogaster contains a tandem array of telomeric het-a- and tart-related sequences. | cytological and cytogenetic studies have previously defined the region needed for centromeric function in the y chromosome of drosophila melanogaster. we have identified a yac clone that originated from this region. molecular analysis of the yac and genomic dnas has allowed the description of a satellite dna made of telomeric het-a- and tart-derived sequences and the construction of a long-range physical map of the heterochromatic region h18. sequences within the yac clone are conserved in the c ... | 1999 | 10454639 |
| a stable triple wolbachia infection in drosophila with nearly additive incompatibility effects. | drosophila simulans strains infected with three different wolbachia strains were generated by experimental injection of a third symbiont into a naturally double-infected strain. this transfer led to a substantial increase in total wolbachia density in the host strain. each of the three symbionts was stably transmitted in the presence of the other two. triple-infected males were incompatible with double-infected females. no evidence was obtained for interference between modification effects of th ... | 1999 | 10383683 |
| nucleotide variation at the runt locus in drosophila melanogaster and drosophila simulans. | intra- and interspecific nucleotide variation for the major developmental gene runt in drosophila was studied in d. melanogaster and d. simulans. the 1.5-kb protein-coding region and the 0.4-kb intron of the runt gene were sequenced for 11 alleles in each species. the d. melanogaster alleles originated from east africa. estimated parameters of intraspecific variation in d. melanogaster (exons: theta = 0.018, pi = 0.018; intron: theta = 0.014, pi = 0.014) and d. simulans (exons: theta = 0.007, pi ... | 1999 | 10368951 |
| polymorphism in structure of the retrotransposable element 412 in drosophila simulans and d. melanogaster populations. | the structure of the 412 retrotransposable element was investigated in various natural populations of d. melanogaster and d. simulans by a restriction enzyme analysis. we show that although the canonical structure of the 412 element was the same in both species, a high structural polymorphism existed with various rearranged elements. a 412 family was thus composed of heterogeneous copies of different sizes, with a large proportion of full-size copies. d. simulans had more rearranged copies than ... | 1999 | 10352229 |
| molecular identification of the active ninja retrotransposon and the inactive aurora element in drosophila simulans and d. melanogaster. | how transposable elements evolve is a key facet in understanding of spontaneous mutation and genomic rearrangements in various organisms. one of the best ways to approach this question is to study a newly evolved transposable element whose presence is restricted to a specific population or strain. the retrotransposons ninja and aurora may provide insights into the process of their evolution, because of their contrasting characteristics, even though they show high sequence identity. the ninja ret ... | 1998 | 10333568 |
| horizontal transfer of wolbachia between phylogenetically distant insect species by a naturally occurring mechanism. | wolbachia is a genus of alpha-proteobacteria found in obligate intracellular association with a wide variety of arthropods, including an estimated 10-20% of all insect species [1]. wolbachia represents one of a number of recently identified 'reproductive parasites' [2] which manipulate the reproduction of their hosts in ways that enhance their own transmission [3] [4] [5] [6] [7] [8] [9]. the influence of wolbachia infection on the dynamics of host populations has focused considerable interest o ... | 1999 | 10209097 |
| cross-order transfer of wolbachia from muscidifurax uniraptor (hymenoptera: pteromalidae) to drosophila simulans (diptera: drosophilidae). | bacteria of the genus wolbachia are widespread in arthropods and can induce different effects on the host such as cytoplasmic incompatibility (ci), thelytoky (t) or feminization (f). in some wolbachia-infected hosts, no effect (n) has been found. successful transfer of wolbachia by microinjection from one host to an uninfected one has been established with ci, f, n-wolbachia but not with t-wolbachia. in this paper a transfer experiment of t-wolbachia from the parasitoid muscidifurax uniraptor to ... | 1999 | 10098265 |
| survey of malathion resistance and avermectin susceptibility in field populations of drosophila melanogaster (diptera: drosophilidae) and d. simulans. | populations of drosophila melanogaster (meigen) and drosophila simulans (sturtevant) from various geographic locations in north america and elsewhere were sampled to assess the distribution of malathion resistance and avermectin tolerance. comparisons are made to previous reports of a differential response to malathion selection in these species. results indicate that for malathion, resistance is widespread in d. simulans but varies considerably in d. melanogaster. for avermectins, although the ... | 1998 | 9887681 |
| inferring the fitness effects of dna mutations from polymorphism and divergence data: statistical power to detect directional selection under stationarity and free recombination. | the fitness effects of classes of dna mutations can be inferred from patterns of nucleotide variation. a number of studies have attributed differences in levels of polymorphism and divergence between silent and replacement mutations to the action of natural selection. here, i investigate the statistical power to detect directional selection through contrasts of dna variation among functional categories of mutations. a variety of statistical approaches are applied to dna data simulated under sawy ... | 1999 | 9872962 |
| microsatellite variation in drosophila melanogaster and drosophila simulans: a reciprocal test of the ascertainment bias hypothesis. | interspecific comparisons of microsatellite loci have repeatedly shown that the loci are longer and more variable in the species from which they are derived (the focal species) than are homologous loci in other (nonfocal) species. there is debate as to whether this is due to directional evolution or to an ascertainment bias during the cloning and locus selection processes. this study tests these hypotheses by performing a reciprocal study. eighteen perfect dinucleotide microsatellite loci identi ... | 1998 | 9866198 |
| distribution of the retrotransposable element 412 in drosophila species. | copy numbers of sequences homologous to the drosophila melanogaster retrotransposable element 412, their distribution between the chromosome arms and the chromocenter, and whether they contain full-size copies were analyzed for 55 species of the drosophila genus. element 412 insertion sites were detected on the chromosome arms of d. melanogaster, drosophila simulans, and a few species of the obscura group, but the chromocenter was labeled in almost all species. the presence of element 412 sequen ... | 1998 | 9866195 |
| duplication of the rdl gaba receptor subunit gene in an insecticide-resistant aphid, myzus persicae. | resistance to cyclodiene insecticides is associated with replacements of a single amino acid (alanine 302) in a gamma-aminobutyric acid (gaba) receptor subunit encoded by the single-copy gene resistance to dieldrin (rdl). alanine 302 is predicted to reside within the second membrane-spanning region of the rdl receptor, a region that is thought to line the integral chloride ion channel pore. in all cyclodiene-resistant insects studied to date, this same alanine residue is replaced either by a ser ... | 1998 | 9862468 |
| characterization of a hypermutable strain of drosophila simulans. | a hypermutable strain of drosophila simulans that originated from a single spontaneous mutant male was characterized. seven different mutations were isolated from roughly 100 generations of offspring. the genetic analysis of the viable mutants showed two mutations on the x chromosome, one in the lozenge locus and the other in the ruby gene. the autosomic mutations characterized were a dpp-heldout-like, a blistered-like and a homoeotic dominant mutant with an antenna-to-leg transformation and ect ... | 1998 | 9849620 |
| genetic variation and differentiation at microsatellite loci in drosophila simulans. evidence for founder effects in new world populations. | drosophila simulans isofemale lines from africa, south america, and two locations in north america were surveyed for variation at 16 microsatellite loci on the x, second, and third chromosomes, and 18 microsatellites, which are unmapped. d. simulans is thought to have colonized new world habitats only relatively recently (within the last few hundred years). consistent with a founder effect occurring as colonizers moved into these new world habitats, we find less microsatellite variability in nor ... | 1998 | 9755208 |
| hidden effects of x chromosome introgressions on spermatogenesis in drosophila simulans x d. mauritiana hybrids unveiled by interactions among minor genetic factors. | one of the most frequent outcomes of interspecific hybridizations in drosophila is hybrid male sterility. genetic dissection of this reproductive barrier has revealed that the number of responsible factors is very high and that these factors are frequently engaged in complex epistatic interactions. traditionally, research strategies have been based on contrasting introgressions of chromosome segments that produce male sterility with those that allow fertility. few studies have investigated the p ... | 1998 | 9755205 |
| a temperature cline in copy number for 412 but not roo/b104 retrotransposons in populations of drosophila simulans. | the copy number of the retrotransposable element 412 of drosophila simulans from populations collected worldwide shows a negative correlation with minimum temperature. no association was detected for the roo/b104 element. the possibility that selective pressures might regulate the 412 copy number in these natural populations is supported by detection of selection against the detrimental effects of 412 insertions (estimated by the proportion of insertions on the x chromosome in comparison with th ... | 1998 | 9699309 |
| sex-related genes, directional sexual selection, and speciation. | reproductive isolation and speciation can result from the establishment of either premating or postmating barriers that restrict gene flow between populations. recent studies of speciation have been dominated by a molecular approach to dissect the genetic basis of hybrid male sterility, a specific form of postmating reproductive isolation. however, relatively little attention has been paid to the evolution of genes involved in premating isolation and genes generally involved in other sex-related ... | 1998 | 9656489 |
| nucleotide variation in the triosephosphate isomerase (tpi) locus of drosophila melanogaster and drosophila simulans. | dna sequence variation in a 1.1-kb region including the coding portion of the tpi locus was examined in 25 homozygous third-chromosome lines of drosophila melanogaster, nine lines of drosophila simulans, and one line of drosophila yakuba. our data show that the widespread allozyme polymorphism observed in cosmopolitan d. melanogaster is due to a glutamic acid substitution occurring in a phylogenetically conserved lysine that has been identified as part of the "hinged-lid" active site of the enzy ... | 1998 | 9615457 |
| rate variation of dna sequence evolution in the drosophila lineages. | rate constancy of dna sequence evolution was examined for three species of drosophila, using two samples: the published sequences of eight genes from regions of the normal recombination rates and new data of the four as-c (ac, sc, l'sc and ase) and ci genes. the as-c and ci genes were chosen because these genes are located in the regions of very reduced recombination in drosophila melanogaster and their locations remain unchanged throughout the entire lineages involved, yielding less effect of a ... | 1998 | 9611206 |
| accumulation of transposable elements in the heterochromatin and on the y chromosome of drosophila simulans and drosophila melanogaster. | the elements of the transposon families g, copia, mdg 1, 412, and gypsy that are located in the heterochromatin and on the y chromosome have been identified by the southern blotting technique in drosophila simulans and d. melanogaster populations. within species, the abundance of such elements differs between transposon families. between species, the abundance in the heterochromatin and on the y chromosome of the elements of the same family can differ greatly suggesting that differences within a ... | 1998 | 9608048 |
| isolation of protease-free alcohol dehydrogenase (adh) from drosophila simulans and several homozygous and heterozygous drosophila melanogaster variants. | the enzyme alcohol dehydrogenase (adh) from several naturally occurring adh variants of drosophila melanogaster and drosophila simulans was isolated. affinity chromatography with the ligand cibacron blue and elution with nad+ showed similar behavior for d. melanogaster adh-ff, adh-71k, and d. simulans adh. introduction of a second cibacron blue affinity chromatography step, with gradient elution with nad+, resulted in pure and stable enzymes. d. melanogaster adh-ss cannot be eluted from the affi ... | 1998 | 9562904 |
| overcoming cytoplasmic incompatibility in drosophila. | the endocellular microbe wolbachia pipientis infects a wide variety of invertebrate species, in which its presence is closely linked to a form of reproductive failure termed cytoplasmic incompatibility (ci). ci renders infected males unable to father offspring when mated to uninfected females. because ci can dramatically affect fitness in natural populations, mechanisms that abate ci can have equally large impacts on fitness. we have discovered that repeated copulation by wolbachia-infected male ... | 1998 | 9523438 |
| conservation of locus-specific microsatellite variability across species: a comparison of two drosophila sibling species, d. melanogaster and d. simulans. | fifteen microsatellite loci were studied in drosophila melanogaster and drosophila simulans, two closely related sibling species which split 2-3.5 mya. within-species variances in repeat number were found to differ up to 1,000-fold among individual microsatellite loci. a significant correlation of log variances between both species indicated a locus-specific mutation rate of microsatellites. hence, locus-specific effects are apparently among the major forces influencing microsatellite variation ... | 1998 | 9491614 |
| inheritance mode of drosophila simulans female mating propensity with d. melanogaster males. | the genetic factors involved in the sexual isolation between drosophila simulans females and d. melanogaster males are hardly known. we present a study of female mating propensity of d. simulans from different geographic origins with d. melanogaster males. our results reveal the existence of genetic variability in d. simulans for this trait. female discrimination is dominant against high female interspecific mating, which differs from that detected in other drosophila species crosses. | 2006 | 9487683 |
| genetics of hybridization between drosophila simulans females and d. melanogaster males. | drosophila simulans and d. melanogaster are sibling cosmopolitan species with imperfect ethological isolation. hybridization is easy between d. melanogaster females and d. simulans males, but the reciprocal cross has been traditionally considered as very scarce and little is known about the environmental and genetic factors that affect it. we used classical genetic analyses to determine the influence of each major chromosome on the breakdown of sexual isolation between females of d. simulans and ... | 1998 | 9474773 |
| codon bias evolution in drosophila. population genetics of mutation-selection drift. | although non-random patterns of synonymous codon usage are a prominent feature in the genomes of many organisms, the relatives roles of mutational biases and natural selection in maintaining codon bias remain a contentious issue. in some species, patterns of codon bias and empirical findings on the biology of translation suggest 'major codon preference', a balance among mutation pressure, genetic drift, and weak selection in favor of translationally superior codons. population genetics theory ma ... | 1997 | 9461401 |
| nonrandom partition of mitochondria in heteroplasmic drosophila. | in order to understand the status of heteroplasmy and its evolution within the drosophila melanogaster subgroup, cytoplasm microinjections between eggs were performed involving three lineages of drosophila simulans, carrying the sii, siii or siiii mtdna type, respectively, and two strains of drosophila mauritiana carrying the mai or maii mtdna type. progeny of eggs from all combinations of injection were analysed. the maii or sii molecules, when provided by the donor, were never detected in the ... | 1997 | 9418268 |
| the sex-ratio trait in drosophila simulans: genetic analysis of distortion and suppression. | the sex-ratio trait described in several drosophila species is a type of naturally occurring x-linked meiotic drive that causes males bearing a sex-ratio x chromosome to produce progenies with a large excess of females. we have previously reported the occurrence of sex-ratio x chromosomes in drosophila simulans. in this species, because of the co-occurrence of drive suppressors, the natural populations and the derived laboratory strains show an equal sex-ratio even when sex-ratio x chromosomes a ... | 1997 | 9335600 |
| infection of the gonads of the simes strain of drosophila simulans by the hereditary reovirus dsv. | the s character of drosophila simulans simes-st strain undergoes a non-mendelian transmission. it has been postulated that a virus, drosophila s virus (dsv), could be the causative agent. electron microscopy analysis of gonads of flies showing a strong s phenotype revealed the presence of virus in or near the germ cells. the s character transmission rate is greater in females than that in males. similarly, the level of infection by dsv is higher in ovaries than that in testes. flies treated at a ... | 1997 | 9281403 |
| chromosomal distribution of the 412 retrotransposon in natural populations of drosophila simulans. | the insertion site localization of the 412 retrotransposable element was analysed by in situ hybridization to the polytene chromosomes of 57 individual genomes from 25 natural populations of drosophila simulans. the 412 insertion sites along the chromosomes show a tendency to aggregate in the distal and proximal ends of the 2r arm, and in several local regions along the 3r arm. the distribution of the 412 insertion sites, weighted by dna content, along the chromosome arms reveals an overall tend ... | 1997 | 9279009 |
| nucleotide sequence divergence in the a+t-rich region of mitochondrial dna in drosophila simulans and drosophila mauritiana. | we have determined the nucleotide sequences of two regions within the a+t-rich region of mitochondrial dna (mtdna) in the siiii type of drosophila simulans and the mai type of d. mauritiana. the sequences of the two regions in siiii and mai are almost identical. the sequences include elements corresponding to the type i and type ii repeats elements and the t-stretches as reported in d. melanogaster; an approximately 340-bp region (a region) adjacent to the trna(ile) gene includes a part of the t ... | 1997 | 9254919 |
| genetic basis of sperm and testis length differences and epistatic effect on hybrid inviability and sperm motility between drosophila simulans and d. sechellia. | results are reported from a genetic study of hybrid inviability and three 'fertilization traits' (sperm motility and length, and testis size) that affect hybrid sterility between the sibling species drosophila simulans and d. sechellia. the main findings are as follows. (i) for sperm length there was a dominant effect of the d. simulans genome over that of d. sechellia, and the y chromosome of d. sechellia in the background of d. simulans reduced the sperm length. (ii) in contrast, testis length ... | 1997 | 9134705 |
| an introgression analysis of quantitative trait loci that contribute to a morphological difference between drosophila simulans and d. mauritiana. | drosophila simulans and d. mauritiana differ markedly in morphology of the posterior lobe, a male-specific genitalic structure. both size and shape of the lobe can be quantified by a morphometric variable, pcl, derived from principal components and fourier analyses. the genetic architecture of the species difference in pcl was investigated previously by composite interval mapping, which revealed largely additive inheritance, with a minimum of eight quantitative trait loci (qtl) affecting the tra ... | 1997 | 9071588 |
| genetics of sexual isolation in male hybrids of drosophila simulans and d. mauritiana. | sexual isolation between the sibling species d. simulans and d. mauritiana is due largely to the rejection of d. simulans males by d. mauritiana females. genetic analysis shows that genes on the x and third chromosomes contribute to the differences between males causing sexual isolation, while the y chromosome, second chromosome and cytoplasm have no effect. these chromosome effects differ from those observed in a previous analysis of sexual isolation in hybrid females, implying that different g ... | 1996 | 9062078 |
| wolbachia-induced delay of paternal chromatin condensation does not prevent maternal chromosomes from entering anaphase in incompatible crosses of drosophila simulans. | the behavior of parental chromosomes during the first mitosis of drosophila simulans zygotes obtained from unidirectional incompatible crosses is described and it is demonstrated that the condensation of parental chromatin complements was asynchronous. the timing of paternal chromatin condensation appeared to be delayed in these embryos, so that condensed maternal chromosomes and entangled prophase-like paternal fibers congressed in the equatorial plane of the first metaphase spindle. at anaphas ... | 1997 | 9044057 |
| transposition rate of the 412 retrotransposable element is independent of copy number in natural populations of drosophila simulans. | the transposition and excision rates of the 412 retrotransposable element were estimated in five populations of drosophila simulans differing in their average 412 copy numbers, which ranged from 2 to 54. the transposition rate was found to equal 1 x 10(-3) to 2 x 10(-3), independently of copy number. no excision was detected. these values eliminate autoregulation as a force maintaining copy number of the 412 element in natural populations of d. simulans. | 1997 | 9029796 |
| conceptual translation of timeless reveals alternative initiating methionines in drosophila. | we have sequenced genomic fragments which encode the n-terminus of the timeless (tim) clock protein in drosophila simulans and d. yakuba. we observe that in these two species, the initiating methionine appears to lie downstream of the one proposed to encode the translational start ind.melanogaster, thereby truncating the n-terminus by 23 amino acids. we then sequenced the corresponding 5'fragment in a number of d. melanogaster individuals from different strains. we observed a polymorphism which ... | 1997 | 9016581 |
| reduced variation in drosophila simulans mitochondrial dna. | we investigated the evolutionary dynamics of infection of a drosophila simulans population by a maternally inherited insect bacterial parasite, wolbachia, by analyzing nucleotide variability in three regions of the mitochondrial genome in four infected and 35 uninfected lines. mitochondrial variability is significantly reduced compared to a noncoding region of a nuclear-encoded gene in both uninfected and pooled samples of flies, indicating a sweep of genetic variation. the selective sweep of mi ... | 1996 | 8978041 |
| somatic activity of the mariner transposable element in natural populations of drosophila simulans. | the characteristics of the mariner transposable element in natural populations of drosophila simulans from different parts of the world were analysed. the somatic excision rate (estimated from a test-cross with a reference strain), the average number of copies (determined by southern blots), and the presence of deleted copies (detected by polymerase chain reaction amplification) were estimated for each population. there was a great variability in the somatic excision rate, measured as the percen ... | 1996 | 8952091 |
| population genetics of silent and replacement variation in drosophila simulans and d. melanogaster: x/autosome differences? | 1996 | 8952085 | |
| molecular structure of the transposable element ninja in drosophila simulans. | genetically unstable dna sequences of 16.1 kb in length were isolated from the white locus of the w(mky) strain of drosophila simulans. this insertional dna has some unique characteristics as a transposon. it is found in high numbers in this strain and its revertant strains w(psm1) and w(cho), but not elsewhere, and the sequence is a tandem triplication of a basic repeating unit. in order to determine the structure of the insert as whole and the functional unit as a transposon, we analyzed nine ... | 1996 | 8925473 |
| discord between the phylogenies inferred from molecular versus functional data: uneven rates of functional evolution or low levels of gene flow? | according to measures of molecular divergence, the three species of the drosophila simulans clade are closely related to and essentially equidistant from each other. we introgressed 10% of the d. sechellia x chromosome into a pure d. simulans genetic background and found that males carrying this introgressed region were consistently fertile; in contrast, males carrying the same segment from d. mauritiana are sterile and suffer from incompatibilities at a minimum of four loci. together with other ... | 1996 | 8913771 |
| high nucleotide sequence variation in a region of low recombination in drosophila simulans is consistent with the background selection model. | we surveyed nucleotide sequence variation at glucose dehydrogenase (gld), in a region of low recombination on chromosome 3r, from a population sample of drosophila simulans. the levels of nucleotide variation were surprisingly high. there was no departure from the expectation of a neutral model for the level of polymorphism, indicating no evidence of a selective sweep in this region. there was a significant deficiency of singleton polymorphisms according to the fu and li test, although tajima an ... | 1996 | 8865667 |
| a molecular taxonomy for cricket paralysis virus including two new isolates from australian populations of drosophila (diptera: drosophilidae). | two new isolates of cricket paralysis virus, tar and sim, are described that were originally isolated from laboratory colonies of drosophila melanogaster and drosophila simulans respectively. using a combination of biological, serological and molecular characters it was possible to distinguish the sim isolate from all other isolates and it is thus described as a new strain; crpvsim. the tar isolate however, was indistinguishable from the crpv reference isolate crpvvic/gm/d2(2)/gm/d2(2) (teleogry ... | 1996 | 8856030 |
| a genome-wide survey of hybrid incompatibility factors by the introgression of marked segments of drosophila mauritiana chromosomes into drosophila simulans. | in hybrids between drosophila simulans and d. mauritiana, males are sterile and females are fertile, in compliance with haldane's rule. the genetic basis of this phenomenon was investigated by introgression of segments of the mauritiana genome into a simulans background. a total of 87 positions throughout the mauritiana genome were marked with p-element insertions and replicate introgressions were made by repeated backcrossing to simulans for 15 generations. the fraction of hemizgyous x chromoso ... | 1996 | 8849890 |
| genetic analysis of a morphological shape difference in the male genitalia of drosophila simulans and d. mauritiana. | two closely related species of drosophila, d. simulans and d. mauritiana, differ markedly in morphology of the posterior lobe of the male genital arch. both size and shape aspects of lobe variation can be quantified by a morphometric descriptor based on elliptical fourier and principal components analyses. the genetic architecture of this quantitative trait (pc1) was investigated by hybridizing inbred lines to produce two backcross populations approximately 200 individuals each, which were analy ... | 1996 | 8846893 |
| genetics of a difference in male cuticular hydrocarbons between two sibling species, drosophila simulans and d. sechellia. | in seven of the eight species of the drosophila melanogaster group, the predominant cuticular hydrocarbon of males is 7-tricosene, but in the island endemic species d. sechellia it is 6-tricosene. the phylogeny of the group implies that the novel hydrocarbon profile of d. sechellia is a derived character. genetic analysis of hybrids between d. sechellia and its close relative d. simulans show that each of the five major chromosome arms carries at least one gene affecting the ratio of the two tri ... | 1996 | 8844156 |
| cytological analysis of fertilization and early embryonic development in incompatible crosses of drosophila simulans. | cytoplasmic incompatibility (ci) is a unique form of male sterility found in numerous insect species that harbor a bacterial endosymbiont wolbachia. ci is characterized by severe reduction in the progeny produced when infected males are crossed to uninfected females. the reduction in progeny correlates with developmental defects that arise during and immediately following fertilization, suggesting that sperm function is disrupted. to investigate the nature of the cellular defects associated with ... | 1996 | 8817452 |
| the genetics of reproductive isolation in the drosophila simulans clade: x vs. autosomal effects and male vs. female effects. | a strong effect of homozygous autosomal regions on reproductive isolation was found for crosses between the species in the drosophila simulans clade. second chromosome regions were introgressed from d. mauritiana and d. sechellia into d. simulans and tested for their homozygous effects on hybrid male and hybrid female sterility and inviability. most introgressions are fertile as heterozygotes, yet produce sterile male offspring when made homozygous. the density of homozygous autosomal factors co ... | 1996 | 8807297 |
| evolutionary changes in the expression pattern of a developmentally essential gene in three drosophila species. | the hypothesis that morphological evolution may largely result from changes in gene regulation rather than gene structure has been difficult to test. morphological differences among insects are often apparent in the cuticle structures produced. the dopa decarboxylase (ddc) and alpha-methyldopa hypersensitive (amd) genes arose from an ancient gene duplication. in drosophila, they have evolved nonoverlapping functions, including the production of distinct types of cuticle, and for ddc, the product ... | 1996 | 8692952 |
| naturally occurring variation in copia expression is due to both element (cis) and host (trans) regulatory variation. | significant differences in levels of copia [drosophila long terminal repeat (ltr) retrotransposon] expression exist among six species representing the drosophila melanogaster species complex (d. melanogaster, drosophila mauritiana, drosophila simulans, drosophila sechellia, drosophila yakuba, and drosophila erecta) and a more distantly related species (drosophila willistoni). these differences in expression are correlated with major size variation mapping to putative regulatory regions of the co ... | 1996 | 8692951 |
| the relationship between structural variation and dysgenic properties of p elements in long-established p-transformed lines of drosophila simulans. | ten lines of drosophila simulans were investigated with respect to p activity, p susceptibility and the number and structure of their p copies, eight years after transformation with the p element. all 10 were found to have reached a steady state. they exhibited varying levels of p activity (from 0 per cent to 96 per cent gd sterility) and, with the exception of one line, were not p-susceptible. in contrast with p element behaviour in d. melanogaster: (i) no relationship was found between the mol ... | 1996 | 8682694 |
| geographical variation in insertion site number of retrotransposon 412 in drosophila simulans. | the insertion site number of the retrotransposable element 412 was analyzed in natural populations of drosophila simulans of worldwide origin by in situ hybridization. we observe a gradient in copy number ranging from as high as 23 in europe to 1-10 in south africa, while populations in madagascar and the indian islands, which are the cradle of d. simulans, have only 3-7 copies. we find very different copy numbers in some local populations of australia and the pacific islands (with around 60 cop ... | 1996 | 8642613 |
| haplotype test reveals departure from neutrality in a segment of the white gene of drosophila melanogaster. | restriction map studies previously revealed extensive linkage disequilibria in the transcriptional unit of the white locus in natural drosophila melanogaster populations. to understand the causes of these disequilibria, we sequenced a 4722-bp region of the white gene from 15 lines of d. melanogaster and 1 line of drosophila simulans. statistical tests applied to the entire 4722-bp region do not reject neutrality. in contrast, a test for high-frequency haplotypes ("haplotype test") revealed an 83 ... | 1995 | 8601488 |
| wolbachia superinfections and the expression of cytoplasmic incompatibility. | strains of drosophila simulans from riverside, california (dsr) and hawaii (dsh) harbour distinct strains of the cytoplasmic incompatibility microorganism wolbachia, resulting in the expression of bidirectional incompatibility when crossed. d. simulans lines carrying both of these (superinfected) wolbachia strains were generated by the transfer of infected dsh cytoplasm into dsr embryos by microinjection. the superinfected flies were unidirectionally incompatible with both dsr and dsh individual ... | 1995 | 8587875 |
| variability within the seychelles cytoplasmic incompatibility system in drosophila simulans. | in drosophila simulans, we described a cytoplasmic incompatibility (ci) system (seychelles) restricted to insular populations that harbor the mitochondrial type sii. since then, these populations have been shown to be heterogeneous, some being infected by one wolbachia genetic variant only (wha), while others are infected simultaneously by wha and by another variant (wno) always found in association with wha. we have experimentally obtained two d. simulans strains only infected by the wno varian ... | 1995 | 8582608 |
| naturally-occurring wolbachia infection in drosophila simulans that does not cause cytoplasmic incompatibility. | microbes of the genus wolbachia are transmitted by their hosts via the maternal parent and are responsible for cytoplasmic incompatibility among insect populations. this phenomenon can result in wolbachia spreading through natural populations as previously demonstrated in drosophila simulans. here we describe another wolbachia infection in d. simulans that does not cause cytoplasmic incompatibility. this is a property of the wolbachia rather than the nuclear background. the infection occurs at a ... | 1996 | 8575931 |
| indirect evidence of alteration in the expression of the rdna genes in interspecific hybrids between drosophila melanogaster and drosophila simulans. | crosses between drosophila melanogaster females and d. simulans males produce viable hybrid females, while males are lethal. these males are rescued if they carry the d. simulans lhr gene. this paper reports that females of the wild-type d. melanogaster population staket do not produce viable hybrid males when crossed with d. simulans lhr males, a phenomenon which we designate as the staket phenotype. the agent responsible for this phenomenon was found to be the staket x chromosome (xmel, stk). ... | 1996 | 8569692 |
| nucleotide polymorphism in the 5' promoter region of esterase 6 in drosophila melanogaster and its relationship to enzyme activity variation. | a 974-bp region immediately 5' of the esterase 6 gene was sequenced in 17 field derived third chromosome isoallelic lines. twenty-three polymorphisms were identified, only two in the first 400 bp 5' but 16 in a 325-bp region from -494 to -819 bp. this distribution differs from previously published patterns in drosophila simulans and d. mauritiana, where the first 800 bp are highly conserved. fourteen common polymorphisms in the 325-bp region above are all in strong linkage disequilibrium with ea ... | 1995 | 8536969 |
| evolutionary dynamics of the enhancer region of even-skipped in drosophila. | we report findings on naturally occurring variation in the regulatory region of even-skipped in drosophila. this pair-rule gene encodes a homeobox-containing transcription factor, is expressed as a series of seven transverse stripes in developing embryos, and defines parasegmental boundaries. the 5' flanking region of the gene contains a 671-bp enhancer governing stripe 2 expression. the stripe 2 enhancer contains multiple binding sites for four transcription factors that provide positional info ... | 1995 | 8524036 |
| the distribution of the transposable element bari-1 in the drosophila melanogaster and drosophila simulans genomes. | the distribution of the transposable element bari-1 in d. melanogaster and d. simulans was examined by southern blot analysis and by in situ hybridization in a large number of strains of different geographical origins and established at different times. bari-1 copies mostly homogeneous in size and physical map are detected in all strains tested. both in d. melanogaster and in d. simulans a relatively high level of intraspecific insertion site polymorphism is detectable, suggesting that in both s ... | 1995 | 8522166 |
| the distribution of transposable elements on x chromosomes from a natural population of drosophila simulans. | the distribution of 13 transposable element families along 15 x chromosomes from an african natural population of drosophila simulans was determined by in situ hybridization to polytene chromosomes. the transposable elements cloned from drosophila melanogaster all hybridized with drosophila simulans chromosomes. the number of copies per family was 3.5 times lower in the latter species and correlated with the copy number per family in drosophila melanogaster. with the exception of 297, the copy n ... | 1995 | 8522157 |
| genetics of reproductive isolation in the drosophila simulans clade: dna marker-assisted mapping and characterization of a hybrid-male sterility gene, odysseus (ods). | in this study, we address the question of whether there exist major genes that cause complete male sterility in the interspecific hybrids of drosophila and, if they do, how these genes may be characterized at the molecular level. our approach is to introgress small segments of the x chromosome from drosophila mauritiana (or drosophila sechellia) into drosophila simulans by repeated backcrosses for more than 20 generations. the introgressions are monitored by both visible mutations and a series o ... | 1993 | 8514135 |
| the genetic basis of haldane's rule and the nature of asymmetric hybrid male sterility among drosophila simulans, drosophila mauritiana and drosophila sechellia. | haldane's rule (i.e., the preferential hybrid sterility and inviability of heterogametic sex) has been known for 70 years, but its genetic basis, which is crucial to the understanding of the process of species formation, remains unclear. in the present study, we have investigated the genetic basis of hybrid male sterility using drosophila simulans, drosophila mauritiana and drosophila sechellia. an introgression of d. sechellia y chromosome into a fairly homogenous background of d. simulans did ... | 1993 | 8514134 |
| interspecific and intraspecific horizontal transfer of wolbachia in drosophila. | cytoplasmic incompatibility (ci) in drosophila simulans is related to infection of the germ line by a rickettsial endosymbiont (genus wolbachia). wolbachia were transferred by microinjection of egg cytoplasm into uninfected eggs of both d. simulans and d. melanogaster to generate infected populations. transinfected strains of d. melanogaster with lower densities of wolbachia than the naturally infected d. simulans strain did not express high levels of ci. however, transinfected d. melanogaster e ... | 1993 | 8511587 |
| genetic control of pheromones in drosophila simulans. ii. kété, a locus on the x chromosome. | the production of drosophila cuticular hydrocarbons, including contact pheromones, is under polygenic control. to investigate x-linked loci, ems mutations were induced in drosophila simulans flies. a mutant strain was discovered which in both sexes show a reduction in the biosynthesis of both 7-tricosene (7-t) the species contact pheromone and all other linear hydrocarbons. the locus controlling this effect, kété, is recessive and was localized to i, 18.5. unlike a previously identified gene on ... | 1993 | 8454203 |