Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| the spontaneous mutation rate in drosophila simulans. | the purpose of this investigation was to determine whether there exists a correlation in drosophila between the spontaneous mutation rate and the amount of dispersed middle repetitive (mobile) dna sequences. the amount of these sequences is 7 times less in drosophila simulans as compared to drosophila melanogaster. therefore, if a correlation exists, the spontaneous mutation rate in drosophila simulans should be 7 times lower than that in drosophila melanogaster. we isolated an x-chromosome inve ... | 1987 | 2825010 |
| drosophila simulans cu-zn superoxide dismutase gene sequence. | 1989 | 2780301 | |
| genetics of sexual isolation between two sibling species, drosophila simulans and drosophila mauritiana. | drosophila simulans and drosophila mauritiana are sibling species that show substantial sexual isolation in one of their two reciprocal hybridizations. genetic analysis reveals that in females this isolation is caused by at least one recessive gene on each autosome, while the x chromosome has little or no effect. our results, combined with those of previous studies, show that in drosophila the genetics of sexual isolation differs from that of postzygotic reproductive isolation, which invariably ... | 1989 | 2748596 |
| genetic analysis of x-linked sterility in hybrids between three sibling species of drosophila. | three morphological markers (yellow, miniature, and forked) are used to map the location of x-chromosome segments causing male sterility in drosophila simulans/d. mauritiana and d. simulans/d. sechellia hybrids. in both hybridizations at least three sections of the chromosome contain genes with substantial effects on sterility. this represents the maximum genetic divergence detectable with the three markers, suggesting that the x chromosome contains many loci affecting postzygotic reproductive i ... | 1989 | 2732092 |
| hybrid dysgenesis in drosophila simulans lines transformed with autonomous p elements. | the molecular and phenotypic analysis of several previously described p element-transformed lines of drosophila simulans was extended in order to determine whether they had the potential to produce a syndrome of p-m hybrid dysgenesis analogous to the one in drosophila melanogaster. the transformed line with the highest number of p elements at the beginning of the analysis, dsp pi-5c, developed strong p activity potential and p element regulation, properties characteristic of d. melanogaster p st ... | 1989 | 2731724 |
| the generation of transplasmic drosophila simulans by cytoplasmic injection: effects of segregation and selection on the perpetuation of mitochondrial dna heteroplasmy. | experimental transplasmic drosophila simulans were obtained through cytoplasm microinjection between eggs carrying different mitochondrial genomes. these genomes (siii and siiii) show a 1.5% difference in their sequences. they produced a large number of heteroplasmic flies in their f1 progeny and several flies were still heteroplasmic at the eighth generation. the distribution of frequencies of mitochondrial genotypes in the offspring of heteroplasmic females suggests that the stochastic process ... | 1989 | 2608025 |
| nucleolar dominance and replicative dominance in drosophila interspecific hybrids. | the replication of the rdna complement of only one nucleolus organizer region during polytene chromosome formation (replicative dominance) was initially observed in drosophila melanogaster. here we demonstrate replicative dominance in drosophila simulans and d. melanogaster/d. simulans interspecific hybrids. a second nucleolar phenomenon, nucleolar dominance, is observed in the diploid tissue of interspecific hybrids. in this case only one of two nucleolus organizer regions forms a nucleolus. ho ... | 1989 | 2511070 |
| does postzygotic isolation result from improper dosage compensation? | the x chromosome invariably has the largest effect on postzygotic isolation between animal species. one explanation of this pattern is that inviability and sterility result from a breakdown in the dosage compensation of x-linked genes in hybrids. in drosophila, such breakdown could result from divergence of the genes used to assess the x/autosomal (x/a) ratio, and thus the sex, of an individual. i test this hypothesis by introducing mutant alleles of the sex-lethal locus into drosophila melanoga ... | 1989 | 2503427 |
| nucleotide variation and divergence in the histone multigene family in drosophila melanogaster. | nucleotide differences in the histone h3 gene family in drosophila melanogaster were studied on three levels: (1) within a chromosome, (2) within a population and (3) between species (d. melanogaster and drosophila simulans). the average difference within the h3 gene within a chromosome was 0.0040 per nucleotide site, about 52% of that within a population (0.0077). the proportion of divergent sites between the two species was 0.0575, which is about 8.5 times the difference within a species. the ... | 1989 | 2499516 |
| an unusual y chromosome of drosophila simulans carrying amplified rdna spacer without rrna genes. | the x and y chromosomes of drosophila melanogaster each contain a cluster of several hundred ribosomal rna genes (rdna). a nontranscribed spacer region separates adjacent rrna genes and contains tandem copies of 240 bp repeats that include the initiation site for rna polymerase i transcription. we show here that drosophila simulans, a sibling species of d. melanogaster, contains few, if any, rrna genes on its y chromosome but carries instead a large block (3,000 kb or 12,500 copies) of 240 bp no ... | 1990 | 2379820 |
| incomplete maternal transmission of mitochondrial dna in drosophila. | the possibility of incomplete maternal transmission of mitochondrial dna (mtdna) in drosophila, previously suggested by the presence of heteroplasmy, was examined by intra- and interspecific backcrosses of drosophila simulans and its closest relative, drosophila mauritiana. mtdnas of offspring in these crosses were characterized by southern hybridization with two alpha-32p-labeled probes that are specific to paternal mtdnas. this method could detect as little as 0.03% paternal mtdna, if present, ... | 2006 | 2249764 |
| bidirectional incompatibility between conspecific populations of drosophila simulans. | cytoplasmic incompatibility (ci) describes the phenomenon whereby eggs fertilized by sperm from insects infected with a rickettsial endosymbiont fail to hatch. unidirectional ci between conspecific populations of insects is a well documented phenomenon. bidirectional ci has, however, only been described in mosquito populations, and recently between closely related species of parasitic wasps, where it is of interest as both an unusual form of reproductive isolation and as a potential means of ins ... | 1990 | 2234083 |
| genetic basis of the difference in alcohol dehydrogenase expression between drosophila melanogaster and drosophila simulans. | drosophila melanogaster and its sibling species, drosophila simulans, differ in expression of the enzyme alcohol dehydrogenase (adh). adult melanogaster flies that are homozygous for the slow allozyme have approximately twice the level of adh activity and crossreacting material as simulans adults. there is no corresponding difference in adh mrna, however, so this difference in adh protein level is evidently due to a difference in the rate of translation of the two rnas and/or to a difference in ... | 1990 | 2124699 |
| evolution of drosophila mitochondrial dna and the history of the melanogaster subgroup. | the nucleotide sequences of a common region of 15 mitochondrial dnas (mtdnas) sampled from the drosophila melanogaster subgroup were determined. the region is 2527 base pairs long, including most of the nadh dehydrogenase subunit 2 and cytochrome oxidase subunit 1 genes punctuated by three trna genes. the comparative study revealed (i) the extremely low saturation level of transitional differences, (ii) recombination or variable substitution rates even within species, (iii) long persistence time ... | 1990 | 2124697 |
| rapid evolution in a fraction of the drosophila nuclear genome. | previous observations have indicated that drosophila dna contains a component that evolves so rapidly that it fails to hybridize between the dnas of sibling species. to establish the reality of this component and study its properties, the fraction (about 20%) of drosophila simulans (dsim) dna that fails to hybridize to drosophila melanogaster (dmel) dna has been isolated. the majority of the hybridizable part of this isolated fraction (based on control tests on dsim dna) fails to hybridize with ... | 1990 | 2109090 |
| factors affecting the distribution of cytoplasmic incompatibility in drosophila simulans. | in drosophila simulans a wolbachia-like microorganism is responsible for reduced egg-hatch when infected males mate with uninfected females. both incompatibility types have previously been found in north america, europe and africa. some california populations have remained polymorphic for over two years, and the infection is apparently spreading in central california. egg hatch proportions for wild-caught females from polymorphic populations show that the incompatibility system acts in nature, b ... | 1990 | 2076821 |
| genetic control of pheromones in drosophila simulans. i. ngbo, a locus on the second chromosome. | 7-tricosene and 7-pentacosene are predominant hydrocarbons on the cuticle of both sexes in drosophila simulans. the pheromonal role of 7-tricosene has been clearly established for conspecific males, while a synergistic effect for 7-pentacosene has been postulated. interstrain variation for the production of both compounds is very marked, but similar for both sexes. the genetic basis of this polymorphism was investigated. a major role was found for the second chromosome, which controls the 7-tric ... | 1991 | 2071017 |
| mitochondrial dna heteroplasmy maintained in natural populations of drosophila simulans in réunion. | mitochondrial dna (mtdna) variation in drosophila simulans was studied to determine whether the cytoplasmic state of mtdna heteroplasmy persists in natural populations in réunion. for this purpose, 172 isofemale lines, newly collected from two local populations, were examined, among which three types of mtdna (siii, siiii and siiii') were found, based on the hpa ii restriction pattern. ten of the lines were heteroplasmic for a combination of siii and siiii, as determined by autoradiography. the ... | 1991 | 2055455 |
| the effect of heteroplasmy on cytoplasmic incompatibility in transplasmic lines of drosophila simulans showing a complete replacement of the mitochondrial dna. | unidirectional cytoplasmic incompatibility has been observed in crosses between different strains of drosophila simulans when the males, but not the females, involved in the crosses are infected with intracellular rickettsia-like microorganisms. in contrast to what is known about this system an unexpected partial incompatibility has been observed between two infected strains. transplasmic lines have been constructed in the laboratory to investigate this phenomenon. the injection of a foreign inf ... | 1991 | 2010316 |
| molecular evolution of drosophila metallothionein genes. | the metallothionein genes of drosophila melanogaster, mtn and mto, may play an important role in heavy metal detoxification. several different tandem duplications of mtn have been shown to increase cadmium and copper tolerance, as well as mtn expression. in order to investigate the possibility of increased selection for duplications of these genes in natural populations exposed to high levels of heavy metals, we compared the frequencies of such duplications among flies collected from metal-conta ... | 1990 | 1981765 |
| seasonal change in metabolic rate of drosophila simulans. | 1. second-generation descendents of wild-caught female drosophila simulans sturtevant collected at different seasons from gainesville, florida, usa, were reared under a constant temperature and food level but with seasonally variable photoperiods. 2. body weight and metabolic rate, after adjustment to a common body weight, were higher in descendents of flies collected in fall and winter. 3. temperature sensitivity (q10) of metabolic rate was also related to season: higher q10 values were associa ... | 1990 | 1981031 |
| active mariner transposable elements are widespread in natural populations of drosophila simulans. | the occurrence of active, or autonomous, mariner elements was investigated by crossing white-peach mutant drosophila simulans females with wild-type males from various geographic origins. from a total of 194 experimental crosses only 17 failed to produce progeny with eye mosaicism (mos, i.e. pigmented spots in otherwise white-peach eyes). therefore, active mariner elements inducing somatic excision of the copy inserted at the white locus are abundant in all populations sampled. in the experiment ... | 1990 | 1980741 |
| is there selection on rflp differences in mitochondrial dna? | experimental populations of drosophila simulans were established for the purpose of detecting the presence or absence of selection on a restriction fragment length polymorphism in mitochondrial dna (mtdna). it was then discovered that the founding strains differed with respect to the rickettsia-mediated incompatibility system in this species, which is maternally transmitted together with the mtdna differences. a population model was constructed using the known fitness effects of the incompatibil ... | 1990 | 1974225 |
| alfred henry sturtevant and crosses between drosophila melanogaster and drosophila simulans. | 1991 | 1936952 | |
| host-plant specialization in the drosophila melanogaster species complex: a physiological, behavioral, and genetical analysis. | drosophila sechellia, endemic to the seychelles, breeds in a single resource, morinda citrifolia, whereas its close sympatric relative, drosophila simulans, is a cosmopolitan generalist breeding in a great variety of resources. the effects of morinda on various fitness traits of these two species, their f1 hybrids, and reciprocal backcrosses were analyzed. morinda fruit is highly toxic to drosophila species, except d. sechellia. the toxicity is expressed in adults, embryos, and larvae. in embryo ... | 1991 | 1900368 |
| molecular transfer of a species-specific behavior from drosophila simulans to drosophila melanogaster. | drosophila males modulate the interpulse intervals produced during their courtship songs. these song cycles, which are altered by mutations in the clock gene period, exhibit a species-specific variation that facilitates mating. we have used chimeric period gene constructs from drosophila melanogaster and drosophila simulans in germline transformation experiments to map the genetic control of their song rhythm difference to a small segment of the amino acid encoding information within this gene. | 1991 | 1900131 |
| rapid spread of an inherited incompatibility factor in california drosophila. | in drosophila simulans in california, an inherited cytoplasmic incompatibility factor reduces egg hatch when infected males mate with uninfected females. the infection is spreading at a rate of more than 100 km per year; populations in which the infection was rare have become almost completely infected within three years. analyses of the spread using estimates of selection in the field suggest dispersal distances far higher than those found by direct observation of flies. hence, occasional long- ... | 1991 | 1896086 |
| [a mutant strain of drosophila simulans sensitive to the toxic and mutagenic action of benz(a)pyrene]. | a 364 yv strain sensitive to the toxic effect of benzo(a)pyrene (bp) was identified among 49 mutant strains of drosophila simulans. heterozygotes female 364 x male turku obtained by crossing 364 yv species with those of wild bp-resistant turku strain were more sensitive than female turku x male 364 heterozygotes to both toxic and mutagenic effects of the carcinogen in the test of induction of somatic mosaicism with the yellow marker. non-carcinogenic pyrene appeared weekly toxic and non-mutageni ... | 1991 | 1842655 |
| cytoplasmic incompatibility in drosophila populations: influence of assortative mating on symbiont distribution. | cytoplasmic incompatibility is known to occur between strains of both drosophila simulans and d. melanogaster. incompatibility is associated with the infection of drosophila with microorganismal endosymbionts. this paper reports survey work conducted on strains of d. simulans and d. melanogaster from diverse geographical locations finding that infected populations are relatively rare and scattered in their distribution. the distribution of infected populations of d. simulans appears to be at odd ... | 1991 | 1787328 |
| [benzo(a)pyrene pretreatment of drosophila simulans mutant strain results in the induction of aberrant isoform of cytochrome p-450 with increased capacity to metabolize benzo(a)pyrene]. | the basal level of benzo(a)pyrene monooxygenase, epoxide hydrolase and glutathione s-transferase activity as well as the content of cytochrome p-450 were found the same in both compared benzo(a)pyrene (bp) sensitive d. simulans strain 364yv and bp-resistant wild one (turku). phenobarbital pretreatment resulted in the same increase level of these enzyme activities in both strains. bp-pretreatment of 364yv flies decreased the amount of the cytochrome p-450 but raised up the turnover of bp per mole ... | 1991 | 1786390 |
| developmental stability in hybrids between the sibling species pair, drosophila melanogaster and drosophila simulans. | drosophila melanogaster and its sibling species d.simulans were hybridized in the laboratory to test the hypothesis that developmental homeostasis in hybrids between two species having no prior gene flow would be significantly reduced. developmental stability was assessed by measuring fluctuating asymmetry for three bilateral traits: sternopleural chaetae, wing length, and fronto-orbital plus frontal chaetae. male f1 hybrids showed no decrease in developmental stability compared to males of pare ... | 1991 | 1756963 |
| geographic distribution and inheritance of three cytoplasmic incompatibility types in drosophila simulans. | wolbachia-like microorganisms have been implicated in unidirectional cytoplasmic incompatibility between strains of drosophila simulans. reduced egg eclosion occurs when females from uninfected strains (type w) are crossed with males from infected strains (type r). here we characterize a third incompatibility type (type s) which is also correlated with the presence of wolbachia-like microorganisms. despite the fact that the symbionts cannot be morphologically distinguished, we observed complete ... | 1991 | 1743484 |
| copia expression is variable among natural populations of drosophila. | a survey of copia (retroviral-like element) expression in flies representing 37 populations worldwide of drosophila melanogaster, drosophila simulans and drosophila mauritiana demonstrates that, although copia elements are present in all three species, copia-encoded transcripts are detectable only in d. melanogaster. levels of copia transcripts vary nearly 100-fold among flies representing geographically diverse populations of d. melanogaster and this variation is not correlated with variability ... | 1970 | 1700962 |
| lack of polymorphism on the drosophila fourth chromosome resulting from selection. | evolutionary processes can be inferred from comparisons of intraspecific polymorphism and interspecific divergence. we sequenced a 1.1-kb fragment of the cubitus interruptus dominant (cid) locus located on the nonrecombining fourth chromosome for ten natural lines of drosophila melanogaster and nine of drosophila simulans. we found no polymorphism within d. melanogaster and a single polymorphism within d. simulans; divergence between the species was about 5%. comparison with the alcohol dehydrog ... | 1991 | 1686006 |
| molecular population genetics of the distal portion of the x chromosome in drosophila: evidence for genetic hitchhiking of the yellow-achaete region. | we have estimated dna sequence variation and differentiation within and between drosophila melanogaster and its sibling species, drosophila simulans, using six-cutter restriction site variation at yellow-achaete (y-ac), phosphogluconate dehydrogenase (pgd), and period (per). these three gene regions are of varying distance from the telomere of the x chromosome and range from very low to moderate rates of recombination in d. melanogaster. according to tajima's test of neutrality, the pgd region h ... | 1991 | 1664405 |
| insertion sites of the transposable element mariner are fixed in the genome of drosophila sechellia. | the abundance of the transposable element mariner differs dramatically in the genomes of the closely related species drosophila simulans, d. mauritiana, d. sechellia, and d. melanogaster. natural populations of d. simulans and d. mauritiana have 1-10 and 20-30 copies per diploid genome, respectively, and the insertion sites are polymorphic. the element has not been found in d. melanogaster. in this paper we show that d. sechellia, a species endemic to the seychelles islands, contains only two ma ... | 1991 | 1660073 |
| identification of nucleotide substitutions necessary for trans-activation of mariner transposable elements in drosophila: analysis of naturally occurring elements. | six copies of the mariner element from the genomes of drosophila mauritiana and drosophila simulans were chosen at random for dna sequencing and functional analysis and compared with the highly active element mos1 and the inactive element peach. all elements were 1286 base pairs in length, but among them there were 18 nucleotide differences. as assayed in drosophila melanogaster, three of the elements were apparently nonfunctional, two were marginally functional, and one had moderate activity th ... | 1991 | 1655567 |
| introduction of the transposable element mariner into the germline of drosophila melanogaster. | a chimeric white gene (wpch) and other constructs containing the transposable element mariner from drosophila mauritiana were introduced into the germline of drosophila melanogaster using transformation mediated by the p element. in the absence of other mariner elements, the wpch allele is genetically stable in both germ cells and somatic cells, indicating that the peach element (i.e., the particular copy of mariner inserted in the wpch allele) is inactive. however, in the presence of the active ... | 1991 | 1649067 |
| further observation of paternal transmission of drosophila mitochondrial dna by pcr selective amplification method. | by designing 3' ends of primers in pcr (polymerase chain reaction), a specific dna fragment was selectively amplified in the presence of a 10(3)-fold excess of highly homologous (sequence difference ca. 2%) opponent dna. this technique was applied in detecting paternal leakage of mitochondrial dna (mtdna) in intraspecific crosses of drosophila simulans and interspecific crosses of drosophila simulans and drosophila mauritiana. the mtdna types of their progeny were analysed by selective amplifica ... | 1992 | 1628820 |
| transmission of the hereditary s character in drosophila simulans: effects of aging and temperature treatments. | the expression of the s character of drosophila simulans associated to hereditary reovirus dsv is affected by the rearing temperature. the transmission of the s character and the consequences of the length of high temperature (28 degrees c) treatments on that transmission were investigated. larvae treated at 28 degrees c from eclosion to imaginal emergence produce few s individuals in the offspring. the offspring of larvae treated between the 144th hr of development (middle of the pupal stage) a ... | 1992 | 1607670 |
| interspecific comparison of the transformer gene of drosophila reveals an unusually high degree of evolutionary divergence. | the transformer (tra) gene of drosophila melanogaster occupies an intermediate position in the regulatory pathway controlling all aspects of somatic sexual differentiation. the female-specific expression of this gene's function is regulated by the sex lethal (sxl) gene, through a mechanism involving sex-specific alternative splicing of tra pre-mrna. the tra gene encodes a protein that is thought to act in conjunction with the transformer-2 (tra-2) gene product to control the sex-specific process ... | 1992 | 1592233 |
| a comprehensive study of genic variation in natural populations of drosophila melanogaster. vi. patterns and processes of genic divergence between d. melanogaster and its sibling species, drosophila simulans. | we present here an extensive set of data on allelic differences between homologous proteins of drosophila melanogaster and its sibling species, drosophila simulans, obtained by nondenaturing one-dimensional, and denaturing two-dimensional gel electrophoresis. the data suggest that, for these two species, (1) approximately 10% of protein-coding loci have no alleles in common in our sample, (2) the extent of genic variation at a locus (mean heterozygosity) within a species is not correlated with t ... | 1992 | 1582561 |
| intraspecific and interspecific variation at the y-ac-sc region of drosophila simulans and drosophila melanogaster. | a 2.2-kb region including the ac gene of drosophila simulans has been sequenced. interspecific divergence between drosophila melanogaster and d. simulans was estimated as 0.0695 and 0.0558 for silent and for all sites, respectively. estimated silent site divergence for the ac region is comparable to that estimated for other regions of the genome between these species, indicating that silent sites of the ac region are not under significantly stronger functional constraint. intraspecific variation ... | 1992 | 1582559 |
| location of x-linked polygenic effects causing sterility in male hybrids of drosophila simulans and d. mauritiana. | there is general agreement that hybrid male sterility in drosophila is caused by changes at several (perhaps many) factors, most of them located on the x chromosome. these factors have been generally considered as major genes, each one of them able to bring about sterility by itself. however, the evidence on this last point is not conclusive. in principle, the possibility that they correspond to located polygenic effects instead of genes with a large effect cannot be excluded. this paper shows t ... | 1992 | 1559838 |
| an empirical test of the meiotic drive models of hybrid sterility: sex-ratio data from hybrids between drosophila simulans and drosophila sechellia. | recently, there has been much discussion regarding the hypothesis that divergence of meiotic drive systems in isolated populations can generate the patterns of reproductive isolation observed in animal hybridizations. one prediction from this hypothesis is that the sex ratio of hybrids with heterospecific sex chromosomes should greatly deviate from the mendelian expectation of 50% female. from sex-ratio data in our drosophila hybridization studies, we find no such deviation: the sex ratio of off ... | 1992 | 1551573 |
| sequence analysis of the indirect flight muscle actin-encoding gene of drosophila simulans. | a genomic clone of the drosophila simulans indirect flight muscle actin-encoding gene (act88f) has been isolated, and the sequence of a 3358-nucleotide segment corresponding to the drosophila melanogaster act88f transcription unit is presented. the act88f homologs in these two sibling species encode identical proteins and the general genomic organization of the act88f locus is highly conserved, including the location of the transcription start point, and the size and position of intron/exon junc ... | 1992 | 1511890 |
| dynamics of cytoplasmic incompatibility and mtdna variation in natural drosophila simulans populations. | in drosophila simulans a cytoplasmically transmitted microorganism causes reduced egg hatch when infected males mate with uninfected females. the infection is rapidly spreading northward in california. data on a specific mtdna restriction site length polymorphism show that changes in the frequency of mtdna variants are associated with this spread. all infected flies possess the same mtdna allele, whereas the uninfected flies are polymorphic. given that both paternal inheritance of the infection ... | 1992 | 1468627 |
| population genetics of polymorphism and divergence. | frequencies of mutant sites are modeled as a poisson random field in two species that share a sufficiently recent common ancestor. the selective effect of the new alleles can be favorable, neutral, or detrimental. the model is applied to the sample configurations of nucleotides in the alcohol dehydrogenase gene (adh) in drosophila simulans and drosophila yakuba. assuming a synonymous mutation rate of 1.5 x 10(-8) per site per year and 10 generations per year, we obtain estimates for the effectiv ... | 1992 | 1459433 |
| genetics of sexual isolation in females of the drosophila simulans species complex. | genetic analysis of hybrids between drosophila simulans and d. sechellia shows that sexual isolation in females is caused by at least two genes, one on each major autosome, while the x chromosome has no effect. these results are similar to those of a previous study of hybrids between d. simulans and another sibling species, d. mauritiana. in this latter hybridization, each arm of the second chromosome carries genes causing sexual isolation in females, implying a total divergence of at least thre ... | 1992 | 1452013 |
| xenobiotic-metabolizing enzymes and benzo[a]pyrene metabolism in the benzo[a]pyrene-sensitive mutant strain of drosophila simulans. | basal levels of aryl hydrocarbon hydroxylase, epoxide hydrolase and glutathione s-transferase enzyme activities, cytochrome p-450 content and inducibility of enzymes with phenobarbital were found to be similar in the microsomes of d. simulans mutant strain 364yv, which is sensitive to the toxic and mutagenic effects of benzo[a]pyrene (bp), and of the wild resistant turku strain. in contrast, increases in the rate of bp turnover per molecule of cytochrome p-450, intensity of the hemoprotein band ... | 1992 | 1383701 |
| efficient amplification of drosophila simulans copia directed by high-level reverse transcriptase activity associated with copia virus-like particles. | the number of retrotransposon copia per genome in drosophila melanogaster cultured cells is two to three times higher than that in d. melanogaster embryo cells. here, we have found that the genome of the related species, drosophila simulans, contains in cultured cells more efficiently amplified copia dna (approximately ten fold). furthermore, we analyzed copia virus-like particles (vlps) prepared from d. melanogaster and d. simulans cultured cells, which contain copia rna and reverse transcripta ... | 1992 | 1383092 |
| a drosophila simulans mutant strain sensitive to benzo[a]pyrene and 2-acetylaminofluorene. | we have identified a drosophila simulans mutant, 364 yu, that is sensitive to the toxic effects of the procarcinogens b(a)p and 2-aaf. heterozygotes obtained by crossing it to the wild resistant turku strain (female 364 yu x male turku) were more sensitive than heterozygotes obtained from the reciprocal cross (female turku x male 364 yu) to both the toxic and the mutagenic effects of b(a)p in drosophila tests that measured lethality and the induction of somatic mosaicism, respectively. the non-c ... | 1992 | 1378181 |
| polymorphism and divergence in the mst26a male accessory gland gene region in drosophila. | drosophila males, like males of most other insects, transfer a group of specific proteins to the females during mating. these proteins are produced primarily in the accessory gland and are likely to influence the female's reproduction. the results of studies of dna sequence polymorphism and divergence in two genes coding for male accessory gland proteins of drosophila are reported here. the mst26aa and mst26ab transcription units are tandemly arranged in a approximately 1.6-kb segment in drosoph ... | 1992 | 1361475 |
| molecular identification of wolbachia, the agent of cytoplasmic incompatibility in drosophila simulans, and variability in relation with host mitochondrial types. | sequences of a segment of the 16s ribosomal dna of wolbachia, a rickettsia-like microorganism responsible for cytoplasmic incompatibility in drosophila simulans, have been obtained after polymerase chain reaction (pcr) amplification. their comparison with other eubacterial sequences allows us to assign these endosymbionts to the alpha subdivision of purple bacteria. four related sequences have been obtained for microorganisms carried by eight isofemale lines representative of the three mitochond ... | 1992 | 1350096 |
| localization of ribosomal dna insertion elements in polytene chromosomes of drosophila simulans, drosophila mauritiana and their interspecific hybrids. | the locations of the ribosomal dna (rdna) insertion elements type i and type ii along the polytene chromosomes of three drosophila species of the melanogaster subgroup--d. simulans, d. mauritiana and d. melanogaster--have been compared. in situ hybridization has shown that the intragenomic distribution of type i as well as of type ii insertions is different for these related species. in particular, we have revealed rdna-free autosomal sites, containing type ii element sequences within the d. sim ... | 1992 | 1325940 |
| [comparative analysis of the localization and mobility of retrotransposons in sibling species drosophila simulans and drosophila melanogaster]. | the distribution of four retrotransposon families (mdg1, mdg3, mdg4 and copia) on polytene chromosomes of different (from 9 to 15) drosophila simulans strains is studied. the mean number of mdg1 and copia euchromatic hybridization sites (3 sites for each element) is drastically decreased in d. simulans in comparison with d. melanogaster (24 and 18 sites respectively). the mean number of mdg3 sites of hybridization is 5 in d. simulans against 12 in d. melanogaster. as for mdg4 both species have o ... | 1992 | 1322343 |
| sequence analysis of active mariner elements in natural populations of drosophila simulans. | active and inactive mariner elements from natural and laboratory populations of drosophila simulans were isolated and sequenced in order to assess their nucleotide variability and to compare them with previously isolated mariner elements from the sibling species drosophila mauritiana and drosophila sechellia. the active elements of d. simulans are very similar among themselves (average 99.7% nucleotide identity), suggesting that the level of mariner expression in different natural populations is ... | 1992 | 1312979 |
| spontaneous recombination in males of drosophila simulans. | spontaneous recombination in males of drosophila simulans is reported for the first time. both second-chromosome and third-chromosome male recombination was observed in lines that had been captured from natural populations. | 1976 | 1068114 |
| the pattern of polytene chromosome synapsis in drosophila species and interspecific hybrids. | the pairing of polytene chromosomes was investigated in drosophila melanogaster, drosophila simulans and their hybrids as well as in species of the d. virilis group and in f1 hybrids between the species of this group. the study of frequency and extent of asynapsis revealed non-random distribution along chromosome arms both in interspecific hybrids and pure drosophila species. it is suggested that definite chromosome regions exhibiting high pairing frequency serve as initiation sites of synapsis ... | 1976 | 1001143 |
| genetic analysis of phototactic behavior in drosophila simulans. | phototaxis mazes have been employed to select photopositive and photonegative strains of drosophila simulans. the results suggest that phototactic behavior in d. simulans, as in other drosophila species, is a polygenic trait. hybridization using divergent strains revealed that the genes controlling negative phototactic behavior in d. simulans are autosomal, as opposed to d. melanogaster in which negative phototactic behavior is known to be very strongly sex-linked. | 1977 | 863226 |
| genetic analysis of aspartate aminotransferase isozymes from hybrids between drosophila melanogaster and drosophila simulans and mutagen-induced isozyme variants. | the aspartate aminotransferases (designated got1 and got2) are two enzymes of drosophila melanogaster for which naturally occurring electrophoretic variants were not found. there is an electrophoretic difference between d. melanogaster and d. simulans. since the f1 hybrid offspring of these species are sterile, a genetic analysis of the ordinary type cannot be done on differences between the two species. a method was devised to make "partial hybrids" in which one chromosome arm is homozygous for ... | 1976 | 823072 |
| [comparative study of salivary gland polytene chromosome asynapsis in larvae of drosophila melanogaster, drosophila simulans and their hybrids]. | quantitative comparative study of larvae salivary gland chromosome asynapsis has been performed on 3l arm for sibling species of drosophila melanogaster, d. simulans and their hybrids (d. melanogaster female x d. simulans hermaphrodite). a frequency of asynapsis occurence, an asynapsis localization and distributions of asynapsis terminal points and asynapsis lengths were determined. it is revealed that parent species are very similar as regards to quantitative characteristics studied. for hybrid ... | 1975 | 814050 |
| courtship song and mating speed in hybrids between drosophila melanogaster and drosophila simulans. | courtship song and mating speed of hybrids between drosophila melanogaster and d. simulans were investigated. the courtship song of hybrid males is identical to that of d. simulans, suggesting that x chromosome determination, known from the cross between d. pseudoobscura and d. persimilis, is also possible here. wingbeat frequency of hybrids is intermediate between that of the two parents, demonstrating that courtship song and wingbeat frequency are inherited independently of each other. in mati ... | 1975 | 811205 |
| phototactic responses along a gradient of light intensities for the sibling species drosophila melanogaster and drosophila simulans. | the phototactic responses of four recently collected isofemale strains of drosophila melanogaster and drosophila simulans were measured in a light gradient from 590 to 10 lux. high light intensities were preferred by most flies, but a small proportion of flies preferred the lowest light intensity. based on the strains tested, d. simulans showed greater phototaxis than d. melanogaster, and within each species variability was found. the niche breadth of d. melanogaster appears likely to be greater ... | 1975 | 803833 |
| genotype-temperature interaction for longevity in natural populations of drosophila simulans. | 1977 | 604086 | |
| behavioral role of the sexcombs in drosophila melanogaster and drosophila simulans. | the sexcombs were amputated from males of three strains of drosophila melanogaster and one strain of d. simulans in order to assess the importance of these structures in the sexual behavior of these species. in d. melanogaster the sexcombs are important in attempts to copulate with the female. their removal delays copulation but does not suppress it entirely. other aspects of courtship are not influenced by removal of the sexcombs. strain differences in quanitative aspects of courtship were foun ... | 1977 | 411471 |
| [role of propionic acid, yeasts and ethyl alcohol in regulating the activity of h-factor in drosophila simulans]. | effects of yeast, propionic acid and ethanol on the activity of h-factor, which sharply increases the frequency of somatic recombination in x-chromosomes of dorsal prothoracal disc cells in drosophila simulans are studied. the frequency of yellow and singed mosaic spots in heterozygous yw ++/++sn1vhd. melanogaster females, inherited h-factor from the father (the stock sn1v) is estimated. the results of the varience analysis have shown that yeast and propionic acid regulate the activity of h-fact ... | 1977 | 355052 |
| electrophoretic variability in island populations of drosophila simulans and drosophila immigrans. | genetic structure and variability were investigated in several hawaiian populations of d. simulans and d. immigrans. genetic variability is lower in hawaiian populations of d. simulans than in texas populations, and allelic differences exist as well. for d. immigrans, hawaiian and korean populations are similar in variability, allelic content, and gene frequencies. several hypothesis are advanced to account for the patterns in gene variation observed between island and continental populations of ... | 1976 | 184779 |
| relationships within the melanogaster species subgroup of the genus drosophila (sophophora) i. inversion polymorphisms in drosophila melanogaster and drosophila simulans. | 1976 | 5729 |