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the linkage system of eight sex-linked characters of drosophila virilis (data of metz). 191916576347
the arrangement of genes in drosophila virilis. 192016576483
observations on the sterility of mutant hybrids in drosophila virilis. 192016576511
homologous genes and linear linkage in drosophila virilis. 192016576549
reddish-a frequently "mutating" character in drosophila virilis. 192616576949
magenta-alpha-a third frequently mutating character in drosophila virilis. 192716577062
genetic factors stimulating mutability of the miniature-gamma wing character of drosophila virilis. 192916577248
non-disjunction of the x-chromosome in drosophila virilis. 193016577296
relation between the x-ray dosage and the frequency of primary non-disjunctions of x-chromosomes in drosophila virilis. 193016577297
rate of instability of miniature-3 gamma gene of drosophila virilis in the males in the homozygous and in the heterozygous females. 193216577490
a mutant of drosophila melanogaster resembling the so-called unstable genes of drosophila virilis. 194316578075
miniature-alpha-a second frequently mutating character in drosophila virilis. 192616587134
changes in the rate of mutability of the mutable miniature gene of drosophila virilis. 192916587522
interaction of ruffled and rounded genes of drosophila virilis. 193216587691
effect of temperature on the rate of change of the unstable miniature-3 gamma gene of drosophila virilis. 193216587710
effect of x-rays on the rate of change in the unstable miniature-3 gene of the drosophila virilis. 193416587835
genetics of hermaphroditism in drosophila virilis. 193416587916
intersexuality in drosophila virilis and its bearing on sex determination. 193816588214
chromosome homologies in two sub-species of drosophila virilis. 194016588407
radiation damage in the developing germ cells of drosophila virilis. 195516589795
biological damage in developing germ cells of drosophila virilis in oxygen and nitrogen with 14-mev neutrons. 195816590336
molecular phylogeny of the drosophila virilis section (diptera: drosophilidae) based on mitochondrial and nuclear sequences.regardless of the well-documented virilis species group, most groups of the drosophila virilis section have not been completely studied at molecular level since it was suggested. therefore, phylogenetic relationships among and within species groups of the virilis section are generally unknown. in present paper, the complete mitochondrial nd2 gene and fragment of coi gene in combination with a nuclear gene, adh coding region, were used to derive the most extensive molecular phylogeny to date for ...200616678448
dopamine affects the level of 20-hydroxyecdysone in drosophila virilis females. 201616739488
the evolutionary history of the transposable element penelope in the drosophila virilis group of species.we have used phylogenetic techniques to study the evolutionary history of the penelope transposable element in the drosophila virilis species group. two divergent types of penelope have been detected, one previously described, clade i, and a new one which we have termed clade iii. the phylogeny of some copies of the penelope clade i element was partially consistent with the species phylogeny of the d. montana subphylad, suggesting cospeciation and allowing the estimation of the evolutionary rate ...200616830099
comparative polytene chromosome maps of d. montana and d. virilis.chromosomal inversion polymorphism was characterized in finnish drosophila montana populations. a total of 14 polymorphic inversions were observed in finnish d. montana of which nine had not been described before. the number of polymorphic inversions in each chromosome was not significantly different from that expected, assuming equal chance of occurrence in the euchromatic genome. there was, however, no correlation between the number of polymorphic inversions and that of fixed inversions in eac ...200716906413
mechanisms of programmed cell death during oogenesis in drosophila virilis.we describe the features of programmed cell death occurring in the egg chambers of drosophila virilis during mid-oogenesis and late oogenesis. during mid-oogenesis, the spontaneously degenerating egg chambers exhibit typical characteristics of apoptotic cell death. as revealed by propidium iodide, rhodamine-conjugated phalloidin staining, and the tunel assay, respectively, the nurse cells contain condensed chromatin, altered actin cytoskeleton, and fragmented dna. in vitro caspase activity assay ...200717004067
apoptosis and autophagy function cooperatively for the efficacious execution of programmed nurse cell death during drosophila virilis oogenesis.programmed cell death consists of two major types, apoptotic and autophagic, both of which are mainly defined by morphological criteria. our findings indicate that both types of programmed cell death occur in the ovarian nurse cells during middle- and late-oogenesis of drosophila virilis. during mid-oogenesis, the spontaneously degenerated egg chambers exhibit typical characteristics of apoptotic cell death. their nurse cells contain condensed chromatin and fragmented dna, whereas active caspase ...200717183224
the linkage of eight sex-linked characters in drosophila virilis. 191817245900
effects of temperature on length of vestigial wing in drosophila virilis. 192617246471
mutable characters of drosophila virilis i. reddish-alpha body character. 192817246554
mutants and crossing over in the dot-like chromosome of drosophila virilis. 193317246680
further studies on factor interaction in drosophila virilis. 193517246755
a study of intersexuality in drosophila virilis. 193917246938
an analysis of the chromosomes of the two sub-species drosophila virilis virilis and drosophila virilis americana. 193917246953
sexual isolation studies in the species complex drosophila virilis. 194217247038
the production of chromosome interchanges in drosophila virilis. 194917247309
v-type position effects of a gene in drosophila virilis normally located in heterochromatin. 195317247441
chromosome segregation in drosophila virilis males with multiple sex chromosomes. 195617247672
radiation damage in the developing germ cells of drosophila virilis from fast neutron treatment. 195817247770
biological damage in mature and immature germ cells of drosophila virilis with ionizing radiations. 195917247901
synergistic effect of inbreeding on viability in drosophila virilis.the effect of inbreeding on egg to adult viability was determined for drosophila virilis over a wide range of inbreeding levels (0 < f <.734). the quantity -log(e) (viability) was found to be a curvilinear function of f, indicating synergistic interaction among loci. the curvature was not evident, however, below f =.500. the values of a and b (mortonet al. 1956) were calculated to be.06 and.77-.86, respectively. this extremely small value of a yielded a very large value for the b/a ratio i.e., 1 ...197217248583
the cytogenetic study of crossing over in interspecific hybrids between drosophila virilis and d. texana.spontaneous crossing over was studied by means of combined cytological and genetic methods in f(1)drosophila virilis x d. texana females (series i) and in d. virilis females carrying a d. texana fifth chromosome in heterozygous condition (series ii). the main criterion utilized to distinguish the oogonial crossovers from the meiotic ones is the identity of cytological positions of genetic exchange in crossovers constituting a cluster. five clusters of crossovers with identical positions of excha ...197617248719
phylogeographic patterns in drosophila montana.the drosophila virilis species group offers valuable opportunities for studying the roles of chromosomal re-arrangements and mating signals in speciation. the 13 species are divided into two subgroups, the montana and virilis 'phylads'. there is greater differentiation among species within the montana phylad in both karyotype and acoustic signals than exists among members of the virilis phylad. drosophila montana is a divergent species which is included in the montana phylad. here, we analyse th ...200717305862
[a rapd fingerprinting of sibling species of the drosophila virilis group].a comparative analysis of the sibling species of drosophila virilis was performed by rapd-pcr technique using a set of random primers. the degree of relatedness was studied by cluster analysis (upgma) and multi-dimensional scaling. the resulting pattern of species relationships contradicts the classical taxonomy. the main result of the cluster analysis is that d. virilis does not cluster with the remaining three species of its phylad, while according to multidimensional scaling, d. virilis is eq ...200717333946
effects of juvenile hormone and 20-hydroxyecdysone on alkaline phosphatase activity in drosophila under normal and heat stress conditions.the effect of 20-hydroxyecdysone (20e) and the juvenile hormone (jh) on the activity of the alkaline phosphatase (alp) has been studied in young females of wild-type drosophila virilis and drosophila melanogaster under normal conditions and under heat stress (38 degrees c). both 20e feeding of the flies and jh application led to a substantial rise in alp activity. alp activity was also measured in young females of a jh-deficient strain of d. melanogaster, apterous(56f). a decrease in the enzyme ...200717433361
intracellular targeting of telomeric retrotransposon gag proteins of distantly related drosophila species.the retrotransposons that maintain telomeres in drosophila melanogaster have unique features that are shared across all drosophila species but are not found in other retrotransposons. comparative analysis of these features provides insight into their importance for telomere maintenance in drosophila. gag proteins encoded by het-a(mel) and tart(mel) are efficiently and cooperatively targeted to telomeres in interphase nuclei, a behavior that may facilitate telomere-specific transposition. drosoph ...200717483480
dopamine and octopamine regulate 20-hydroxyecdysone level in vivo in drosophila.the effects of increased level of dopamine (da) (feeding flies with da precursor, l-dihydroxyphenylalanine, l-dopa) on the level of 20-hydroxyecdysone (20e) and on juvenile hormone (jh) metabolism in young (2-day-old) wild type females (the strain wt) of drosophila virilis have been studied. feeding the flies with l-dopa increased da content by a factor of 2.5, and led to a considerable increase in 20e level and a decrease of jh degradation (an increase in jh level). we have also measured the le ...200717523172
genetic analysis of cuticular hydrocarbons and their effect on courtship in drosophila virilis and d. lummei.genetical factors controlling the cuticular hydrocarbons (chc) of drosophila virilis and d. lummei, and the effect of chc on female attractivity were studied. a strong sexual dimorphism was found in d. virilis where (z)-10-heneicosene and (z)-11-pentacosene were major chc for males and females, respectively. in d. lummei, (z)-9-pentacosene was the major chc for both sexes. these chc are under a complex genetical control: the level of male (z)-10-heneicosene was mainly sex-linked; chromosome 2 ex ...200717557202
juvenile hormonal activity of mono- and polyenehomobenzenes in drosophila virilis, spodoptera frugiperda and araschnia levana.a series of mono- and polyenehomobenzenes was synthesised by a highly regioselective palladium-catalysed allylic alkylation of substituted and unsubstituted benzylic grignard reagents employing catalytic amounts of catalyst and tested for juvenile hormone activity on the fruit fly drosophila virilis sturtevant (diptera: drosophilidae), on an important agricultural pest species, the fall armyworm spodoptera frugiperda je smith (lepidoptera: noctuidae), and on the map butterfly araschnia levana l. ...200717573681
the extent of variation in male song, wing and genital characters among allopatric drosophila montana populations.drosophila montana, a species of the drosophila virilis group, has distributed around the northern hemisphere. phylogeographic analyses of two north american and one eurasian population of this species offer a good background for the studies on the extent of variation in phenotypic traits between populations as well as for tracing the selection pressures likely to play a role in character divergence. in the present paper, we studied variation in the male courtship song, wing and genital characte ...200717584251
gonadotropins influence alkaline phosphatase activity in drosophila virilis. 200717695320
role of ecdysone 20-monooxygenase in regulation of 20-hydroxyecdysone levels by juvenile hormone and biogenic amines in drosophila.the effects of increased levels of dopamine (feeding flies with dopamine precursor, l: -dihydroxyphenylalanine) and octopamine (feeding flies with octopamine) on ecdysone 20-monooxygenase activity in young (2 days old) wild type females (the strain wt) of drosophila virilis have been studied. l: -dihydroxyphenylalanine and octopamine feeding increases ecdysone 20-monooxygenase activity by a factor of 1.6 and 1.7, respectively. ecdysone 20-monooxygenase activity in the young (1 day old) octopamin ...200817703313
correspondence between chromosome number and linkage groups in drosophila virilis. 192017753070
effect of implanted adult corpora allata on that of host in two species of drosophila.experiments to show the effect of implanted adult corpora allata on that of the host have given negative results in drosophila melanogaster, while the presumed compensatory effect has been verified in drosophila virilis. reasons are presented which suggest that the nature of the latter effect should be further analyzed.196117817396
[ecdysone 20-monooxygenase activity in drosophila virilis strains varying in ecdysteroid response to heat stress].the effect of various duration of heat stress (38 degrees c) on the activity of ecdysone 20-monooxygenase converting ecdysone into 20-hydroxyecdysone has been studied in d. virilis of wild type and mutant strain females, which differ by the mode of heat stress response of ecdysone and 20-hydroxyecdysone. we are the first to show that heat stress induces activity of ecdysone 20-monooxygenase in drosophila females and enzyme activity correlates with the level of 20-hydroxyecdysone.200717899820
variation in male courtship song traits in drosophila virilis: the effects of selection and drift on song divergence at the intraspecific level.genetic and phenotypic divergence of drosophila virilis laboratory strains originating from different parts of the species range were studied with the aid of microsatellite markers and by analysing male courtship songs. the strains from america, europe, continental asia and japan showed moderate geographic clustering both at the genetic level and in several traits of the male song. the genetic distances and the song divergence of the strains did not show significant association, which suggests t ...200817990093
microsatellite-based species identification method for drosophila virilis group species.species of the d. virilis group are widely used in evolutionary research, but the individuals of different species are difficult to distinguish from each other morphologically. we constructed a fast and easy microsatellite-based identification method for the species of the group occurring sympatrically in northern europe. the neighbor joining tree based on 14 microsatellite loci also gave a good resolution of the species divergence pattern in the whole group.200718031356
juvenile hormone and 20-hydroxyecdysone regulate n-acetyltransferase activity in drosophila virilis. 200718064820
the induction of aristapedia by nitrogen mustard in drosophila virilis. 194918151963
the production of chromosome interchanges in drosophila virilis. 194818207805
signals of demographic expansion in drosophila virilis.the pattern of genetic variation within and among populations of a species is strongly affected by its phylogeographic history. analyses based on putatively neutral markers provide data from which past events, such as population expansions and colonizations, can be inferred. drosophila virilis is a cosmopolitan species belonging to the virilis group, where divergence times between different phylads go back to the early miocene. we analysed mitochondrial dna sequence variation among 35 drosophila ...200818298823
stanislaw smreczynskis legacy and the department of zoology of the jagiellonian university of krakow (poland).this article covers the origin and development of scientific interest in insect and amphibian developmental biology at the department of systematic zoology and zoogeography of the jagiellonian university. the greater part of this historical account is devoted to professor stanislaw smreczynski (1899-1975), the founding father of the department, and comments on his biography and research achievements in the field of animal experimental embryology. a particular emphasis is on smreczynski's contrib ...200818311698
molecular dissection of penelope transposable element regulatory machinery.penelope-like elements (ples) represent a new class of retroelements identified in more than 80 species belonging to at least 10 animal phyla. penelope isolated from drosophila virilis is the only known transpositionally active representative of this class. although the size and structure of the penelope major transcript has been previously described in both d. virilis and d. melanogaster transgenic strains, the architecture of the penelope regulatory region remains unknown. in order to determin ...200818319284
expression pattern diversity and functional conservation between retroposed prat genes from drosophila melanogaster and drosophila virilis.gene duplication by retrotransposition duplicates only the coding and untranslated regions of a gene and, thus, biases retroduplicated genes toward having different expression patterns from their parental genes. as such, genes duplicated by retrotransposition are more likely to develop novel expression domains. to explore this idea further, we used the prat/prat2 gene duplication in drosophila as a case study to examine the aftermath of a retrotransposition event that resulted in both the parent ...200818392760
[the relationships among the species of the drosophila virilis group inferred from the gene ras1 sequences].comparative analysis of a group of closely related drosophila species (d. virilis, d. lummei, d. novamexicana, d. americana texana, d. flavomontana, d. montana, d. borealis, d. lacicola, d. littoralis, d. kanekoi, and d. ezoana) was conducted based on an incomplete sequence of gene ras1. the pattern of the relationships among the species corresponded to that expected from analysis of morphological and cytogenetic characters. statistical data favoring neutrality of the substitutions examined in t ...200818664137
an old bilbo-like non-ltr retroelement insertion provides insight into the relationship of species of the virilis group.in drosophila, at the population and species level, fixation of a te insertion is an unlikely fate. of the few reported fixations at the species level most involve non-ltr retroelements. in this work we report the fixation of a non-ltr retroelement in five species (drosophila littoralis, drosophila virilis, drosophila lummei, drosophila americana and drosophila novamexicana) of the virilis group of drosophila. in most species, this te insertion is being lost through the accumulation of small del ...200818775768
gene structure of drosophila diaphorase-1: diversity of transcripts in adult males and females, in different organs and at different stages of development.the gene eg:22e5.5 or cg4199 (accession number o77266, q9w529) from berkeley drosophila genome project (bdgp) was found using the partial amino acid sequences of three tryptic peptides obtained from purified drosophila virilis diaphorase-1. this gene is located on the x chromosome at position 2c9-2c10. the structure of the gene reveals three exons and two long introns. using bdgp, we found six transcripts in this gene. the difference between these transcripts is in their 5' ends; the 3' ends of ...200818776642
gonadotropins affect tyrosine decarboxylase activity in drosophila virilis. 201318853763
caudal, a key developmental regulator, is a dpe-specific transcriptional factor.the regulation of gene transcription is critical for the proper development and growth of an organism. the transcription of protein-coding genes initiates at the rna polymerase ii core promoter, which is a diverse module that can be controlled by many different elements such as the tata box and downstream core promoter element (dpe). to understand the basis for core promoter diversity, we explored potential biological functions of the dpe. we found that nearly all of the drosophila homeotic (hox ...200818923080
an x chromosome effect responsible for asymmetric reproductive isolation between male drosophila virilis and heterospecific females.reproductive isolation between closely related species is expressed through uncoordinated courtship, failed fertilization, and (or) postzygotic barriers. behavioural components of mating often form an initial barrier to hybridization between species. in many animals, females are responsible for mating discrimination in both intra- and interspecific crosses; males of drosophila virilis group represent an exception to this trend. using overall productivity tests, we show that a lower proportion of ...200919132071
gonadotropins regulate tyrosine hydroxylase activity in drosophila virilis. 201319230379
[comparative analysis of hsp70 gene cluster in drosophila virilis species group].we cloned and sequenced one of drosophila montana hsp70 genes. 3'-flanking region of this particular copy contains fragment of sgm mobile element. previously this element was found within hsp70 3'-flanking region of other species of the virilis species group namely d. virilis and d. lummei. we have described reorganization of hsp70 gene cluster in one of d. virilis strains involving full-length sgm. our data enable one to suggest evolutionary conservatism of sgm localization within hsp70 gene cl ...200919334525
analysis of two promoters that control the expression of the gtp cyclohydrolase i gene in drosophila melanogaster.gtp cyclohydrolase i (gtpch) is a key enzyme in the de novo synthesis of tetrahydrobiopterin. previously, the drosophila melanogaster gtpch gene has been shown to be expressed from two different promoters (p1 and p2). in our study, the 5'-flanking dna regions required for p1 and p2 promoter activities were characterized using transient expression assay. the dna regions between -98 and +31, and between -73 and +35 are required for efficient p1 and p2 promoter activities, respectively. the regions ...200919387565
[structural and functional analysis of the representatives of a new class of retroelements in drosophila species].various copies of mobile element penelope previously described in drosophila virilis have been investigated in different strains of d. virilis and transgenic strains of d. melanogaster transformed by p-based constructs containing full-size copy of penelope. it has been demonstrated that most of penelope copies in both species carry large terminal inverted repeats (tir) and contain deletions of various size at their 5'end of orf. junctions between tir and orf usually carry microhomology of variou ...200919425503
isolation, characterization and anti-cancer activity of sk84, a novel glycine-rich antimicrobial peptide from drosophila virilis.we report herein the isolation and characterization of a novel glycine-rich antimicrobial peptide purified from the larvae of drosophila virilis. a range of chromatographic methods was used for isolation and its antibacterial activity against bacillus subtilis was employed to screen for the most active fractions. the peptide, termed sk84 due to its n-terminal serine, c-terminal lysine and a total of 84 residues, was completed sequenced using rt-pcr cdna cloning. sk84 contains a high level of gly ...201019799950
the genetics of postmating, prezygotic reproductive isolation between drosophila virilis and d. americana.many studies have demonstrated the rapid diversification of reproductive genes that function after mating but before fertilization. this process might lead to the evolution of postmating, prezygotic barriers between species. here, i investigate the phenotypic and genetic basis of postmating, prezygotic isolation between two closely related species of drosophila, drosophila virilis and d. americana. i show that a strong barrier to interspecific fertilization results in a 99% reduction in progeny ...201019917764
a microsatellite linkage map for drosophila montana shows large variation in recombination rates, and a courtship song trait maps to an area of low recombination.current advances in genetic analysis are opening up our knowledge of the genetics of species differences, but challenges remain, particularly for out-bred natural populations. we constructed a microsatellite-based linkage map for two out-bred lines of drosophila montana derived from divergent populations by taking advantage of the drosophila virilis genome and available cytological maps of both species. although the placement of markers was quite consistent with cytological predictions, the map ...201020040000
simple y-autosomal incompatibilities cause hybrid male sterility in reciprocal crosses between drosophila virilis and d. americana.postzygotic reproductive isolation evolves when hybrid incompatibilities accumulate between diverging populations. here, i examine the genetic basis of hybrid male sterility between two species of drosophila, drosophila virilis and d. americana. from these analyses, i reach several conclusions. first, neither species carries any autosomal dominant hybrid male sterility alleles: reciprocal f(1) hybrid males are perfectly fertile. second, later generation (backcross and f(2)) hybrid male sterility ...201020048051
the brain can eat: establishing the existence of a central pattern generator for feeding in third instar larvae of drosophila virilis and drosophila melanogaster.to establish the existence of a central pattern generator for feeding in the larval central nervous system of two drosophila species, the gross anatomy of feeding related muscles and their innervation is described, the motor units of the muscles identified and rhythmic motor output recorded from the isolated cns. the cibarial dilator muscles that mediate food ingestion are innervated by the frontal nerve. their motor pathway projects from the brain through the antennal nerves, the frontal connec ...201020074578
dopamine down-regulates activity of alkaline phosphatase in drosophila: the role of d2-like receptors.the effect of a rise in dopamine (da) level as a result of a mutation, stress or pharmacological treatment on the activity of the enzyme of its synthesis, alkaline phosphatase (alp) in females of drosophila virilis and drosophila melanogaster has been studied. it has been found that regardless of its nature, a rise in da level has a negative effect on alp activity, which indicates that da down-regulates activity of the enzyme. the effects of bromocriptine (an agonist of drosophila dopamine 2-lik ...201020303975
evolution of a distinct genomic domain in drosophila: comparative analysis of the dot chromosome in drosophila melanogaster and drosophila virilis.the distal arm of the fourth ("dot") chromosome of drosophila melanogaster is unusual in that it exhibits an amalgamation of heterochromatic properties (e.g., dense packaging, late replication) and euchromatic properties (e.g., gene density similar to euchromatic domains, replication during polytenization). to examine the evolution of this unusual domain, we undertook a comparative study by generating high-quality sequence data and manually curating gene models for the dot chromosome of d. viril ...201020479145
small rna-based silencing strategies for transposons in the process of invading drosophila species.colonization of a host by an active transposon can increase mutation rates or cause sterility, a phenotype termed hybrid dysgenesis. as an example, intercrosses of certain drosophila virilis strains can produce dysgenic progeny. the penelope element is present only in a subset of laboratory strains and has been implicated as a causative agent of the dysgenic phenotype. we have also introduced penelope into drosophila melanogaster, which are otherwise naive to the element. we have taken advantage ...201020581131
[notch122, mutation of notch locus abruptex type in drosophila virilis: characteristics of genetic interactions].a drosophila virilis notch122 mutant has been isolated and genetically identified which is similar to notch drosophila melanogaster abruptex type alleles. some possible peculiarities of genetic interactions of notch alleles of abruptex type are discussed.201520608160
evolution of diverse mechanisms for protecting chromosome ends by drosophila tart telomere retrotransposons.the retrotransposons het-a, tart, and tahre, which maintain drosophila telomeres, transpose specifically onto chromosome ends to form long arrays that extend the chromosome and compensate for terminal loss. because they transpose by target-primed reverse transcription, each element is oriented so that its 5' end serves as the extreme end of the chromosome until another element transposes to occupy the terminal position. thus 5' sequences are at risk for terminal erosion while the element is at t ...201021088221
polycomb-dependent regulatory contacts between distant hox loci in drosophila.in drosophila melanogaster, hox genes are organized in an anterior and a posterior cluster, called antennapedia complex and bithorax complex, located on the same chromosome arm and separated by 10 mb of dna. both clusters are repressed by polycomb group (pcg) proteins. here, we show that genes of the two hox complexes can interact within nuclear pcg bodies in tissues where they are corepressed. this colocalization increases during development and depends on pcg proteins. hox gene contacts are co ...201121241892
[morphologic and molecular manifestations of hybrid dysgenesis in ontogenesis of drosophila virilis].disorders of germ track cell development that take place in crossbreeding of certain lines of drosophila virilis and lead to hybrid dysgenesis (hd) syndrome have been studied. polar cells and germ line cells were identified with specific antibodies against vasa protein. it has been shown that abnormalities of formation of primary gonads takes place already at the 11-12 stage of embryo development and the consequences of germ line cell death lead to disorders of gonad development at the following ...201121268367
evidence for evolutionary constraints in drosophila metal biology.mutations in single drosophila melanogaster genes can alter total body metal accumulation. we therefore asked whether evolutionary constraints maintain biologically abundant metal ions (iron, copper, manganese and zinc) to similar concentrations in different species of drosophilidae, or whether metal homeostasis is a highly adaptable trait as shown previously for triglyceride and glycogen storage. to avoid dietary influences, only species able to grow and reproduce on a standard laboratory mediu ...201121293906
resolving the phylogenetic relationships and evolutionary history of the drosophila virilis group using multilocus data.the drosophila virilis group is one of the major lineages of drosophila previously recognised and it has been used as a model for different types of studies. it comprises 13 species whose phylogenetic relationships are not well resolved. in the present study, six nuclear genes (adh, fused, gpdh, nona, cg9631 and cg7219) and the mitochondrial ribosomal rna genes (12s-16s) have been used to estimate the evolutionary tree of the group using different methods of phylogenetic reconstruction. differen ...201121571080
elav-mediated 3'-end processing of ewg transcripts is evolutionarily conserved despite sequence degeneration of the elav-binding site.regulation of alternative mrna processing by elav (embryonic lethal abnormal visual system)/hu proteins is mediated by binding to au-rich elements of low complexity. since such sequences diverge very rapidly during evolution, it has not been clear if elav regulation is maintained over extended phylogenetic distances. the transcription factor erect wing (ewg) is a major target of elav in drosophila melanogaster and coordinates metabolic gene expression with regulation of synaptic plasticity. here ...201121705751
a conserved long noncoding rna affects sleep behavior in drosophila.metazoan genomes encode an abundant collection of mrna-like, long noncoding (lnc)rnas. although lncrnas greatly expand the transcriptional repertoire, we have a limited understanding of how these rnas contribute to developmental regulation. here, we investigate the function of the drosophila lncrna called yellow-achaete intergenic rna (yar). comparative sequence analyses show that the yar gene is conserved in drosophila species representing 40-60 million years of evolution, with one of the conse ...201121775470
expression of drosophila virilis retroelements and role of small rnas in their intrastrain transposition.transposition of two retroelements (ulysses and penelope) mobilized in the course of hybrid dysgenesis in drosophila virilis has been investigated by in situ hybridization on polytene chromosomes in two d. virilis strains of different cytotypes routinely used to get dysgenic progeny. the analysis has been repeatedly performed over the last two decades, and has revealed transpositions of penelope in one of the strains, while, in the other strain, the ltr-containing element ulysses was found to be ...201121779346
[localization of the dras1 sequence to polytene chromosomes in sibling species of the drosophila virilis group].drasl gene was mapped by in situ hybridization to polytene chromosomes of several sibling species of the drosophila virilis group and hybrids between them. a 1037 bp fragment of the drasl gene of the d. virilis genome was used as a probe. the gene sequence is localized to the region of the disk 25 a-b on the chromosome 2 of the polytene chromosome map of d. virilis.201121870508
convergent intron loss of mrp1 in drosophila and mosquito species.previous study revealed that the mrp1 gene ortholog dmrp1/cg6214 of drosophila melanogaster contains 12 exons in the coding region. in the current study, the genes of dmrp1/cg6214 from d. melanogaster and drosophila virilis were compared, and the result indicated that d. virilis had an extra intron located in exon 2, implying that intron loss or gain might have occurred at this locus. to track the evolution of the extra intron (intron z), orthologous nucleotide sequences of 37 arthropod species ...201221908794
decrease in juvenile hormone level as a result of genetic ablation of the corpus allatum cells affects the synthesis and metabolism of stress related hormones in drosophila.previous studies have shown that juvenile hormone (jh) regulates dopamine (da) and octopamine (oa) content in drosophila, and we have shown the influence of an increase in jh level on da and oa metabolism in young females of drosophila virilis and drosophila melanogaster. here we investigate the effects of genetic ablation of a subset of cells in the corpusallatum (ca, endocrine gland synthesizing jh) on the da levels and activities of alkaline phosphatase (alp), tyrosine hydroxylase (th), da-de ...201222019561
cold tolerance and cold-induced modulation of gene expression in two drosophila virilis group species with different distributions.the importance of high and low temperature tolerance in adaptation to changing environmental conditions has evoked new interest in modulations in gene expression and metabolism linked with stress tolerance. we investigated the effects of rapid cold hardening and cold acclimatization on the chill coma recovery times of two drosophila virilis group species, drosophila montana and d. virilis, with different distributions and utilized a candidate gene approach to trace changes in their gene expressi ...201222122733
sequence variation in couch potato and its effects on life-history traits in a northern malt fly, drosophila montana.couch potato (cpo) has previously been connected to reproductive diapause in several insect species including drosophila melanogaster, where it has been suggested to provide a link between the insulin signalling pathway and the hormonal control of diapause. in the first part of the study we sequenced nearly 3.6 kb of this gene in a northern drosophila species (drosophila montana) with a robust photoperiodically determined diapause and found several types of polymorphisms along the sequenced area ...201222138635
the role of vertical and horizontal transfer in the evolution of paris-like elements in drosophilid species.the transposable element (te) paris was described in a drosophila virilis strain (virilis species group) as causing a hybrid dysgenesis with other mobile genetic elements. since then, the element paris has only been found in d. buzzatii, a species from the repleta group. in this study, we performed a search for paris-like elements in 56 species of drosophilids to improve the knowledge about the distribution and evolution of this element. paris-like elements were found in 30 species from the dros ...201122527689
the daibam mite element is involved in the origin of one fixed and two polymorphic drosophila virilis phylad inversions.chromosomal inversions can originate from breakage and repair by non-homologous end-joining. nevertheless, they can also originate from ectopic recombination between transposable elements located on the same chromosome inserted in opposite orientations. here, we show that a mite element (daibam), previously involved in the origin of one drosophila americana polymorphic inversion, is also involved in the origin of one fixed inversion between d. virilis and d. americana and another d. americana po ...201222561870
identification of two penelope-like elements with different structures and chromosome localization in kuruma shrimp genome.penelope, originally found as a key element responsible for the hybrid dysgenesis in drosophila virilis, has been widely conserved throughout eukaryotic genomes. in other organisms, they are often referred to as penelope-like elements or ples. in this study, we found two types of ples, designated mjple01 and mjple02, from kuruma shrimp, marsupenaeus japonicus. there was no observed nucleotide similarity between mjple01 and 02, and both elements differed from each other in terms of their structur ...201322825394
comparative motif discovery combined with comparative transcriptomics yields accurate targetome and enhancer predictions.the identification of transcription factor binding sites, enhancers, and transcriptional target genes often relies on the integration of gene expression profiling and computational cis-regulatory sequence analysis. methods for the prediction of cis-regulatory elements can take advantage of comparative genomics to increase signal-to-noise levels. however, gene expression data are usually derived from only one species. here we investigate tissue-specific cross-species gene expression profiling by ...201323070853
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