Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| loss of a paternal chromosome causes developmental anomalies among drosophila hybrids. | hybrids between drosophila virilis and d. lummei suffer from developmental anomalies. previous reports also suggest that these hybrids lose the d. lummei sixth chromosome early in development. genetic and cytological data presented here confirm the loss of the microchromosome from both the soma and the germ-line of these hybrids and provide strong evidence that this loss causes the hybrid developmental anomalies. | 1992 | 1428956 |
| characterization of the progeny of x-ray irradiated males from two drosophila virilis strains differing in genetic instability. | significant effects of x-ray treatment on the increase in the number of phenotypic variations, two visible mutations, and chromosome aberrations were found in the progeny of irradiated males from the d. virilis laboratory stock that is capable of hybrid dysgenesis syndrome induction. this effect is much more pronounced than in the progeny of irradiated males from strong wild-type strains studied. a correlation between genetic instability and chromosome radiosensitivity was outlined. the mechanis ... | 1992 | 1378553 |
| ulysses transposable element of drosophila shows high structural similarities to functional domains of retroviruses. | we have determined the dna structure of the ulysses transposable element of drosophila virilis and found that this transposon is 10,653 bp and is flanked by two unusually large direct repeats 2136 bp long. ulysses shows the characteristic organization of ltr-containing retrotransposons, with matrix and capsid protein domains encoded in the first open reading frame. in addition, ulysses contains protease, reverse transcriptase, rnase h and integrase domains encoded in the second open reading fram ... | 1992 | 1318387 |
| point mutations in the drosophila hairy gene demonstrate in vivo requirements for basic, helix-loop-helix, and wrpw domains. | the drosophila pair-rule gene, hairy (h), encodes a nuclear basic helix-loop-helix (bhlh) protein that regulates embryonic segmentation and adult bristle patterning. in both cases, the h protein behaves as a transcriptional repressor. in this study, we determined the molecular nature of 12 h alleles. one mutation maps within the hlh domain, consistent with h function requiring homodimerization or heterodimerization with other hlh proteins. a second mutation lies in the basic domain, suggesting t ... | 1992 | 1588951 |
| conserved dna binding and self-association domains of the drosophila zeste protein. | the zeste gene product is involved in two types of genetic effects dependent on chromosome pairing: transvection and the zeste-white interaction. comparison of the predicted amino acid sequence with that of the drosophila virilis gene shows that several blocks of amino acid sequence have been very highly conserved. one of these regions corresponds to the dna binding domain. site-directed mutations in this region indicate that a sequence resembling that of the homeodomain dna recognition helix is ... | 1992 | 1732733 |
| [a study of genetic polymorphism of isozymes in natural populations of drosophila virilis in east china]. | a study of genetic variation at est-alpha, est-beta, a my, acph and alpha-gpdh loci in local samples of hefei, wuhu, jiujiang, nanchang, changzhou, fuzhou and quanzhou drosophila virilis population is presented. the employment of standard techniques of polyacrylamide electrophoresis and agarose electrophoresis reveals that the former three loci are highly polymorphic in all these populations. according to the allelic frequency of the 5 loci, a genetic distance between the above-mentioned populat ... | 1992 | 1524853 |
| [isolation of a sequence with characteristics of a mobile element from drosophila virilis cells]. | 1992 | 1334829 | |
| [genetic analysis of differences in dopamine metabolism in two drosophila virilis lines under normal conditions and under heat stress]. | the results of genetic analysis of the differences in dopamine (da) content between two lines of drosophila virilis in response to heat stress are presented. the gene(s) controlling the differences in da content under normal conditions is located on the x-chromosome, and the gene(s) controlling the differences in responsiveness of da system to stress was found to be autosomal. by means of polyacrylamide gel electrophoresis was also examined phenoloxidase activity in these lines under normal cond ... | 1993 | 8370505 |
| morphological evolution of the drosophila virilis species group as assessed by rate tests for natural selection on quantitative characters. | two rate tests for assessing natural selection on quantitative traits are discussed for their usefulness in macroevolutionary and adaptational studies. the underlying assumptions and parameter estimation for the constant-heritability (ch) and mutation-drift-equilibrium (mde) models, which are the bases for these tests, are discussed. the purpose of these rate tests is to determine whether morphological change has occurred either too fast to be explained by neutral drift, which suggests direction ... | 1993 | 28564280 |
| an intraspecific gene duplication polymorphism of the urate oxidase gene of drosophila virilis: a genetic and molecular analysis. | nineteen strains of drosophila virilis from diverse geographic locations were examined by genetic and molecular analyses, revealing (a) 12 strains with a single copy of the urate oxidase (uo) gene per haploid genome and (b) 7 strains with a tandem duplication of the uo locus. the d. virilis strains with the uo duplication appear to have identical restriction maps of this region, implying either a single origin for the duplication or several similar events occurring at a hot spot. on the basis of ... | 1993 | 8336546 |
| regulation of tissue-specific expression of the esterase s gene in drosophila virilis. | the esterase s gene (ests) of drosophila virilis is specifically expressed in the ejaculatory bulbs of males. its sequencing shows similarities between ests product and other esterases of different origin. the transcription of ests in ejaculatory bulbs is at least 2 orders of magnitude higher than in other tissues of males. two promoters, p1 (distal) and p2 (proximal), and two different transcripts were identified. the promoter p2 is used much more efficiently, and in a stringent, tissue-specifi ... | 1993 | 8346032 |
| a combined molecular and cytogenetic approach to genome evolution in drosophila using large-fragment dna cloning. | methods of genome analysis, including the cloning and manipulation of large fragments of dna, have opened new strategies for uniting molecular evolutionary genetics with chromosome evolution. we have begun the development of a physical map of the genome of drosophila virilis based on large dna fragments cloned in bacteriophage p1. a library of 10,080 p1 clones with average insert sizes of 65.8 kb, containing approximately 3.7 copies of the haploid genome of d. virilis, has been constructed and c ... | 1993 | 8486077 |
| the salivary gland chromosomes of drosophila virilis: a cytological map, pattern of transcription and aspects of chromosome evolution. | by combining information from microscopical observation and photography a graphical map of drosophila virilis salivary gland chromosomes was constructed. about 1,560 individual bands are shown and patterns of transcription at about 360 sites are indicated. the application of the map is demonstrated by using genetic, morphological and in situ hybridization data to identify the white-notch regions of d. virilis and drosophila melanogaster as homologous chromosome segments with constant and variabl ... | 1993 | 8149815 |
| domain mapping of tube, a protein essential for dorsoventral patterning of the drosophila embryo. | the tube protein plays an essential role in the signal transduction pathway that establishes dorsoventral polarity in the drosophila melanogaster embryo. characterization of each of four tube mutants revealed a substitution or insertion in the amino-terminal half of the protein. this portion of the tube protein is also evolutionarily conserved, as demonstrated by isolation and sequencing of the drosophila virilis tube gene. moreover, rna microinjection assays and germline transformation experime ... | 1993 | 8253071 |
| translation and fates of the gag protein of 1731, a drosophila melanogaster retrotransposon. | an entire copy of 1731, a drosophila melanogaster retrotransposon, was tagged by fusing in frame its putative gag gene with the reporter lacz sequence. the high transfection efficiency of drosophila virilis cells added to the absence of 1731 in their genome allowed, by combining histochemical staining and immunological detections, the demonstration of the translation of the 1731 gag gene. the gag protein is gathered in virus-like particles. its occurrence in nuclei is consistent with a nuclear l ... | 1993 | 8393808 |
| codon usage bias and base composition of nuclear genes in drosophila. | the nuclear genes of drosophila evolve at various rates. this variation seems to correlate with codon-usage bias. in order to elucidate the determining factors of the various evolutionary rates and codon-usage bias in the drosophila nuclear genome, we compared patterns of codon-usage bias with base compositions of exons and introns. our results clearly show the existence of selective constraints at the translational level for synonymous (silent) sites and, on the other hand, the neutrality or ne ... | 1993 | 8349115 |
| the interaction of bride of sevenless with sevenless is conserved between drosophila virilis and drosophila melanogaster. | an inductive interaction between the sevenless (sev) transmembrane tyrosine kinase receptor and the bride of sevenless (boss) transmembrane ligand is required for the development of the r7 photoreceptor neuron in the compound eye of drosophila melanogaster. the boss protein is proposed to contain a large n-terminal extracellular domain, seven transmembrane segments, and a c-terminal cytoplasmic tail. the boss protein from drosophila virilis (bossvir) retains strong amino acid identity with loss ... | 1993 | 8506350 |
| functional conservation of a glucose-repressible amylase gene promoter from drosophila virilis in drosophila melanogaster. | previous studies have demonstrated that the expression of the alpha-amylase gene is repressed by dietary glucose in drosophila melanogaster. here, we show that the alpha-amylase gene of a distantly related species, d. virilis, is also subject to glucose repression. moreover, the cloned amylase gene of d. virilis is shown to be glucose repressible when it is transiently expressed in d. melanogaster larvae. this cross-species, functional conservation is mediated by a 330-bp promoter region of the ... | 1993 | 8483161 |
| analysis of a fushi tarazu autoregulatory element: multiple sequence elements contribute to enhancer activity. | regulatory sequences or factors involved in the regulation of target genes of drosophila homeodomain proteins are largely unknown. here, we identify sequence elements that are involved in the function of the fushi tarazu (ftz) autoregulatory element ae, a direct in vivo target of the homeodomain protein ftz. a systematic deletion analysis of ae in transgenic embryos defines multiple elements that are redundantly involved in enhancer activity. sequences juxtaposed to ftz binding sites are not str ... | 1993 | 8096173 |
| characterization of downstream elements in a raf-1 pathway. | at the poles of the drosophila embryo, cell fate is established by a pathway that begins with the activation of a membrane-associated tyrosine kinase (the torso gene product); this then leads to activation of a serine/threonine kinase (drosophila raf-1). activated raf-1 then leads, by an undefined mechanism, to the transcriptional activation of the tailless (tll) gene; the tll gene product, itself a transcription factor, subsequently regulates the expression of an array of target genes. to furth ... | 1993 | 8430097 |
| conservation of regulatory elements controlling hairy pair-rule stripe formation. | the hairy (h) gene is one of two pair-rule loci whose striped expression is directly regulated by combinations of gap proteins acting through discrete upstream regulatory fragments, which span several kilobases. we have undertaken a comparative study of the molecular biology of h pair-rule expression in order to identify conserved elements in this complex regulatory system, which should provide important clues concerning the mechanism of stripe formation. a molecular comparison of the h locus in ... | 1993 | 8330529 |
| enhancer of rudimentaryp1, e(r)p1, a highly conserved enhancer of the rudimentary gene. | a hybrid dysgenesis-induced mutation, enhancer of rudimentaryp1 (e(r)p1), is a recessive enhancer of a weak rudimentary mutant phenotype in drosophila melanogaster. the e(r) gene was cloned using p element tagging and localized to region 8b on the x chromosome. it encodes a 1.0-kb and a 1.2-kb transcript. the 1.0-kb transcript is present in both adult males and females, while the 1.2-kb transcript is predominantly found in females. the difference in the lengths of the two e(r) transcripts is cau ... | 1994 | 7896098 |
| comparison of the neuralized genes of drosophila virilis and d. melanogaster. | the neurogenic gene neuralized of drosophila melanogaster is thought to play a role in the determination of cell fate in the embryonic nervous system as well as other tissues during development. to determine which sequences within the neuralized gene encode functionally important domains, we have initiated an interspecific comparison of the neuralized gene of d. virilis and d. melanogaster. in this study we show that several motifs that we have previously identified in the neuralized protein of ... | 1994 | 8001814 |
| drosophila virilis oskar transgenes direct body patterning but not pole cell formation or maintenance of mrna localization in d. melanogaster. | the drosophila melanogaster gene oskar is required for both posterior body patterning and germline formation in the early embryo; precisely how oskar functions is unknown. the oskar transcript is localized to the posterior pole of the developing oocyte, and oskar mrna and protein are maintained at the pole through early embryogenesis. the posterior maintenance of oskar mrna is dependent upon the presence of oskar protein. we have cloned and characterized the drosophila virilis oskar homologue, v ... | 1994 | 7925007 |
| components acting in localization of bicoid mrna are conserved among drosophila species. | substantial insights into basic strategies for embryonic body patterning have been obtained from genetic analyses of drosophila melanogaster. this knowledge has been used in evolutionary comparisons to ask if genes and functions are conserved. to begin to ask how highly conserved are the mechanisms of mrna localization, a process crucial to drosophila body patterning, we have focused on the localization of bcd mrna to the anterior pole of the embryo. here we consider two components involved in t ... | 1994 | 8070663 |
| the bipartite d. melanogaster twist promoter is reorganized in d. virilis. | the pivotal role of twist in mesoderm determination in the drosophila embryo depends upon two processes--the transcriptional activation of twist in the ventrally located mesodermal anlage and the regulation of downstream gene expression by the twist transcription factor. to elucidate the molecular mechanisms involved in these processes, we have compared both the coding and regulatory regions of the twist genes from drosophila melanogaster and drosophila virilis. within the coding region, the bas ... | 1994 | 8068548 |
| synonymous codon usage in drosophila melanogaster: natural selection and translational accuracy. | i present evidence that natural selection biases synonymous codon usage to enhance the accuracy of protein synthesis in drosophila melanogaster. since the fitness cost of a translational misincorporation will depend on how the amino acid substitution affects protein function, selection for translational accuracy predicts an association between codon usage in dna and functional constraint at the protein level. the frequency of preferred codons is significantly higher at codons conserved for amino ... | 1994 | 8005445 |
| evolutionary conservation of the structure and expression of alternatively spliced ultrabithorax isoforms from drosophila. | in drosophila melanogaster, alternatively spliced mrnas from the homeotic gene ultrabithorax (ubx) encode a family of structurally distinct homeoprotein isoforms. the developmentally regulated expression patterns of these isoforms suggest that they have specialized stage- and tissue-specific functions. to evaluate the functional importance of ubx isoform diversity and gain clues to the mechanism that regulates processing of ubx rnas, we have investigated whether the ubx rnas of other insects und ... | 1994 | 7911773 |
| regulatory and coding regions of the segmentation gene hunchback are functionally conserved between drosophila virilis and drosophila melanogaster. | the segmentation gene hunchback (hb) is involved in setting up the anterior-posterior axis of the drosophila embryo. it is expressed maternally and zygotically and it plays a key role in integrating the effects of the anterior and posterior maternal systems. the hb gene from d. virilis has previously been cloned and was shown to be well conserved in its coding region, but less so in its upstream region which shows a more patchy pattern of conserved and diverged sequences. this work deals with th ... | 1994 | 8199047 |
| spalt encodes an evolutionarily conserved zinc finger protein of novel structure which provides homeotic gene function in the head and tail region of the drosophila embryo. | the region specific homeotic gene spalt (sal) of drosophila melanogaster promotes the specification of terminal pattern elements as opposed to segments in the trunk. our results show that the previously reported sal transcription unit was misidentified. based on p-element mediated germ line transformation and dna sequence analysis of sal mutant alleles, we identified the transcription unit that carries sal function. sal is located close to the misidentified transcription unit, and it is expresse ... | 1994 | 7905822 |
| cloning of a structural and functional homolog of the circadian clock gene period from the giant silkmoth antheraea pernyi. | the period (per) gene of drosophila plays an important role in circadian clock function. interestingly, homologs of per have not been cloned outside of dipteran species. using a pcr strategy, we now report the cloning of the cdna of a per homolog from the silkmoth antheraea pernyi. the cdna encodes a protein of 849 amino acids, which shows highest identity (39%) with the per protein of drosophila virilis. stretches of high identity between moth and fly proteins are in the amino terminus, the pas ... | 1994 | 7946353 |
| characterization of the highly conserved tfiia small subunit from drosophila melanogaster. | tfiia is a general transcription factor that modulates class ii transcription initiation in vitro by functionally and physically interacting with tfiid or the derived tata-binding protein (tbp). tfiia was previously purified from human, bovine, rat, and yeast sources and has recently been identified in association with tfiid in drosophila. here, we report the cloning of a cdna encoding the 12.5-kda subunit of tfiia from drosophila melanogaster (dtfiia-s) and the identification of a partial dtfii ... | 1994 | 7929095 |
| [identification and ultrastructural characteristics of retrotransposon tv1 virus-like particles in drosophila virilis cells]. | 1994 | 7858512 | |
| molecular cloning of the drosophila virilis larval glue protein gene lgp-3 and its comparative analysis with other drosophila glue protein genes. | dna comprising the larval glue protein gene lgp-3 of drosophila virilis was isolated from a lambda genomic and a cdna library. the transcription start site, two polyadenylation sites and the boundaries of the single intron were determined. an open reading frame encoding 379 amino acids was found. at the dna level the presence of similar introns and three conserved sequence motifs in the proximal promoters suggest that the gene is related to those of the d. virilis lgp-1 and the d. melanogaster s ... | 1994 | 7918662 |
| songs produced by the females of the drosophila virilis group of species. | females of the drosophila virilis group of species may vibrate their wings during courtship producing songs consisting of trains of successive sound pulses (pulse song) or sinusoidal hums (sine song). in the present study we describe these songs and study their role in courtship using a transition analysis. to find out which songs should be classified as pulse songs and which ones as sine songs, we studied the inheritance of different song types in interspecific f1 hybrids. in only a few species ... | 1994 | 7945156 |
| [tv1--a new family of drosophila virilis retrotransposons]. | a new method for isolation and cloning of functionally active retrotransposons was proposed and tested. the method is based on the hypothesis about the universal character of retrotransposition through reverse transcription. a new retrotransposon family (tvl) was coned from the drosophila virilis genome. a full-length tvl copy was 7 kb. the cell line under consideration contained 500-1000 tvl copies per cell, i.e., it accounted for 0.3% of the genome. tvl rna, detected in the cell culture, was a ... | 1994 | 8045392 |
| [two forms of juvenile-hormone-esterase in drosophila virilis]. | 1994 | 8167594 | |
| secondary courtship songs and inhibitory songs of drosophila virilis-group males. | the males of all drosophila virilis-group species produce primary courtship song; and the males of four of these species also provide secondary courtship song when courting a female. the amount of secondary song and the courtship phase at which it is produced vary according to the species. d. lummei males produce secondary song consisting of successive 12-ms-long sound pulses with 70-ms-long intervals between pulses. d. borealis males produce short and dense pulse trains and d. littoralis and d. ... | 1994 | 8192624 |
| the pvb370 bamhi satellite dna family of the drosophila virilis group and its evolutionary relation to mobile dispersed genetic pdv elements. | the pvb370 bamhi tandemly repeated satellite dna family was isolated and analyzed in eight species of the drosophila virilis group and is probably common to all its members. unexpectedly, the satellite dna family showed similar levels of intra- and interspecific sequence variability. an embl gene-bank search revealed a high degree of similarity between the members of the pvb370 bamhi satellite dna sequence family and the direct terminal repeats of the mobile dispersed genetic pdv elements descri ... | 1995 | 7490775 |
| conserved alternative splicing patterns and splicing signals in the drosophila sodium channel gene para. | we cloned genomic dna corresponding to the drosophila virilis homologue of para, a gene encoding a sodium channel alpha-subunit, and obtained many partial cdna clones from embryos and adults. para protein has been well conserved, and the optional elements at six different sites of alternative splicing in d. melanogaster are present in d. virilis, in addition to one new optional exon. among 31 different splice-types observed in d. virilis, the stage-specific pattern of alternative splicing seen i ... | 1995 | 8536968 |
| diverse transposable elements are mobilized in hybrid dysgenesis in drosophila virilis. | we describe a system of hybrid dysgenesis in drosophila virilis in which at least four unrelated transposable elements are all mobilized following a dysgenic cross. the data are largely consistent with the superposition of at least three different systems of hybrid dysgenesis, each repressing a different transposable element, which break down following the hybrid cross, possibly because they share a common pathway in the host. the data are also consistent with a mechanism in which mobilization o ... | 1995 | 7644536 |
| [genetic analysis of differences in metabolism of juvenile hormone in lines of drosophila virilis resistant and sensitive to heat stress]. | the metabolism of juvenile hormone (jh) in imagos of two drosophila species (d. virilis and d. melanogaster) was studied in the normal state and after short-term heat stress. females of both species respond to stress by a decrease in the activity of jh esterase. this decrease is realized through a decrease in the amount of protein. jh metabolism in males does not change after heat stress. genetic analysis of differences in the activity of dpf-resistant jh esterase in stress-sensitive and stress- ... | 1995 | 7721060 |
| sequence evolution of the gpdh gene in the drosophila virilis species group. | the nucleotide sequence of the gpdh gene from six taxa, d. virilis, d. lummei, d. novamexicana, d. a. americana, d. a. texana and d. ezoana, belonging to the virilis species group was determined to examine details of evolutionary change in the structure of the gpdh gene. the gpdh gene is comprised of one 5' non-translated region, eight exons, seven introns and three 3' non-translated regions. exon/intron organization was identical in all the species examined, but different from that of mammals. ... | 1995 | 8522168 |
| induction of diaphorase-1 by dicoumarol in drosophila virilis larvae. | drosophila diaphorase-1 (dia-1) is an enzyme similar to mammalian dt-diaphorase and is inhibited in vitro by dicoumarol. however, a ten-fold increase in dia-1 activity was observed when third instar drosophila virilis larvae were fed on a diet containing 0.1 m dicoumarol for 48 h. this induction was shown to be dose dependent and immunoprecipitation experiments with dia-1 anti-serum demonstrated an increase in the dia-1 protein level in dicoumarol-treated larvae. the induction of dia1 by dicouma ... | 1995 | 7537551 |
| conservation of structure and expression of the trithorax gene between drosophila virilis and drosophila melanogaster. | the drosophila melanogaster trithorax gene encodes several large rnas which are expressed in complex patterns in the embryo. the d. virilis trithorax gene was isolated and sequenced. it produces a similar to d. melanogaster set of transcripts, and it encodes a protein that shows sequence similarity in several domains which are also conserved in human homologue, all-1/hrx. previous experiments have suggested that a distinct expression domain of trithorax in the posterior region of the embryo is r ... | 1995 | 8555104 |
| conservation and function of the transcriptional regulatory protein runt. | a phylogenetic approach was used to identify conserved regions of the transcriptional regulator runt. alignment of the deduced protein sequences from drosophila melanogaster, drosophila pseudoobscura, and drosophila virilis revealed eight blocks of high sequence homology separated by regions with little or no homology. the largest conserved block contains the runt domain, a dna and protein binding domain conserved in a small family of mammalian transcription factors. the functional properties of ... | 1995 | 7568078 |
| [tyrosine hydroxylase activity in drosophila virilis lines with contrasting stress response and in their f1 hybrids]. | activity of tyrosine hydroxylase (th) was examined in adult flies from stress lines of drosophila virilis resistant and nonresistant to heat and from their hybrids under heat stress and normal conditions. the resistant line was shown to have higher enzyme activity and dominate for this character. gene(s) controlling the level of th activity under normal conditions were not sex-linked. it was shown than 30-min heat stress caused a decrease in th activity; with 120-min stress, the activity increas ... | 1995 | 7607425 |
| high divergence of reproductive tract proteins and their association with postzygotic reproductive isolation in drosophila melanogaster and drosophila virilis group species. | the possible association between gonadal protein divergence and postzygotic reproductive isolation was investigated among species of the drosophila melanogaster and d. virilis groups. protein divergence was scored by high-resolution two-dimensional electrophoresis (2de). close to 500 protein spots from gonadal tissues (testis and ovary) and nongonadal tissues (malpighian tubules and brain) were analyzed and protein divergence was calculated based on presence vs absence. both testis and ovary pro ... | 1995 | 8587107 |
| evolutionary divergence of the cytochrome b5 gene of drosophila. | cytochrome proteins perform a broad spectrum of biological functions ranging from oxidative metabolism to electron transport and are thus essential to all organisms. the b-type cytochrome proteins bind heme noncovalently, are expressed in many different forms and are localized to various cellular compartments. we report the characterization of the cytochrome b5 (cyt-b) gene of drosophila virilis and compare its structure to the cyt-b gene of drosophila melanogaster. as in d. melanogaster, the d. ... | 1995 | 7563130 |
| the segment-polarity gene fused is highly conserved in drosophila. | the segment polarity gene fused (fu) is involved in specification of positional information inside embryonic segments in drosophila melanogaster (dm). the predicted fused (fu) protein contains a serine/threonine kinase domain and a second domain with unknown function. we cloned and sequenced the fu homologous gene from drosophila virilis (dv) and made an interspecific dna sequence comparison to identify regions that have been conserved during evolution. comparison of the predicted amino acid (aa ... | 1995 | 7665071 |
| a relatively small 5' regulatory region of esterase s gene of drosophila virilis determines the specific expression as revealed in transgenic experiments. | expression of the esterase s gene of drosophila virilis was studied in transgenic experiments. truncated genomic copy of this gene including 400 bp of 5' regulatory region was integrated into the genome of drosophila melanogaster. the products of the transferred gene were detected. it was found that strict temporal and tissue specificity of the esterase s gene expression is conserved in transformed flies. the results suggest that this specificity is evidently determined by the regulatory region ... | 1995 | 7639749 |
| the extra sex combs protein is highly conserved between drosophila virilis and drosophila melanogaster. | extra sex combs (esc) is one of the polycomb group genes, whose products are required for long term maintenance of the spatially restricted domains of homeotic gene expression initially established by the products of the segmentation genes. we recently showed that the esc protein contains five copies of the wd motif, which in other proteins has been directly implicated in protein-protein interactions. mutations affecting the wd repeats of the esc protein indicate that they are essential for its ... | 1995 | 8541211 |
| nanos is an evolutionarily conserved organizer of anterior-posterior polarity. | in drosophila melanogaster, nanos functions as a localized determinant of posterior pattern. nanos rna is localized to the posterior pole of the maturing egg cell and encodes a protein that emanates from this localized source. nanos acts as a translational repressor and thereby establishes a gradient of the morphogen hunchback. here we show that the mechanism by which nanos acts in drosophila is a common developmental strategy in dipteran insects. we used cytoplasmic transplantation assays to de ... | 1995 | 7601003 |
| the expression of esterase s gene of drosophila virilis in drosophila melanogaster. | drosophila melanogaster was transformed with the esterase s gene from drosophila virilis. this gene is strongly activated in ejaculatory bulbs of mature males of drosophila virilis. the closely related gene from drosophila melanogaster is activated in ejaculatory ducts. the tissue- and stage-specific expression of incomplete genomic copy of the esterase s gene integrated into the drosophila melanogaster genome is the same as in drosophila virilis. these data show that tissue and stage specificit ... | 1995 | 7875329 |
| conservation of complex expression domains of the pdm-2 pou domain gene between drosophila virilis and drosophila melanogaster. | the closely linked pdm-1 and pdm-2 genes of drosophila are expressed in complex patterns that suggest diverse roles in segmentation and nervous system development. a d. virilis pdm cdna clone was isolated and sequenced. it shares sequence similarity with just the pou domain region of pdm-1, but shares extensive sequence similarity with the largest exon of pdm-2. in situ hybridization to d. virilis embryos shows that virtually all aspects of pdm-2 expression are conserved between d. virilis and d ... | 1995 | 7748782 |
| germline transformation of drosophila virilis with the transposable element mariner. | an important goal in molecular genetics has been to identify a transposable element that might serve as an efficient transformation vector in diverse species of insects. the transposable element mariner occurs naturally in a wide variety of insects. although virtually all mariner elements are nonfunctional, the mos1 element isolated from drosophila mauritiana is functional. mos1 was injected into the pole-cell region of embryos of d. virilis, which last shared a common ancestor with d. mauritian ... | 1996 | 8722788 |
| isolation and sequence of the drosophila virilis 60 a gene, a transforming growth factor-beta superfamily member related to vertebrate bone morphogenetic proteins. | the complete protein-coding region of the drosophila virilis 60 a gene, a member of the transforming growth factor-beta superfamily, was isolated and sequenced. the mature domain of the protein-coding region is 99% identical to the drosophila melanogaster 60 a gene and 73% identical to human bone morphogenetic protein 5. in the pro-domain, a number of large blocks of amino acids are also highly conserved, indicating an important functional role for this portion of the protein as well. in the put ... | 1996 | 8688461 |
| in vivo length oscillations of indirect flight muscles in the fruit fly drosophila virilis. | we have used high-speed video microscopy to measure in vivo length oscillations of the indirect flight muscles of the fruit fly drosophila virilis during tethered flight. the changes in muscle strain were measured by tracking the deformation of the thoracic exoskeleton at the origin and insertion of both the dorsal longitudinal (dlm) and the dorsal ventral (dvm) muscles. the mean peak-to-peak strain amplitudes were found to be 3.5% for the dlms and 3.3% for the dvms, although the strain amplitud ... | 1996 | 9110958 |
| structural and functional conservation of the drosophila doublesex splicing enhancer repeat elements. | we have compared the rna sequences and secondary structures of the drosophila melanogaster and drosophila virilis doublesex (dsx) splicing enhancers. the sequences of the two splicing enhancers are highly divergent except for the presence of nearly identical 13-nt repeat elements (six in d. melanogaster and four in d. virilis) and a stretch of nucleotides at the 5' and 3' ends of the enhancers. in vitro rna structure probing of the two enhancers revealed that the 13-nt repeats are predominantly ... | 1996 | 8849774 |
| 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 |
| identification of cis-acting sequences that control nanos rna localization. | the generation of anterior-posterior polarity during development in drosophila requires the localization of determinant molecules to the anterior and posterior poles of the embryo. localization of the maternally synthesized nanos rna to the posterior pole of the embryo is essential to provide a source for a gradient of nanos protein that directs abdomen formation. nanos rna localization occurs during oogenesis and requires the function of at least nine genes. cis-acting sequences that direct nan ... | 1996 | 8654893 |
| identification and functional characterization of conserved promoter elements from glass: a retinal development gene of drosophila. | the drosophila melanogaster glass transcription factor acts in photoreceptor cell development, glass transcription in the developing eye begins in the morphogenetic furrow. we report a deletion analysis which shows that a 5147 bp fragment can confer near wild-type expression in the developing eye. we completed the sequence of a similar drosophila virilis fragment and comparison of these two genomic sequences reveals seven perfectly conserved sequence elements of 15 bp (or longer). we placed olig ... | 1996 | 8798148 |
| molecular phylogeny and genome evolution in the drosophila virilis species group: duplications of the alcohol dehydrogenase gene. | drosophila virilis is a prominent reference species for comparison with drosophila melanogaster in regard to patterns and mechanisms of molecular and genomic evolution. sequences were determined for 11 adh genes from 8 species of the d. virilis species group, including species from both the virilis phylad and the montana subphylad. the genome of d. virilis contains a 6-kb duplication that includes the entire adh coding region. the pattern of sequence identity within the duplication strongly sugg ... | 1996 | 8583887 |
| dna sequence variation at the period locus reveals the history of species and speciation events in the drosophila virilis group. | the virilis phylad of the drosophila virilis group consists of five closely related taxa: d. virilis, d. lummei, d. novamexicana, d. americana americana and d. americana texana. dna sequences from a 2.1-kb pair portion of the period locus were generated in four to eight individuals from each of the five taxa. we found evidence of recombination and high levels of variation within species. we found no evidence of recent natural selection. surprisingly there was no evidence of divergence between d. ... | 1996 | 8913746 |
| [role of juvenile hormone metabolism in the adaptation of drosophila populations to stressful environmental conditions]. | the effect of heat stress on the system of degradation of juvenile hormone (jh) and on fertility of drosophila virilis and d. melanogaster was studied. in wild-type strains of both species, stress resulted in delay of oviposition and in a decrease in jh hydrolysis and fertility, which lasted for several days after heat treatment. experimental repression of juvenile hormone esterase showed that stress response of the drosophila reproductive system is determined by the decrease in jh hydrolysis. f ... | 1996 | 9026460 |
| genetic analysis of drosophila virilis sex pheromone: genetic mapping of the locus producing z-(11)-pentacosene. | z-(11)-pentacosene, drosophila virilis sex pheromone, is predominant among the female cuticular hydrocarbons and can elicit male courtship behaviours. to evaluate the genetic basis of its production, interspecific crosses between d. novamexicana and genetically marked d. virilis were made and hydrocarbon profiles of their backcross progeny were analysed. the production of z-(11)-pentacosene was autosomally controlled and was recessive. of the six d. virilis chromosomes only the second and the th ... | 1996 | 8772423 |
| recognizing the forest for the trees: testing temporal patterns of cladogenesis using a null model of stochastic diversification. | computer simulations are developed and employed to examine the expected temporal distributions of nodes under a null model of stochastic lineage bifurcation and extinction. these markovian models of phylogenetic process were constructed so as to permit direct comparisons against empirical phylogenetic trees generated from molecular or other information available solely from extant species. for replicate simulated phylads with n extant species, cumulative distribution functions (cdf's) of branchi ... | 1996 | 8754219 |
| incompatibilities between y chromosome and autosomes are responsible for male hybrid sterility in crosses between drosophila virilis and drosophila texana. | crosses between drosophila virilis and d. texana produce viable and fertile f1 males and females. when f1 males are backcrossed to either parental species they also produced fertile sons. however, about one-third of f1 males carrying the d. texana y chromosome are sterile. when fertile f1 males with the d. texana y chromosome are crossed to d. virilis, about three quarters of the sons are sterile. we show that these sterilities result from incompatibilities between the d. texana y chromosome and ... | 1996 | 8801221 |
| germline transformation of drosophila virilis mediated by the transposable element hobo. | a laboratory strain of drosophila virilis was genetically transformed with a hobo vector carrying the miniwhite cassette using a helper plasmid with an hsp70-driven hobo transposase-coding sequence. the rate of transformation was 0.5% per fertile go animal. three transgenic insertions were cloned and characterized and found to be authentic hobo insertions. these results, together with the known widespread distribution of hobo in diverse insect species, suggest that hobo and related transposable ... | 1996 | 8770594 |
| vitellogenetic defects in hybrids of the species pair drosophila virilis and drosophila texana. | in interspecific matings between the species drosophila virilis and drosophila texana, female sterility can be observed in f2 backcross females and in f2 hybrid females. the results presented in this report show that the female sterility, whenever it exists, is due to prevention of vitellogenin synthesis in the fat body, but other abnormalities such as defects with the hybrid ovaries are not excluded. the observation that sterility appears among females from backcrosses suggests that incompatibi ... | 1996 | 8754280 |
| [genetic analysis of differences in alkaline phosphatase activity in two drosophila virilis strains differing in heat stress response]. | genetic control of changes in alkaline phosphatase activity was studied in adult individuals from two strains of drosophila virilis under normal conditions and at a high temperature (38 degrees c). flies from strain 101 responded to the heat shock with a reduction in enzyme activity, whereas flies from strain 147 lacked this response. strains 101 and 147 were shown to differ in alkaline phosphatase activity at a normal temperature. genetic analysis of these differences was performed. they were s ... | 1996 | 8647425 |
| interspecific rna in situ hybridization reveals perinuclear mastermind transcripts in drosophila virilis. | 1996 | 8583901 | |
| trash dna is what gets thrown away: high rate of dna loss in drosophila. | we have recently described a novel method of estimating neutral rates and patterns of spontaneous mutation (petrov et al., 1996). this method takes advantage of the propensity of non-ltr retrotransposable elements to create non-functional, 'dead-on-arrival' copies as a product of transposition. maximum parsimony analysis is used to separate the evolution of actively transposing lineages of a non-ltr element from the fate of individual inactive insertions, and thereby allows one to assess directl ... | 1997 | 9461402 |
| sequence, molecular organization and products of the drosophila virilis homologs of the d. melanogaster nested genes lethal(2) tumorous imaginal discs [1(2)tid] and lethal(2) neighbour of tid [1(2)not]. | in this study, we describe the isolation of the drosophila virilis (dvir) 6201-bp genomic fragment homologous to a 7047-bp genomic region of d. melanogaster (dmel) that harbors the nested genes lethal(2) tumorous imaginal discs (l(2)tid), lethal(2) neighbour of tid (l(2)not) and lethal(2) relative of tid (l(2)rot). the isolated fragment, which maps at the cytogenetic position 50a5 on chromosome 5, carries the dvir homologs of the dmel genes l(2)tid and l(2)not. in both cases, the interspecific c ... | 1997 | 9434170 |
| discordant rates of chromosome evolution in the drosophila virilis species group. | in drosophila, the availability of polytene chromosome maps and of sets of probes covering most regions of the chromosomes allows a direct comparison of the organization of the genome in different species. in this work, we report the localization, in drosophila virilis, d. montana, and d. novamexicana, of > 100 bacteriophage pi clones containing approximately 65 kilobase inserts of genomic dna from d. virilis. each clone hybridizes with a single euchromatic site in either chromosome 1 or chromos ... | 1997 | 9286682 |
| [genetic control of dfp-sensitive juvenile hormone esterase activity in drosophila virilis]. | genetic analysis of differences in the activity of dfp-sensitive juvenile hormone esterase in 24-hour-old d. virilis flies was performed. lines of d. virilis resistant and sensitive to long-term heat stress were analyzed under normal conditions. the level of juvenile hormone hydrolysis by this esterase was higher in the resistant than in the sensitive line. interlinear differences in the enzyme activity were shown to be controlled monogenically or by a block of tightly linked genes. the allele o ... | 1997 | 9378288 |
| [genetic control of drosophila virilis tyrosine decarboxylase activity]. | tyrosine decarboxylase (tdc) activity was studied in flies of two drosophila virilis lines having contrasting response to stress. lines 101 and 147 exhibited different tdc activity. genetic analysis of these differences was performed. tdc activity was shown to be controlled by one gene or a block of tightly linked genes. the gene controlling tdc activity was mapped to one autosome but not to chromosome 2. in line 101, short-term heat stress (38 degrees c, 60 min) resulted in reduction in tdc act ... | 1997 | 9378287 |
| [n-acetylation of biogenic amines in drosophila virilis]. | in adults of two drosophila virilis lines displaying different genetically determined reactions to stress, n-acetyl-transferase (nat) activity against substrates dopamine and octapamine was studied. sexual dimorphism was characteristic of nat activity when octapamine served as a substrate. however, in the case of dopamine, this phenomenon was not found. this suggests that two different enzymes with n-acetyltransferase activities exist in d. virilis. the flies of the studied lines were not shown ... | 1997 | 9289416 |
| tyrosine decarboxylase and dopa decarboxylase in drosophila virilis under normal conditions and heat stress: genetic and physiological aspects. | the activity of tyrosine decarboxylase (tdc) and dopa decarboxylase (ddc) was studied in adults of two lines of drosophila virilis, contrasting in their reaction to stress conditions. differences were found in the activity of both enzymes between individuals of the examined lines. genetic analysis of these differences was made. each of the two enzymes was found to be controlled by a single gene or, possibly, by a block of closely linked genes. the gene responsible for tdc activity is located on ... | 1997 | 9241434 |
| [genomic incompatibility in drosophila virilis sturt. x drosophila lummei hackman hybrids]. | genetic analysis of male sterility in drosophila virilis x d. lummei hybrids was performed. it was shown that hybrid male sterility was caused mainly by incompatibility of sex chromosomes x and y and homozygous chromosome 2 of d. virilis with other autosomes of d. lummei. genes of chromosomes 3 and 5 enhanced sterility whereas genes of chromosome 4 suppressed its development. factors controlling hybrid male sterility were demonstrated to have a recessive type of inheritance. at 17 degrees c, chr ... | 1997 | 9206663 |
| [genetic analysis of differences in dopa decarboxylase activity between two drosophila virilis lines differing in dopamine content]. | activity of dopa decarboxylase (ddc) in two drosophila virilis lines differing in dopamine (da) content was investigated. the activity was shown to be significantly higher in flies with lower da content. a possible reason for this phenomenon is discussed. genetic analysis of the difference showed that ddc activity in drosophila virilis is controlled by single autosomal gene (or a cluster of tightly linked genes). | 1997 | 9244765 |
| [genetic control of the stress response of the system of juvenile hormone metabolism in drosophila virilis]. | metabolism of juvenile hormone (jh) in 11-day-old d. virilis flies from resistant and sensitive lines and in hybrids of these lines was analyzed after short-term heat stress (4 h, 38 degrees c). the level of jh hydrolysis after stress remained constant in the sensitive line, but drastically decreased in the resistant one. between-line differences of the metabolic jh response to stress were shown to be controlled monogenically or by a block of closely linked genes. the allele of the resistant lin ... | 1997 | 9162697 |
| penelope, a new family of transposable elements and its possible role in hybrid dysgenesis in drosophila virilis. | a hybrid dysgenesis syndrome occurs in drosophila virilis when males from an established laboratory strain are crossed to females obtained from the wild, causing the simultaneous mobilization of several different transposable elements. the insertion sequence responsible for the mutant phenotype of a dysgenic yellow allele has been characterized and named penelope. in situ hybridization and southern analyses reveal the presence of more than 30 copies of this element in the p-like parental strain, ... | 1997 | 8990185 |
| modern thoughts on an ancyent marinere: function, evolution, regulation. | the mariner/tc1 superfamily of transposable elements is one of the most diverse and widespread class ii transposable elements. within the larger assemblage, the mariner-like elements (mles) and the tc1-like elements (tles) are distinct families differing characteristically in the composition of the "d,d(35)e" cation-binding domain. based on levels of sequence similarity, the elements in each family can be subdivided further into several smaller subfamilies. mles and tles both have an extraordina ... | 1997 | 9442899 |
| ovarian defects in hybrids of the species pair drosophila virilis and drosophila texana. | in interspecific matings between drosophila virilis and drosophila texana female sterility is observed in f2 hybrid females. a previous study has shown that no vitellogenin synthesis occurs in the fat body of sterile hybrid females. the results presented in this paper show that hybrid ovaries of sterile females transplanted into the abdomens of females of the parental species are not able to develop upon maturity. with few exceptions, the hybrid ovaries remained alive in the host environment, bu ... | 1997 | 9094211 |
| the putative cell cycle gene, enhancer of rudimentary, encodes a highly conserved protein found in plants and animals. | the enhancer of rudimentary gene, e(r), in drosophila melanogaster encodes a protein, er, whose function has been implicated in pyrimidine biosynthesis and the cell cycle (wojcik et al. (1994) genetics 138, 1163-1170). in order to identify conserved regions of the protein and potentially important functional domains, the e(r) gene was cloned and sequenced from two other insects (drosophila virilis and aedes aegypti) and three vertebrates (homo sapiens, mus musculus, and brachydanio rerio) and se ... | 1997 | 9074495 |
| a framework physical map of drosophila virilis based on p1 clones: applications in genome evolution. | the analysis of patterns of genome evolution may help to evaluate the evolutionary forces that shape the composition and organization of the genome. comparisons between the physical maps of divergent species can be used to identify conserved blocks of closely linked genes whose synteny is possibly under selective constraint. we have used in situ hybridization to determine the genomic position of 732 randomly selected clones from a bacteriophage p1 library of drosophila virilis. the resulting map ... | 1997 | 9215559 |
| two evolutionarily conserved repression domains in the drosophila kruppel protein differ in activator specificity. | to identify biologically functional regions in the product of the drosophila melanogaster gene kruppel, we cloned the kruppel homolog from drosophila virilis. both the previously identified amino (n)-terminal repression region and the dna-binding region of the d. virilis kruppel protein are greater than 96% identical to those of the d. melanogaster kruppel protein, demonstrating a selective pressure to maintain the integrity of each region during 60 million to 80 million years of evolution. an a ... | 1997 | 9234738 |
| cdna cloning of three cecropin-like antimicrobial peptides (styelins) from the tunicate, styela clava. | we cloned precursors of three new antimicrobial peptides, styelins c, d and e, from a pharyngeal cdna library of a tunicate, styela clava. preprostyelins resembled dipteran preprocecropins, while the mature domain of styelin c resembled cecropin p1, an antimicrobial peptide purified from the porcine intestine. beginning with the last 6 residues of their signal sequences, styelin c and cecropin 1 from drosophila virilis had 8/11 identical amino acids (72.7%). moreover, 4 of the last 6 residues of ... | 1997 | 9257708 |
| male-predominant carboxylesterase expression in the reproductive system of molluscs and insects: immunochemical and biochemical similarity between mytilus male associated polypeptide (map) and drosophila sex-specific esterase s. | we suggested that sexual differentiation of the reproductive system in gonochoric species of invertebrates can be characterized by common molecular mechanisms in spite of high morphological divergences of reproductive tract organs in different animal groups. the present study focused on this problem and report our observations on biochemical characteristics of male-associated polypeptide (map) identified in the gonad tissue of bivalve molluscs, mytilus galloprovincialis, in comparison to those o ... | 1997 | 9418010 |
| [puff expression in relation to genotype]. | the studies of genotype influence on puff size in salivary gland chromosomes of drosophila virilis (stocks 9, 101, 142, 151) and d. texana (the stock 123) reveal significant differences between the species concerning the structure of puff in the 3-c-6 region at the stage of puparium formation. in reciprocal f1 hybrids the size of the puff was intermediate in comparison with parental forms having a slight maternal effect. the differences in puff size in the 5th chromosome between interspecific hy ... | 1997 | 1218725 |
| transcriptional regulation of the drosophila homeotic gene teashirt by the homeodomain protein fushi tarazu. | the drosophila melanogaster gene teashirt (tsh) is essential for segment identity of the embryonic thorax and abdomen. a deletion 3' to the tsh transcription unit causes the loss of tsh early expression in the even-numbered parasegments, and the corresponding larval cuticular patterns are disrupted. tsh function in the odd-numbered parasegments in these mutants is normal by both criteria. the in vivo activities of genomic fragments from the deleted region were tested in transgenic embryos. a 2.0 ... | 1997 | 9431813 |
| the evolution of small gene clusters: evidence for an independent origin of the maltase gene cluster in drosophila virilis and drosophila melanogaster. | we analyzed a 5,770-bp genomic region of drosophila virilis that contains a cluster of two maltase genes showing sequence similarity with genes in a cluster of three maltase genes previously identified in drosophila melanogaster. the d. virilis maltase genes are designated mav1 and mav2. in addition to being different in gene number, the cluster of genes in d. virilis differs dramatically in intron-exon structure from the maltase genes in d. melanogaster, the transcriptional orientation of the g ... | 1997 | 9335139 |
| a screen for fast evolving genes from drosophila. | in an attempt to quantify the rates of protein sequence divergence in drosophila, we have devised a screen to differentiate between slow and fast evolving genes. we find that over one-third of randomly drawn cdnas from a drosophila melanogaster library do not cross-hybridize with drosophila virilis dna, indicating that they evolve with a very high rate. to determine the evolutionary characteristics of such protein sequences, we sequenced their homologs from a more closely related species (drosop ... | 1997 | 9275195 |
| twist-mediated activation of the nk-4 homeobox gene in the visceral mesoderm of drosophila requires two distinct clusters of e-box regulatory elements. | nk-4, also called msh2 and tinman, encodes a homeodomain transcription factor that is required for the development of the dorsal mesoderm and its derivatives in the drosophila embryo. genetic analyses indicate that nk-4 resides downstream of the mesodermal determinant twist, which encodes a basic helix-loop-helix-type transcription factor. however, the regulation of nk-4 by twist remains poorly understood. using expression assays in cultured cells and transgenic flies, we show that two distinct ... | 1997 | 9211899 |
| evolutionary conservation of regulatory strategies for the sex determination factor transformer-2. | sex determination in drosophila melanogaster is regulated by a cascade of splicing factors which direct the sex-specific expression of gene products needed for male and female differentiation. the splicing factor tra-2 affects sex-specific splicing of multiple pre-mrnas involved in sexual differentiation. the tra-2 gene itself expresses a complex set of mrnas generated through alternative processing that collectively encode three distinct protein isoforms. the expression of these isoforms differ ... | 1997 | 9111363 |
| a drosophila melanogaster hobo-white(+) vector mediates low frequency gene transfer in d. virilis with full interspecific white(+) complementation. | transformation of a drosophila virilis white mutant host strain was attempted using a hobo vector containing the d. melanogaster mini-white(+) cassette (h[w(+), hawn]) and an unmodified or heat shock regulated hobo transposase helper. two transformant lines were recovered with the unmodified helper (hfl1), one containing only the white(+) marked vector, and a sibling line containing the vector as well as an hfl1 helper integration. an approximate total transformation frequency of 1% is deduced. ... | 1997 | 9099580 |
| identification and characterization of the cecropin antibacterial protein gene locus in drosophila virilis. | cecropin is a type of antibacterial peptide that is synthesized in response to infection and has been characterized in many insect species and one mammal. the cecropin locus of drosophila melanogaster also contains the gene andropin, which has been identified only in this species and encodes a male-specific antibacterial peptide. as a first step in studying the molecular evolution of the cecropin and andropin genes among drosophila species, we have isolated genomic clones that cover the cecropin ... | 1997 | 9060393 |
| comparison of the gaga factor genes of drosophila melanogaster and drosophila virilis reveals high conservation of gaga factor structure beyond the btb/poz and dna-binding domains. | as a member of the trithorax-group, the trithorax-like (trl) gene of drosophila melanogaster contributes to the expression of homeotic genes and many other genes. trl encodes different isoforms of the gaga factor which is thought to act as an "antirepressor" of transcription by remodelling chromatin structure and thereby rendering control regions accessible for transcriptional activators. a more global role of the gaga factor in chromatin structure and function is suggested by various phenotypes ... | 1998 | 9799425 |
| conservation of read-through transcription of the drosophila serendipity genes during evolution is gratuitous. | the drosophila melanogaster serendipity (sry) genes sry alpha and sry beta, which code for unrelated proteins and functions, are transcribed both as monocistronic (sry alpha, srv beta) and dicistronic (sry beta-sry alpha) polyadenylated transcripts, the three types of transcripts being differentially expressed throughout development. we show here that, while the sry gene cluster is conserved in two other distantly related drosophila species, sry beta-sry alpha dicistronic transcription is observ ... | 1998 | 9790579 |