| effect of the drosophila endosymbiont spiroplasma on parasitoid wasp development and on the reproductive fitness of wasp-attacked fly survivors. | in a previous study, we showed that spiroplasma, a maternally transmitted endosymbiotic bacterium of drosophila hydei, enhances larval to adult survival of its host when exposed to oviposition attack by the parasitoid wasp leptopilina heterotoma. the mechanism by which spiroplasma enhances host survival has not been elucidated. to better understand this mechanism, we compared the growth of wasp larvae in spiroplasma-infected and uninfected hosts. our results indicate that wasp embryos in spiropl ... | 2011 | 22912533 |
| microsatellite markers isolated from drosophila hydei. | we isolated and characterized 10 polymorphic microsatellite loci in drosophila hydei. the number of alleles per locus ranged from 3 to 8 (n = 23 individuals). polymorphic information content ranged from 0.316 to 0.750 and observed heterozygosity from 0.261 to 0.913. these markers will be valuable in studies of sexual selection and parental investment in d. hydei. | 2009 | 21564754 |
| germline transgenesis and insertional mutagenesis in the ascidian ciona intestinalis. | stable transgenesis is a splendid technique that is applicable to the creation of useful marker lines, enhancer/gene traps, and insertional mutagenesis. recently, transposon-mediated transformation using a tc1/mariner transposable element minos has been reported in two ascidians: ciona intestinalis and c. savignyi. the transposon derived from an insect, drosophila hydei, has high activity for excision in ciona embryos and transposition in their genome. as much as 37% of minos-injected c. intesti ... | 2007 | 17342755 |
| on the phylogeny of the drosophila hydei subgroup: new insights from combined analyses of nuclear and mitochondrial data. | | 2007 | 17292635 |
| magnesium transport through the basal plasma membrane of larval malpighian tubules of drosophila hydei studied by electron probe x-ray microanalysis. | magnesium besides calcium is the most important excretion product. in the anterior malpighian tubules of drosophila, excretion of magnesium takes place via the hindgut by proteoglycan containing concretions. this study reports on magnesium transport through the basal plasma membrane of the principal cells of the proximal segment of the anterior malpighian tubules. measurements by electron probe x-ray microanalysis indicate the existence of two antiporters which transfer magnesium in still unknow ... | 2002 | 12030418 |
| molecular evolution and phylogeny of the buzzatii complex (drosophila repleta group): a maximum-likelihood approach. | the buzzatii complex of the mulleri subgroup (drosophila repleta group) consists of three clusters of species whose evolutionary relationships are poorly known. we analyzed 2,085 coding nucleotides from the xanthine dehydrogenase (xdh:) gene in the 10 available species of the complex and drosophila mulleri and drosophila hydei. we adopted a statistical model-fitting approach within the maximum-likelihood (ml) framework of phylogenetic inference. we first modeled the process of nucleotide substit ... | 2000 | 10889224 |
| correlated response in reproductive and life history traits to selection on testis length in drosophila hydei. | flies in the genus drosophila have undergone striking evolutionary divergence in the size and number of sperm produced. based on comparative studies of sperm length, testis length, and other reproductive and life history traits, including body size, age at first reproduction, and the number of sperm produced, macroevolutionary trade-offs resulting from the need to produce high-investment testes have been postulated. to understand better the microevolutionary processes underlying these interspeci ... | 2000 | 10849065 |
| mega-introns in the dynein gene dhdhc7(y) on the heterochromatic y chromosome give rise to the giant threads loops in primary spermatocytes of drosophila hydei. | the heterochromatic y chromosomes of several drosophila species harbor a small number of male fertility genes (fertility factors) with several unusual features. expression of their megabase-sized loci is restricted to primary spermatocytes and correlates with the unfolding of species-specific lampbrush loop-like structures resulting from huge transcripts mainly derived from clusters of loop-specific y chromosomal satellites. otherwise, there is evidence from genetic mapping and biochemical exper ... | 2000 | 10655227 |
| functional analysis of an eye specific enhancer of the eyeless gene in drosophila. | the development of the drosophila compound eye requires the function of a set of evolutionarily conserved genes. among these, the drosophila pax-6 gene eyeless (ey) plays a major role. ey has been considered a master control gene of eye development in the animal kingdom because targeted expression of ey and vertebrate as well as invertebrate homologs lead to the formation of ectopic eyes in drosophila. we demonstrate that an intron of the ey gene contains an enhancer that regulates the eye speci ... | 1999 | 9892673 |
| naturally occurring testis-specific histone h3 antisense transcripts in drosophila. | while analysing the transcription of the cluster of cell-cycle regulated histone genes in drosophila hydei, we have found transcripts spanned both histone h3 and h4 genes and were antisense for histone h3. as the two histone genes are in opposite orientation, these transcripts contained the sense strand of the histone h4 gene. such transcripts were present in both poly(a)+ and poly(a)- rna fractions. the polyadenylated molecules contained a poly(a) tail at the 3' end of the stem-loop structure, ... | 1997 | 9364435 |
| molecular cloning of a family of xenobiotic-inducible drosophilid cytochrome p450s: evidence for involvement in host-plant allelochemical resistance. | cytochrome p450s constitute a superfamily of genes encoding mostly microsomal hemoproteins that play a dominant role in the metabolism of a wide variety of both endogenous and foreign compounds. in insects, xenobiotic metabolism (i.e., metabolism of insecticides and toxic natural plant compounds) is known to involve members of the cyp6 family of cytochrome p450s. use of a 3' race (rapid amplification of cdna ends) strategy with a degenerate primer based on the conserved cytochrome p450 heme-bind ... | 1997 | 9380713 |
| a graphical method for analysing the dynamics of three-species systems. | we report a series of experiments with three competing species and a novel graphical analysis that explores the dynamics of this simple multi-species system. the three competing species (drosophila hydei, d. immigrans and d. virilis) were maintained in five very large cages, on a natural fruit resource. the analytic method involved constructing a "dynamic surface", by interpolation, from the population trajectories. within the dynamic surface constructed from the five experiments a small "equili ... | 1997 | 28308114 |
| cis-dichloro(alpha,omega-diamino carboxylate ethyl ester)palladium(ii) as palladium(ii) versus platinum(ii) model anticancer drugs: synthesis, solution equilibria of their aqua, hydroxo, and/or chloro species, and in vitro/in vivo dna-binding properties. | cis-dichloro(d,l-2,3-diaminopropionate ethyl ester)palladium(ii), cis-[pd(etdap)cl(2)] (i), and cis-dichloro(d,l-2,4-diaminobutyrate ethyl ester)palladium(ii), cis-[pd(etdab)cl(2)] (ii), were synthesized and characterized by elemental analysis, ir spectroscopy, and tg-dta thermal analysis. the equilibrium model and log beta(pqr) constants of hydrolytic species of i and ii were also investigated by potentiometric methods (i = 0.15 m (naclo(4)) and 37 degrees c). aqueous solutions of cis-[pd(etdaa ... | 1997 | 11669784 |
| molecular systematics of the drosophila hydei subgroup as inferred from mitochondrial dna sequences. | the phylogeny of the drosophila hydei subgroup, which is a member of the d. repleta species group, was inferred from 1,515 base pairs of mitochondrial dna sequence of the cytochrome oxidase subunits i, ii, and iii. four of the seven species in the subgroup were examined, which are placed into two taxonomic complexes: the d. bifurca complex (d. bifurca and d. nigrohydei) and the d. hydei complex (d. hydei and d. eohydei). both complexes appear to be monophyletic, although the d. bifurca complex i ... | 1996 | 8703094 |
| transcription of gypsy elements in a y-chromosome male fertility gene of drosophila hydei. | we have found that defective gypsy retrotransposons are a major constituent of the lampbrush loop pair nooses in the short arm of the y chromosome of drosophila hydei. the loop pair is formed by male fertility gene q during the primary spermatocyte stage of spermatogenesis, each loop being a single transcription unit with an estimated length of 260 kb. using fluorescent in situ hybridization, we show that throughout the loop transcripts gypsy elements are interspersed with blocks of a tandemly r ... | 1996 | 8852843 |
| strukturdifferenzierungen in y-chromosom von drosophila hydei: the unique morphology of the y chromosomal lampbrush loops threads results from 'coaxial shells' formed by different satellite-specific subregions within megabase-sized transcripts. | the results of pulsed-field gel electrophoresis (pfge) analysis and two-colour transcript fluorescence in situ hybridization (fish) for the three threads-specific dna satellites ylii, yli and rally are in support of long-range clustering of these sequence families within the subterminal region on the long arm of the y chromosome of drosophila hydei. on the basis of the linear arrangement of at least four extended clusters of satellite-specific sequences, the loop morphology of wild-type and seve ... | 1996 | 8785614 |
| minor-myosin, a novel myosin isoform synthesized preferentially in drosophila testis is encoded by the muscle myosin heavy chain gene. | searching for structural proteins involved in spermatogenesis of drosophila, we found a novel myosin isoform in the testis of drosophila hydei and d. melanogaster. the transcript encoding this isoform, which we called 'minor-myosin', initiates within the intron between exons 12 and 13 of the muscle myosin heavy chain (mmhc) gene. minor-myosin contains a common myosin tail but no ordinary myosin head domain. instead, it has a short n-terminal domain which displays similarity with the n-termini of ... | 1995 | 7669694 |
| [unusually prolonged extrachromosomal stability of plasmids containing fragments of retrotransposon mdg4, after transfection of drosophila hydei cell cultures]. | | 1995 | 7735112 |
| tandemly arranged repeats of a novel highly charged 16-amino-acid motif representing the major component of the sperm-tail-specific axoneme-associated protein family dhmst101 form extended alpha-helical rods within the extremely elongated spermatozoa of drosophila hydei. | we have previously reported that the sperm-tail-specific proteins in drosophila hydei, encoded by the small dhmst101 gene family, contained several tandem repeats of a novel highly charged, well-conserved cysteine-containing motif of 16 amino acids, kkkcaeaakkekeaae [neesen, j., bünemann, h. & heinlein, u. a. o. (1994) dev. biol. 162, 414-425] and suggested that this motif might be important in the structural and functional integrity of the sperm tail. we tested this suggestion by examining stru ... | 1994 | 7957199 |
| degenerating gypsy retrotransposons in a male fertility gene on the y chromosome of drosophila hydei. | during the evolution of the y chromosome of drosophila hydei, retrotransposons became incorporated into the lampbrush loop pairs formed by several of the male fertility genes on this chromosome. although insertions of retrotransposons are involved in many spontaneous mutations, they do not affect the functions of these genes. we have sequenced gypsy elements that are expressed as constituents of male fertility gene q in the lampbrush loop pair nooses. we find that these gypsy elements are all tr ... | 1994 | 7807535 |
| another way of being anisogamous in drosophila subgenus species: giant sperm, one-to-one gamete ratio, and high zygote provisioning. | it is generally assumed that sexes in animals have arisen from a productivity versus provisioning conflict; males are those individuals producing gametes necessarily small, in excess, and individually bereft of all paternity assurance. a 1- to 2-cm sperm, 5-10 times as long as the male body, might therefore appear an evolutionary paradox. as a matter of fact, species of drosophila of the drosophila subgenus differ from those of other subgenera by producing exclusively sperm of that sort. we repo ... | 1994 | 7937962 |
| transcription of repetitive dna sequences in the lampbrush loop pair nooses formed by sterile alleles of fertility gene q on the y chromosome of drosophila hydei. | the y chromosomal lampbrush loop-forming male fertility genes of drosophila consist mainly of repetitive dna sequences that do not code for proteins. we investigated whether differences in the transcription of these sequences can be detected in male-sterile alleles of male fertility gene q, which forms the loop pair nooses. the loop consists, for approximately two-thirds, of repeats of the y-specific ay1 family of repetitive dna sequences. of the remaining one-third, at least one-half is represe ... | 1994 | 7969035 |
| representative and efficient cloning of satellite dnas based on pfge pre-fractionation of restriction digests of genomic dna. | using dna from drosophila hydei kun-dh-33 cells we describe an efficient method for selective and representative cloning of complex mixtures of satellite dnas from eukaryotic genomes. effective separation of satellite dna from the bulk of all other sequences it obtained by fractionation of high molecular weight dna by pfge after treating it with '6 bp' restriction enzymes. since extended clusters of tandemly arranged, so called simple sequence, repeats are inert to cleavage by most '6 bp' restri ... | 1994 | 7963251 |
| the drosophila hydei gene dhmst101(1) encodes a testis-specific, repetitive, axoneme-associated protein with differential abundance in y chromosomal deletion mutant flies. | to understand the effect of the megabase-sized, y chromosomal fertility genes on different stages of spermatogenesis in drosophila hydei, an immunoscreening was performed to search for testis-specific protein-encoding cdnas. the array of isolated clones contained cdna sequences derived from a gene on chromosome 5 at 101bc. the gene, dhmst101(1), is a member of a small gene family and is specifically expressed in adult testis tissue. the mrna encodes a protein of 344 amino acids with a deduced ap ... | 1994 | 8150205 |
| a telomere-like satellite (gggtcat)n comprises 4% of genomic dna of drosophila hydei and is located mainly in centromeric heterochromatin of all large acrocentric autosomes. | we describe the isolation and analysis of a g+c-rich telomere-like (gggtcat)n satellite of drosophila hydei. gggtcat-specific clones were obtained by a combination of restriction enzyme digestion and fractionation of d. hydei dna by pulsed-field gel electrophoresis (pfge). high-molecular-weight dna (> 50 kb) was recovered from gels, sheared by sonication and cloned into the pbs plasmid vector. the results of pfge analysis, quantitative dot blot measurements and fluorescence in situ hybridization ... | 1993 | 8299961 |
| localization of the lampbrush loop pair nooses on the y chromosome of drosophila hydei by fluorescence in situ hybridization. | we have used fluorescence in situ hybridization to map the positions of the different repetitive dna sequences from the region forming the lampbrush loop pair nooses on the y chromosome of drosophila hydei. this region harbours a megabase cluster of tandemly organized repeats of the y-specific ay1 family and a megabase cluster of tandem repeats of the related y-specific ysi family. in addition, ay1 repeats also occur in short blocks that are interspersed by other repetitive dna sequences that we ... | 1993 | 8243166 |
| partial reconstruction of the lampbrush loop pair nooses on the y chromosome of drosophila hydei. | we present the analysis of genomic dna fragments that were isolated as potential segments of the lampbrush loop pair nooses on the short arm of the y chromosome of drosophila hydei. more than 300 kb of dna were recovered in bamhi lambda and cosmid clone groups. this dna is composed of the y-specific ay1 family of repetitive dna sequences, and of other repetitive dna sequences, which at least in part are also located elsewhere in the genome (y-associated sequences). two additional classes of dna ... | 1993 | 8243165 |
| genetic heterogeneity increases viability in competing groups of drosophila hydei. | | 1993 | 28567895 |
| heterogeneous distribution of elemental contents in the larval malpighian tubules of drosophila hydei: x-ray microanalysis of freeze-dried cryosections. | the elements na, cl and k are distributed heterogeneously in the larval cells of the four malpighian tubules of drosophila hydei. elemental gradients are steeper when they are related to the dry weight in comparison to the weight of water. the high contents of na, cl and k in the cytoplasm close to the basal plasma membrane differ significantly from the low values found in the neighboring basal "labyrinth" and in the intermediate cytoplasm. elemental contents (k, cl) increase from the intermedia ... | 1993 | 8339320 |
| low codon bias and high rates of synonymous substitution in drosophila hydei and d. melanogaster histone genes. | we have evaluated codon usage bias in drosophila histone genes and have obtained the nucleotide sequence of a 5,161-bp d. hydei histone gene repeat unit. this repeat contains genes for all five histone proteins (h1, h2a, h2b, h3, and h4) and differs from the previously reported one by a second ecori site. these d. hydei repeats have been aligned to each other and to the 5.0-kb (i.e., long) and 4.8-kb (i.e., short) histone repeat types from d. melanogaster. in each species, base composition at sy ... | 1993 | 8487638 |
| towards a physical map of the fertility genes on the heterochromatic y chromosome of drosophila hydei: families of repetitive sequences transcribed on the lampbrush loops nooses and threads are organized in extended clusters of several hundred kilobases. | the understanding of structure and function of the so-called fertility genes of drosophila is very limited due to their unusual size--several megabases--and their location on the heterochromatic y chromosome. since mapping of these genes has mainly been done by classical cytogenetic analyses using a small number of cytologically visible lampbrush loops as the sole markers for particular fertility genes, the resolution of the genetic map of the y chromosome is restricted to 3-5 mb. here we demons ... | 1992 | 1465096 |
| constructing balancer chromosomes for genetic screens in drosophila hydei. | we used a screen for maternally generated late embryonic lethals as a new method for the isolation of inversions that are suitable for the balancing of mutations in drosophila hydei. the recovery of several inversions by this method demonstrates that female meiosis in d. hydei apparently differs from meiosis in female d. melanogaster, since in d. hydei the defective chromosomes which are generated by a single crossing-over within a paracentric inversion can be recovered via the egg nucleus. in a ... | 1992 | 24202759 |
| minos, a new transposable element from drosophila hydei, is a member of the tc1-like family of transposons. | | 1991 | 1661410 |
| spermatogenesis in drosophila. a genetic approach to cellular and subcellular differentiation. | y chromosomal fertility genes are essential for spermatogenesis, but those genes which code for major structural components of the spermatozoon and those controlling sperm morphogenesis must be located on a different chromosome. in the past, it had been questioned whether it would be possible to achieve a meaningful classification of male sterile mutations by light microscopy. i now show, however, that comparison of 244 autosomal male sterile mutants of drosophila hydei with 400 similar mutants ... | 1991 | 1802704 |
| genetic and cytogenetic analysis of the "th-ps" region of the y chromosome of drosophila hydei: evidence for dual functions of the lampbrush loop-forming fertility genes? | two competing hypotheses have been proposed for the function of the y chromosomal fertility factors in drosophila, which form giant lampbrush loops during the primary spermatocyte stage. the first hypothesis suggests a conventional coding function, the second proposes an unconventional gene function mediated through protein binding by nascent transcripts. therefore, we studied the genetics and cytogenetics of the two y chromosomal fertility genes a and c of drosophila hydei (which form the lampb ... | 1991 | 2062310 |
| binding affinity of leucine-containing chromatin proteins to the polytene x chromosome of drosophila hydei and its significance. | association of newly synthesised non-histone chromosomal protein to the polytene x chromosome of larval salivary glands of d. hydei has been examined by autoradiographic procedure using 3h-leucine. it has been observed that 3h-leucine labelling pattern is inhibited in presence of puromycin. results further reveal that there is a reasonable concordance between the binding affinity of newly synthesized protein on the single x chromosome of the male and paired x's of the female. a sitewise analysis ... | 1991 | 1874548 |
| during drosophila spermatogenesis beta 1, beta 2 and beta 3 tubulin isotypes are cell-type specifically expressed but have the potential to coassemble into the axoneme of transgenic flies. | alpha and beta tubulins exist in a number of different isotypes with distinct expression patterns during development. we have shown by immunofluorescent staining that beta 1, beta 2 and beta 3 tubulins are distributed very specifically in the testes of drosophila. beta 3 tubulin is present exclusively in cytoplasmic microtubules of cells somatic in origin, while the beta 1 isotype is localized in the somatic cells and in early germ cells of both the microtubules of the cytoskeleton as well as in ... | 1991 | 2032541 |
| characterization of the structure and evolution of the adh region of drosophila hydei. | drosophila of the repleta group have a duplication of the gene which encodes alcohol dehydrogenase (adh). we report the nucleotide sequence of an 8.4-kb region of genomic dna of drosophila hydei which includes the entire adh region. analysis of this sequence reveals similarity in organization to the adh region of drosophila mojavensis and drosophila mulleri of the mulleri subgroup, with three genes ordered 5' to 3', adh-psi, adh-2, adh-1. deletion of a nucleotide in the second codon of each pseu ... | 1991 | 2004708 |
| poly[d(c-a)].poly[d(g-t)] is highly transcribed in the testes of drosophila hydei. | microdissection of the lampbrush loops "threads" and "pseudonucleolus" of y chromosomes from primary spermatocytes of drosophila hydei and subsequent microcloning of the dna yielded several recombinant dna clones which cross-hybridized in screening the different clone banks. by dna sequencing we found that the inserts of these cross-hybridizing clones contain blocks of poly[d(c-a].poly[d(g-t)]. testis rna contains a large fraction of transcripts with this simple repeated nucleotide sequence. wit ... | 1990 | 2129287 |
| mass dense vacuoles in drosophila malpighian tubules contain zinc, not sodium. a reinvestigation by x-ray microanalysis of cryosections. | the intracellular storage of zinc in malpighian tubules of drosophila hydei was studied by x-ray microanalysis of freeze-dried cryosections. mass dense vacuoles in the proximal region of the anterior larval malpighian tubule cells were found to accumulate zinc, not sodium. the zinc content was enhanced considerably after addition of zinc to the food of the larvae. zinc-containing vacuoles were also found after pupation. after starvation of larvae in sea water, na was detected in these vacuoles i ... | 1990 | 2081540 |
| the heat shock protein hsp70 binds in vivo to subregions 2-48bc and 3-58d of the polytene chromosomes of drosophila hydei. | multiple interactions of members of the hsp70 family with cellular components have already been described. we present, however, the first evidence that upon heat shock treatment hsp70 molecules interact with specific chromosomal subdivisions of the polytene chromosomes of drosophila hydei. after a heat shock treatment of 20 min the protein binds to subdivision 3-58d1 and to the heat shock inducible subdivisions 2-48b3-6 and 2-48c1-2. hsp70 molecules were also observed in subdivision 3-58d1 durin ... | 1990 | 2265568 |
| molecular cloning of a drosophila potential z-dna forming sequence hybridizing in situ to a developmentally regulated subdivision of the polytene chromosomes. | we describe the selection of a group of plasmids with potential to form z-dna, from libraries of drosophila hydei nuclear dna using anti z-dna monoclonal (22) or polyclonal (10c) antibodies. the supercoiled closed circular forms of most of the selected recombinant plasmids from the 10c z-dna library show affinity to the polyclonal 10c antibody as indicated by dna binding assays. one of these plasmids, pf17, was selected for further study. the insert in this plasmid adopts the z conformation at b ... | 1989 | 2473437 |
| an abundant testis rna species shows sequence similarity to y chromosomal and other genomic sites in drosophila hydei. | a cdna clone bank was constructed from testis poly(a)+ rna of drosophila hydei and screened for clones which hybridize to y chromosomal dna sequences. the insert of clone cdht14 hybridizes to a family of repeated dna sequences with members distributed within the y chromosome and elsewhere in the genome. this type of sequence has earlier been described as the y-associated class of dna. southern blot analysis of dna from different wild-type strains of d. hydei suggests that members of the t14 fami ... | 1989 | 2468992 |
| natural selection and ribosomal dna in drosophila. | natural populations of drosophila mercatorum are variable for the number of x-linked 28s ribosomal genes bearing a 5-kilobase insert. a separate polymorphic x-linked gene controls whether 28s repeats bearing the insert are preferentially underreplicated during the formation of polytene tissue. female flies having at least a third of their 28s genes bearing the insert and lacking the ability to preferentially underreplicate inserted repeats display the abnormal abdomen syndrome. the syndrome is c ... | 1989 | 2556326 |
| retrotransposon-like sequences are expressed in y chromosomal lampbrush loops of drosophila hydei. | the dna sequence family micropia consists of repeated dna sequences that occur dispersed in the genome of drosophila hydei. members of this dna sequence family were recovered from two recombinant dna clone banks obtained by microdissection of the two y chromosomal lampbrush loop threads and pseudonucleolus from primary spermatocyte nuclei. nucleotide sequence analysis of two of the recombinant dna clones revealed homology to the dna region coding for a reverse transcriptase-like protein in retro ... | 1988 | 2463366 |
| structure and function of y chromosomal dna. i. sequence organization and localization of four families of repetitive dna on the y chromosome of drosophila hydei. | the sequence organization of four different families of y chromosomal repetitive dna is characterized at three levels of spatial extension along the y chromosome of drosophila hydei. at the lowest level of resolution, dna blot analysis of y chromosomal fragments of different lengths and in situ hybridization experiments on metaphase chromosomes demonstrate the clustering of each particular sequence family within one defined region of the chromosome. at a higher level of resolution, family specif ... | 1988 | 3349874 |
| structure and function of y chromosomal dna. ii. analysis of lampbrush loop associated transcripts in nuclei of primary spermatocytes of drosophila hydei by in situ hybridization using asymmetric rna probes of four different families of repetitive dna. | psp64/65 subclones of four different families of repetitive sequences on the y chromosome of drosophila hydei were used for in vitro synthesis of labelled rna. pairs of rna probes of opposite strand polarity were employed to analyse rnas transcribed on, or associated with, various y chromosomal lampbrush loops in nuclei of primary spermatocytes of d. hydei. the results of rna filter analysis and in situ hybridization experiments can be generalized as follows: (1) y-specific transcripts are heter ... | 1988 | 2450723 |
| z-dna in transcriptionally active chromosomes. | due to the striking correlation between the distribution of transcriptionally active subdivisions of the polytene chromosomes and z-dna, we have addressed the question of whether the z-dna configuration exists in native, transcriptionally active chromosomes of drosophila hydei prepared without interference by procedures known to induce the b to z conformation. our experiments indicate that z-dna forms are present in a specific set of sites on the native chromosomes. they occur on interbands and ... | 1987 | 3470742 |
| autosomal control of lampbrush-loop formation during spermatogenesis in drosophila hydei by a gene also affecting somatic sex determination. | the y chromosome of drosophila hydei carries information that is necessary for the development of the spermatozoa. in primary spermatocytes y chromosomal genes become active: five of the male fertility factors form giant lampbrush loops. our prior work indicated interactions between the y chromosomal genes and autosomal loci. it is of interest to identify loci regulating the activity of the y chromosomal genes. we, therefore, screened a total of about 14,000 chromosomes (x, 2, 3 and 4) for mutat ... | 1987 | 28305466 |
| functional analysis of the transcriptional control regions of the copia transposable element. | the introduction of copia-based vectors in drosophila hydei cells results in their high-level transient expression and the subsequent establishment of stably transformed cell lines containing multiple copies of vector integrated into host genomic dna. using transformation frequency and transient expression analysis as assays of promoter strength, we have defined the regions of copia essential for expression. we find that the essential sequences reside within the long terminal repeat, but 3' to t ... | 1986 | 16453706 |
| histones and histone acetylation during the embryonic development of drosophila hydei. | histones and histone acetylation have been investigated during three stages of drosophila hydei embryogenesis--early gastrula, late gastrula and organogenesis. no essential changes in the electrophoretic pattern of the histones have been revealed during the stages examined. however, we established an enhanced level of [14c]acetate incorporation at the time of extensive gene activation during gastrulation as well as some quantitative differences in the pattern of acetylation during gastrula and o ... | 1986 | 3757037 |
| origin and evolution of the transcribed repeated sequences of the y chromosome lampbrush loops of drosophila hydei. | the molecular evolution and patterns of conservation of clones from four y chromosome lampbrush loops of drosophila hydei were investigated. each loop contains a discrete family of transcribed repeats that are only slightly conserved even in the hydei subgroup species. sequencing of clones from the four d. hydei loops indicates that all transcribed repeats evolved from a+t-rich elements of the genome. evidence is presented that suggests a y-specific family evolved as a result of the transpositio ... | 1986 | 16593641 |
| isolation of y-chromosomal repetitive dna sequences of drosophila hydei via enrichment of chromosome-specific sequences by heterogeneous hybridization between female and male dna. | male or female dna of drosophila hydei was sheared by sonication, denatured, reannealed to different c0t-values and fractionated by hydroxyapatite. the highly repetitive, moderately repetitive and unique fractions of female dna were denatured again and coupled via diazotization or cyanogen bromide to macroporous sephacryl s-500. enrichment of y-chromosomal sequences was achieved by cycling each of the different fractions of male dna under optimized hybridization conditions over a column with a m ... | 1986 | 3944419 |
| changes in the pattern of histone h1 phosphorylation during drosophila hydei embryogenesis. | histone h1 phosphorylation was examined during embryonic development of drosophila hydei. a changing pattern of h1 phosphorylation upon separation on an acid-urea polyacrylamide gel was observed in the course of drosophila embryogenesis. it is considered to be related to the decrease of the mitotic activity of the cells as development proceeds. | 1986 | 3807901 |
| locations of z-dna in polytene chromosomes. | in polytene chromosomes of drosophila hydei and d. melanogaster, z-dna was identified in varying distribution after different conditions for fixation were used. when salivary glands were fixed and squashed in 50% acetic acid alone, z-dna was found in the less dense dna regions, such as interbands, some puffs, and a few of the less dense bands. prefixation that combined ethanol and acetic acid exposure led to prominent immunofluorescent staining of the bands, generally but not strictly correlatin ... | 1985 | 3988806 |
| lampbrush chromosome loop-specificity of transcript morphology in spermatocyte nuclei of drosophila hydei. | the transcript morphology in the lampbrush chromosome loop pairs ;threads' and ;pseudonucleolus' of the y chromosome in primary spermatocytes of drosophila hydei has been investigated by the miller spreading technique. each loop pair carries giant transcripts with a secondary structure characteristic of the respective loop. the lengths of the transcribed regions are in the range 500-1500 kb or even larger. the results of our experiments are discussed in the context of loop ultrastructure, molecu ... | 1984 | 16453579 |
| computer map of salivary gland chromosomes in drosophila hydei. | | 1984 | 6548189 |
| lampbrush loop-specific protein of drosophila hydei. | by immunofluorescence techniques and protein blotting experiments we have shown that an antiserum specifically reacts with a mr 80,000 protein (the "ps protein") in the lampbrush loop " pseudonucleolus " in spermatocyte nuclei of drosophila hydei. comparative studies of x/y and x/0 testes indicate that the gene encoding the ps protein is not located on the y chromosome but on an autosome or the x chromosome. the ps protein is tissue specific. it is likely to be a rather conserved protein since t ... | 1984 | 6587357 |
| activation of potential initiation sites of dna replication and induction of new initiation within the same cycle by puromycin in drosophila polytene chromosomes. | dna replication in the polytene chromosomes of larval salivary glands of drosophila hydei has been examined under normal physiological conditions, with or without puromycin, by an autoradiographic procedure using [3h]thymidine. it has been demonstrated that puromycin induces new labelling patterns that can be identified as initiation patterns. such initiation patterns were found to have been induced during both the initial (interband labelling patterns) and the terminal (discontinuous) phases. b ... | 1984 | 6715430 |
| involvement of y chromosomal loci in the synthesis of drosophila hydei sperm proteins. | a comparative study of the protein patterns in testes of wild-type and x/o flies of drosophila hydei revealed quantitative differences in at least three major protein fractions. one protein component of a mr 155,000 fraction and a protein of mr 35,000 are completely absent in x/o testes. the amount of protein in a mr 55,000 fraction is considerably reduced. the tubulins, which are part of this fraction, are also reduced in amount. all three proteins were found as constituents of sperm tails. stu ... | 1983 | 6194026 |
| identification of the heat shock band 2-48b of drosophila hydei and determination of its haploid dna content. | the heat shock locus 2-48b situated at the tip of the second chromosome of drosophila hydei has been studied by various cytologic methods. both from puffing behaviour and in situ hybridization on both wildtype animals and heterozygotes for the mutant chromosome df(2)e20 the actual site is localized in band 2-48b8. electron microscopically this band appears to be a medium size, dotted band. from cytophotometric measurements on feulgen stained chromosomes and electron microscopic observations the ... | 1983 | 6617671 |
| y chromosomal dna of drosophila hydei. | six recombinant dna clones are described, which are derived from the y chromosome of drosophila hydei. they reveal characteristic features of y chromosomal dna sequences. three of the cloned inserts are y-specific and are members of the same family of repeated sequences associated with the lampbrush loop-forming fertility gene "nooses" in the short arm of the y chromosome. the other three cloned sequences are members of three different families of repeated sequences, but display a small amount o ... | 1983 | 6306254 |
| the banding pattern of the salivary gland chromosomes of drosophila hydei. | the banding pattern of the salivary gland chromosomes of d. hydei was investigated in the electron microscope. we compared the banding pattern of squashed chromosomes with non-squashed preparations and observed that the fixation and squash procedure we used does not introduce artificial changes in the banding pattern of the chromosome. an electron microscopic map was made of the banding pattern of the distal half of the second salivary gland chromosome. on the basis of the number of bands in thi ... | 1983 | 6406232 |
| the notch locus of drosophila hydei: alleles, phenotypes and functional organization. | the notch (n) locus of drosophila hydei and a series of its alleles and phenotypes are described. some models are discussed to explain the opposite effects of some alleles on the structure of the wing, the neomorphic action of n(ax) over typical n alleles and the interaction with the mutation costal-nick (cnk). | 1983 | 17246107 |
| molecular cloning of microdissected lampbrush loop dna sequences of drosophila hydei. | we microdissected a y chromosomal lampbrush loop pair from primary spermatocyte nuclei of drosophila hydei and cloned the dna directly at the microscale. four of the 12 recombinant dna clones recovered display in situ hybridization to mitotic metaphase y chromosomes, preferentially in the chromosomal region identified as the origin of the lampbrush loop pair. all clones, however, also hybridize to autosomal and x chromosomal loci in polytene chromosomes. y chromosomal dna sequences of d. hydei a ... | 1983 | 16453474 |
| determination of the region of rdna involved in polytenization in salivary glands of drosophila hydei. | during the formation of polytene chromosomes in salivary glands of drosophila hydei, the genes for ribosomal rna (rdna) are underreplicated relative to the rest of the genome. we have measured the number of rrna genes with and without intervening sequences (ivs+ and ivs- genes) in polytene chromosomes of different genotypes. in the group of genotypes having a large number of ivs- rrna genes polytenization only occurs within the cluster of ivs- genes. in each of these genotypes rdna polytenizatio ... | 1983 | 6577262 |
| dna clones and rna transcripts of four lampbrush loops from the y chromosome of drosophila hydei. | drosophila hydei clones representing transcribed middle-repetitive sequences from four of six major lampbrush loops of the y chromosome were isolated. sequences homologous to each clone are clustered in a particular locus on the y chromosome, but additional euchromatic sites were found for one of the transcribed clones. in situ hybridization to lampbrush-loops rna permitted the identification of clones homologous with the two "nooses" loops on ys and with the "clubs" and "tubular ribbons" on the ... | 1983 | 6186391 |
| identification of cloned y chromosomal dna sequences from a lampbrush loop of drosophila hydei. | by recombinant dna techniques, a y chromosomal sequence of drosophila hydei was isolated. this dna sequence of 8.93-kilobase length is a member of a family of repetitive sequences located in the short arm of the y chromosome. tissue-specific transcripts complementary to the cloned sequence were found in testes rna. in situ hybridization demonstrated that such transcripts are present in the lampbrush loop pair "nooses" in primary spermatocyte nuclei--a loop pair that is associated with the only f ... | 1982 | 6291024 |
| genetic fine structure of the y chromosome of drosophila hydei. | a genetic map of the y chromosome of drosophila hydei has been constructed from deletion/complementation experiments, with the aid of male sterile mutants of the y chromosome. a central conclusion of our experiments is that not more than a single complementation group can be detected in each of the lampbrush loop forming sites. additional complementation groups, functionally independent of lampbrush loops, reside between these loci. six complementation groups have been defined by several methods ... | 1982 | 7173604 |
| rna polymerase i from drosophila hydei pupae-purification and partial characterization. | | 1982 | 7106288 |
| the banding pattern of the segment 46a-48c in drosophila hydeï polytene chromosomes as studied by confocal scanning light microscopy (cslm). | | 1982 | 7075699 |
| recombination frequency and dna content of the distal part of the second chromosome of drosophila hydei sturtevant. | | 1982 | 7075726 |
| "hybrid" x--y translocation chromosomes of drosophila hydei and d. neohydei. | the y chromosome of drosophila carries fertility genes which, in part, develop lampbrush loops during the meiotic prophase. hybrid males from crosses between d. hydei and d. neohydei are fertile although the morphology of the lampbrush loops differs between both species. with the aid of x ray induced "hybrid" x-y translocation chromosomes the question has been studied whether y chromosomal genes of d. neohydei can substitute deletions in the y chromosome of d. hydei. although the induction of tr ... | 1982 | 6897381 |
| the effects of cytochalasin b and colchicine on the morphogenesis of mitochondria in drosophila hydei during meiosis and early spermiogenesis. an in vitro study. | morphogenesis of mitochondria in male germ cells in cultivated cytocysts begins in early prophase i at which time mitochondria thicken and become ordered along the spindle apparatus during meiosis. at the end of the second meiotic division they aggregate to form the nebenkern. in the presence of colchicine or cytochalasin b mitochondria are able to begin differentiation, although the correct course of meiosis is not guaranteed. in medium supplemented with colchicine they undergo normal thickenin ... | 1982 | 6807551 |
| chromosomal arrangement of heat shock locus 2-48b in drosophila hydei. | cdna, copied from nuclear rna isolated from heat shocked drosophila hydei cells, has been cloned. from this collection of clones a clone, n09-15, with a 450 bp insert has been isolated that hybridizes in situ to the heat shock locus-2-48b of drosophila hydei. the n09-15 sequence is present in two different genomic arrangements, as shown by restriction mapping, in our wild type d. hydei population. these genomic arrangements are allelic. both alleles contain multiple copies of the n09-15 sequence ... | 1982 | 6288330 |
| analytical studies of chromosomal transcription detected by an endogenous hybridization technique (eht) using autoradiography and indirect immunofluorescence in drosophila hydei. | | 1981 | 7041502 |
| ribosomal rna genes with an intervening sequence are clustered within the x chromosomal ribosomal dna of drosophila hydei. | | 1981 | 7310870 |
| bristle patterns, clones and cell competition along the anterior margin ofnotch wings ofdrosophila hydei. | the bristle pattern along the anterior margin ofnotch (n1-22.3) wings ofdrosophila hydei and the occurrence ofyellow (y 1-38.8) marked clones induced by x-ray irradiation during various larval stages are described. unirradiatedn/n + wings show gaps ('notches') in the longitudinal bristle rows along the 1st longitudinal vein, with tufts of bristles particularly near gaps. x-ray irradiation increases the number and total length of the gaps. the patterning of bristles along the margin depends on th ... | 1981 | 28305369 |
| analysis of nuclear proteins in primary spermatocytes of drosophila hydei: the correlation of nuclear proteins with the function of the y chromosomal loops. | the protein content of spermatocyte nuclei from x/y males and mutants of d. hydei which lack different y chromosomal loop forming sites, was compared with that of x/0 males in 14c/3h double labelling experiments. proteins of 45,000, 52,000, 54,000, 66,000, 80,000, 84,000 and 170,000 dalton are found to be enriched in nuclei containing two or more active y chromosomal loop forming sites. these proteins are also present in the nuclei of x0 males. in the complete absence of the y-chromosomal loops ... | 1981 | 7297252 |
| differential staining of y chromosomal lampbrush loops of drosophila hydei. | the lampbrush loops of the y chromosome in primary spermatocytes of drosophila hydei can be stained in a site specific manner employing a modified giemsa technique. in this communication it is shown that pronase pretreatment changes the staining properties of the various y loops as well as of the x and autosomes. in addition it is shown that the various chromosomal structures display differences in sensitivity against the action of the enzyme supporting the idea of a site specificity of rnp form ... | 1981 | 7297244 |
| in vitro spermatogenesis in drosophila. i. development of isolated spermatocyte cysts from wild-type d. hydei. | in vitro spermatogenesis of isolated single spermatocyte cysts of drosophila hydei was studied by microscopic observations and time-lapse cinematography. cysts of spermatocytes isolated during diplotene develop as far as the coiling stage of spermatid differentiation. the existence of an interphase between meiosis i and meiosis ii is, for the first time, documented. meiosis, nebenkern formation, and elongation of spermatids occur just as in d. melanogaster; however, an individualization cone, as ... | 1981 | 7296632 |
| pyridoxine induced puffing (ii-48 c) and synthesis of a 40 kd protein in drosophila hydei salivary glands. | | 1981 | 7261712 |
| localization of rna polymerase b and histones in the nucleus of primary spermatocytes of drosophila hydei, studied by immunofluorescence microscopy. | by means of indirect immunofluorescence microscopy, we have studied the distribution of rna polymerase b, of the nucleosomal histones h2b, h3, and h4 and of histone h1, in nuclei of primary spermatocytes of drosophila hydei. rna polymerase b and histones, including h1, are found to be present on the loop structures of the y chromosome. the nucleolus stains only for the histones, but not for rna polymerase b. various mutants deficient for some of the loops or altering their morphology, were used ... | 1981 | 7227044 |
| distribution of spacer length classes and the intervening sequence among different nucleolus organizers in drosophila hydei. | drosophila hydei rrna genes from different chromosomes and from different stocks have been studied by restriction enzyme analysis. in dna from wild-type females, about half of the x chromosomal rrna genes are interrupted by an intervening sequence within the 28s coding region. in contrast to d. melanogaster, the intervening sequences belong to a single size class of 6.0 kb. although there are two nucleolus organizers on the y chromosome, genes containing the intervening sequence seem to be restr ... | 1981 | 6268371 |
| cytological dissection of sex chromosome heterochromatin of drosophila hydei. | prophase chromosomes of drosophila hydei were stained with 0.5 microgram/ml hoechst 33258 and examined under a fluorescence microscope. while autosomal and x chromosome heterochromatin are homogeneously fluorescent, the entirely heterochromatic y chromosome exhibits an extremely fine longitudinal differentiation, being subdivided into 18 different regions defined by the degree of fluorescence and the presence of constrictions. thus high resolution hoechst banding of prophase chromosomes provides ... | 1981 | 6173175 |
| induction of tyrosine aminotransferase by pyridoxine in drosophila hydei. | salivary glands incubated in various concentrations of pyridoxine (vitamin b6) show increasing tyrosine aminotransferase (tat) activity at concentrations up to 10(-5) m and then decreasing activity up to 10(-2) m but in all cases the activity is greater than that of the controls. this increase in activity is demonstrable for up to 6 h, the longest period tested, and is dependent on the synthesis of new mrna. a similar increase in tat activity is observed in salivary glands subjected to heat shoc ... | 1981 | 6114816 |
| new cell line: established cell lines of drosophila hydei. | four cell lines have been isolated from drosophila hydei embryos. three lines have a normal xy karyotype, the fourth has an xo karyotype with an additional small heterochromatic fragment. the cells contain presumable cytoplasmic virus like particles. | 1980 | 7450782 |
| characterization of cloned ribosomal dna from drosophila hydei. | the structure of ribosomal genes from the fly drosophila hydei has been analyzed. ecori fragments, cloned in a plasmid vector, were mapped by restriction enzyme analysis. the lengths of the regions coding for 18s and 28s rrna were defined by r-loop formation. from these data a physical map of the rrna genes was constructed. there are two major types of rdna units in d. hydei, one having a size of 11 kb and the other a size of 17 kb. the 17 kb unit results from an intervening sequence (ivs) of 6. ... | 1980 | 6255425 |
| bristle patterns and clones along a compartment border in the anterior wing margin ofdrosophila hydei. | the bristle pattern along the first longitudinal vein of the wing ofd. hydei differs from that ofd. melanogaster. instead of a triple row,d. hydei and some allied species show a pattern of five parallel bristle rows of which the medial row (mr) is comparable to the medial triple row (mtr) ofd. melanogaster. cells of the mr can be made homozygousyellow (y) by induction of mitotic recombination in heterozygousy/y + females. until 70 h after egg laying (ael), the mr clones ind. hydei overlap with o ... | 1980 | 28305756 |
| rna polymerase iii from drosophila hydei pupae. purification and partial characterization. | dna-dependent rna polymerase iii, which is usually highly resistant to alpha-amanitin, has been purified from drosophila hydei pupae. the enzyme is insensitive to alpha-amanitin concentrations up to 0.1 microm; at 100 microm alpha-amanitin the enzyme activity is inhibited by approximately 10%. the enzyme was extracted at low ionic strength and purified to homogeneity by six purification steps; 0.1--0.2 mg enzyme/kg pupae could be obtained. the subunit composition of the enzyme was determined aft ... | 1980 | 7460903 |
| molecular dimorphism of the x chromosome of male and female larvae in drosophila hydei. | | 1980 | 6174006 |
| development capacities of mixed normal and neoplastic l(3)gl imaginal discs and neuroblast tissue in drosophila hydei. | the pleiotropic mutant lethal(3)giant larvae [l(3)gl] of drosophila hydei exhibits among other anatomical defects, hypertrophy of the larval brain and imaginal discs. both hypertrophic tissues when transplanted into wild-type female flies behave as fast growing and lethal neoplasms. implanted into mature wild-type larvae they fail to metamorphose. when l(3)gl neoplastic brain tissue or imaginal discs were mixed with normal imaginal discs, cultured in vivo in the abdomen of adult females and tran ... | 1980 | 7450328 |
| disproportionate rdna replication does occur in diploid tissue in drosophila hydei. | the rdna content in drosophila hydei has been compared in wild-type and in two translocation genotypes possessing only one nucleolus organizer. in highly polyploid salivary glands where rdna is underreplicated, an 'independent polytenization' of the rdna occurs resulting in about the same rdna level in each genotype independently of the number of nucleolous organizers present in the genome. thus, the situation in the salivary glands of d. hydei is similar to that in d. melanogaster (spear and ga ... | 1980 | 6934366 |
| lengths of transcribed rdna repeating units in spermatocytes of drosophila hydei: only genes without an intervening sequence are expressed. | in drosophila hydei a 5 kb long intervening sequence (ivs) which is limited to only one of the three nucleolus organizers occurs in the 28s coding region of the rdna (kunz and glätzer, 1979). this raises the possibility to study transcription of repeated genes with long intervening sequences. three genotypes of males were studied each having only one defined nucleolus organizer. spermatocytes of single males were spread in a solution of low salt and examined by electron microscopy. the length di ... | 1979 | 533667 |
| a procedure for the cloning and identification of y-specific middle repetitive sequences in drosophila hydei. | | 1979 | 537053 |
| the parthenogenetic capacities and genetic structures of sympatric populations of drosophila mercatorum and drosophila hydei. | drosophila mercatorum is a sexual species that can reproduce parthenogenetically in the laboratory. a previous study showed that a natural population of d. mercatorum inhabiting the kamuela garbage dump on the island of hawaii could produce both viable parthenogenetic adults and self-sustaining parthenogenetic lines. the present study deals with a second screen for parthenogenesis and an isozyme survey performed on natural populations of d. mercatorum and d. hydei caught in patches of opuntia tu ... | 1979 | 17248952 |
| the activity of two heat shock loci of drosophila hydei in tissue culture cells and salivary gland cells as analyzed by in situ hybridization of complementary dna. | complementary dna was made to poly a+ nuclear or polysomal rna isolated from heat shock tissue culture cells of drosophila hydei. a number of loci other than the four major heat shock loci are labelled after in situ hybridization of these cdna preparations, while solution hybridization indicated that only about 10% of the cdna was specific for heat shocked cells. removal of the fraction of cdna which could react with 25 degrees c rna and subsequent in situ hybridization of heat shock specific cd ... | 1979 | 467169 |
| heat-shock peptides in drosophila hydei and their synthesis in vitro. | | 1978 | 689021 |
| indirect immunofluorescence microscopy of microtubular structures in male germ cells of wildtype and l(3)pl (lethal-polyploid) drosophila hydei. | tubulin-containing structures of the male germ cells of drosophila hydei crossreact in indirect immunofluorescence microscopy with antibody directed against homogeneous porcine brain tubulin. there is no detectable difference in reactivity between germ cells of wildtype flies and the mutant l(3)pl (lethal-polyploid) which is characterized by microtubular abnormalities. however, the technique of indirect immunofluorescence microscopy allows the direct visualization of several abnormalities in the ... | 1978 | 350682 |
| the products of the "heat-shock" loci of drosophila hydei. correlation between locus 2-36a and the 70,000 mw "heat-shock" peptide. | antibody was raised against total drosophila hydei embryonic cellular protein with a molecular weight between 65,000 and 70,000 dalton. this antiserum reacted with the 70,000 mw "heat-shock" peptide found in "s labelled cell extracts of "heat-shocked" d. hydei tissue culture cells or salivary glands.--the antibody was coupled to sepharose 4b and this material was used to absorb polysomes obtained from tissue culture cells incubated at 37 degrees c in the presence of tritiated rna precursors. the ... | 1978 | 639626 |