| the intron boundaries and flanking rrna coding sequences of calliphora erythrocephala rdna. | we have sequenced the available cloned examples of the intron-coding sequence junctions for the rdna of the higher dipteran, calliphora erythrocephala. the introns interrupt the rdna at the same position as the type 1 intron family detected in drosophila melanogaster and d. virilis (10,11). a duplication of 14 base pairs of the 28s rrna coding sequence surrounds a short version of the major genomic length class of introns. this same duplication is associated with boundaries of the type 1 introns ... | 1984 | 6322117 |
| identification, molecular cloning, and mutagenesis of saccharomyces cerevisiae rna polymerase genes. | three different regions of saccharomyces cerevisiae dna were identified by using as hybridization probe a fragment of drosophila melanogaster dna that encodes an rna polymerase ii (ec 2.7.7.6) polypeptide. two of these regions have been molecularly cloned. each contains a sequence related not only to the d. melanogaster dna fragment that was used as a probe in its isolation but also to the immediately adjacent dna fragment of the d. melanogaster rna polymerase ii gene. the two cloned s. cerevisi ... | 1984 | 6326108 |
| transcription of the mouse ribosomal spacer region. | this paper describes experiments designed to test the hypothesis that dna sequences upstream from the mouse rrna promoter are transcribed in vivo or in vitro. plasmid pb28 contains a sali restriction fragment that extends from -169 to -1,894 base pairs, with respect to the origin of transcription of pre-rrna. labeled rna synthesized in intact cells does not hybridize to this region. neither s1 nuclease mapping nor rna dot blot hybridization revealed the presence of sequences complementary to thi ... | 1984 | 6328269 |
| drosophila melanogaster has only one myosin alkali light-chain gene which encodes a protein with considerable amino acid sequence homology to chicken myosin alkali light chains. | a chimeric lambda dna molecule containing the myosin alkali light-chain gene of drosophila melanogaster was isolated. the encoded amino acid sequence was determined from the nucleic acid sequence of a cdna homologous to the genomic clone. the identity of the encoded protein was established by two criteria: (i) sequence homology with the chicken alkali light-chain proteins and (ii) comparison of the two-dimensional gel electrophoretic pattern of the peptides synthesized by in vitro translation of ... | 1984 | 6328279 |
| regulation of drosophila alpha- and beta-tubulin genes during development. | both the alpha and the beta subunit of tubulin in drosophila melanogaster are encoded by small multigene families. using heterologous hybridization probes representing chicken alpha- and beta-tubulin genes, four complementary alpha- and four beta-tubulin gene sequences from drosophila have been isolated. each gene has been individually mapped cytogenically by in situ hybridization of nucleic acid probes to polytene chromosomes. it is clear that the genes in each family are dispersed rather than ... | 1984 | 6329853 |
| mutagenic activity of selected aromatic amines and polycyclic hydrocarbons in drosophila melanogaster. | with the use of a series of wild-type and repair-deficient strains and appropriate application procedures, it is possible to demonstrate that carcinogenic aromatic amines and polycyclic hydrocarbons are mutagens in drosophila. we have shown evidence that aaf, n-oh-aaf, aco-aaf, bp, das and dmba produce recessive lethals when fed to or injected into adult males. mutagenic activity was also observed when male larvae were exposed to aaf, bp, dmba, 3-mc or na. da was not mutagenic in the recessive l ... | 1983 | 6402690 |
| evaluation of the mutagenic potential of the hair dye n-methyl-amino-2-nitro-4-n',n'-bis-(2-hydroxyethyl)-aminobenzene in a battery consisting of drosophila and mammalian cytogenetic assays. | the compound n-methyl-amino-2-nitro-4-n', n'-bis(2-hydroxyethyl)-aminobenzene was tested for mutagenic activity in the sex-linked recessive lethal test with drosophila melanogaster, the induction of chromosomal aberrations and sister-chromatid exchanges (sces) with chinese hamster ovary (cho) cells in vitro, and the micronucleus test with mouse bone-marrow cells in vivo. consistently negative results were obtained with the 3 tests. the sce tests gave positive results with prolonged treatments. i ... | 1983 | 6402694 |
| evaluation of mutagenic effect of the fungicide fenaminosulf in drosophila melanogaster. | fenaminosulf (p-dimethylaminobenzenediazo sodium sulfonate, cas registry no. 140-56-7) which is an active ingredient in several commercial fungicides was reported to be mutagenic in salmonella typhimurium (mccann et al., 1975), bacillus subtilis (kada et al., 1974) and shown to cause chromosome aberrations in plants (zutshi and kaul, 1975). since fenaminosulf has structural similarity to the potent carcinogen, butter yellow (p-dimethylaminoazobenzene, cas registry no. 60-11-7), the present studi ... | 1983 | 6402695 |
| conformation of oligonucleotides and nucleic acids modified with 2-aminofluorene or 2-acetylaminofluorene. | the first part of this work deals with the thermal stability of oligonucleotides modified with acetylaminofluorene and aminofluorene, respectively. the complementary oligonucleotides d(cgcg), d(cgtacg) and d(aattgcaatt) have been studied by ultraviolet absorption and circular dichroism. in high salt concentration and at low temperature, the three oligonucleotides form double-stranded helices which have the b-form substitution of guanine residues in these oligonucleotides by acetylated or deacety ... | 1983 | 6403346 |
| interactive effects of temperature and geography on emigration behavior of drosophila melanogaster: climatic and island factors. | | 1983 | 6404243 |
| geographic variation in g6pd and pgd allele frequencies in drosophila melanogaster. | | 1983 | 6404856 |
| three loci related to the src oncogene and tyrosine-specific protein kinase activity in drosophila. | rous sarcoma virus (rsv) is an acutely oncogenic avian retrovirus which induces sarcomas in animals and transforms fibroblasts in cell culture. genetic analysis indicates that the viral src gene (v-src) mediates neoplastic transformation. the product of v-src is a 60,000 molecular weight (mw) phosphoprotein (pp60v-src) possessing the enzymatic activity of a tyrosine-specific protein kinase. the viral src gene is derived from a cellular gene (c-src) which also encodes a 60,000 mw phosphoprotein ( ... | 1983 | 6405280 |
| enzymes involved in oxygen detoxification during development of drosophila melanogaster. | activities of superoxide dismutase (sod), catalase (cat), and peroxidases (per) were examined at 24-h intervals during drosophila development. sod activities show a u-shaped curve from egg to adult stages whereas cat and per are consistently low in egg through larval stages. male and female larvae have similar activities of sod, cat, and per whereas male adults have elevated activities of these enzymes. larvae are more sensitive to h2o2 and 3-amino-1,2,4-triazole (an inhibitor of cat) than adult ... | 1983 | 6406261 |
| genetic toxicology of ethylenediaminetetraacetic acid (edta). | edta and its salts have a number of applications in medicine and pharmacy. edta is used to remove calcium from the human body, and serves as an anticoagulant and as a detoxicant after poisoning by heavy metals. it is often used in analytical chemistry for complexometric titrations and many other purposes. because the compound is of rather low toxicity, it is used as a food additive to bind metal ions. edta affects the inhibition of dna synthesis in primary cultures of mammalian cells. this may b ... | 1983 | 6406880 |
| evaluation of propylene oxide for mutagenic activity in 3 in vivo test systems. | propylene oxide (cas no. 75-56-9) was tested for mutagenic activity following vapor exposure using 3 in vivo test systems. rat dominant lethal and mouse sperm-head morphology assays were conducted using males exposed to propylene oxide at 300 ppm in a dynamic exposure chamber for 7 h per day on 5 consecutive days. a sex-linked recessive lethal test in drosophila melanogaster employed a 24-h static exposure to propylene oxide at 645 ppm. male mice were killed 1, 3, 5, 7, and 9 weeks post-exposure ... | 1983 | 6406882 |
| identification of a structural gene for a rna polymerase ii polypeptide in drosophila melanogaster and mammalian species. | using subclones representing 14 kilobase pairs (kb) of dna from the drosophila melanogaster rna polymerase ii (ec 2.7.7.6) x-linked genetic locus, rpii, we have identified four poly(a)+ rna transcripts in adult flies. the dna encoding only one of these, a 7-kb transcript, cross-hybridized to mammalian dna. dna from alpha-amanitin-resistant (amar) chinese hamster ovary (cho) and human cells was used to transform the temperature-sensitive (ts) rna polymerase ii syrian hamster mutant tsaf8. the acq ... | 1983 | 6407013 |
| high proportion of multi-locus deletions among hycanthone-induced x-linked recessive lethals in drosophila melanogaster. | 328 x-linked recessive lethal mutations induced in late spermatids by hycanthone methanesulfonate were tested for coverage by duplications that comprised, in total, about 24% of the euchromatic x chromosome; 78 lethals appeared to be covered. crossover localization tests of a random sample of 38 non-covered lethals revealed 4 chromosomes carrying a lethal within a duplicated segment. lethals localized to a particular region were crossed to reference deficiencies and single-locus mutations, and i ... | 1983 | 6408464 |
| drosophila melanogaster mitochondrial dna, a novel organization and genetic code. | the sequence of a 4,869 base-pair fragment of drosophila melanogaster mitochondrial dna is presented. it contains genes for cytochrome oxidase subunits i, ii and iii, atpase subunit 6 and six trnas together with two unassigned reading frames. the gene organization differs from that of mammalian mitochondrial dnas. evidence is provided for a genetic code in which aga codes for serine and the quadruplet ataa is used in initiation of translation. | 1983 | 6408489 |
| [induction by mycotoxins of somatic mosaicism in drosophila and dna repair in mammalian liver cell cultures]. | the genotoxic activity of four mycotoxins has been studied. high level of somatic mutagenesis in imaginal discs of drosophila melanogaster larvae and dna repair synthesis in human embryo and adult rat liver cell cultures were inducible only by highly carcinogenic aflatoxin b1. patulin, a weak direct-action carcinogenic substance, slightly elevated the mutagenesis in somatic cells of drosophila but did not induce dna repair synthesis in liver cell cultures. citrinin that did not exhibit any carci ... | 1983 | 6409185 |
| the genetic toxicology of kathon biocide, a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one. | kathon biocide, an aqueous solution containing a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one in an approximate ratio of 3:1, was tested for mutagenic activity in salmonella typhimurium, l5178y mouse lymphoma cells in culture and drosophila melanogaster. tests also were conducted for chromosome aberrations in vivo on mouse bone marrow cells, for dna damage/repair in primary rat hepatocytes in culture, and for morphological transformation in c3h 10t1/2 cells ... | 1983 | 6410231 |
| the versatility of drosophila melanogaster for mutagenicity testing. | i trust that i have accomplished my aim in this presentation, to demonstrate that drosophila mutagenesis testing protocols are varied and are adaptable. the choices are many, at different levels. first, the route of administration can be chosen that is most appropriate for the chemical compound or to duplicate the human exposure route or to obtain data needed for some particular purpose, such as comparative mutagenesis. second, the genetic test scheme or combination of schemes can be chosen to s ... | 1983 | 6410959 |
| telomere regions in drosophila share complex dna sequences with pericentric heterochromatin. | a 12 kb fragment of drosophila melanogaster dna cloned in a lambda phage, lambda t-a, is shown by in situ hybridization to contain sequences homologous to dna at the extreme ends of each of the polytene chromosomes and to the pericentric sequences present in the beta heterochromatin. this pattern of hybridization is seen for each of the four d. melanogaster stocks that have been studied. most of the sequence in lambda t-a shows no detectable homology to dna within the banded chromosome arms. (th ... | 1983 | 6411353 |
| nh2-terminal processing of drosophila melanogaster actin. sequential removal of two amino acids. | class ii actins, such as drosophila and mammalian skeletal muscle actins, have genes that code for a met-x-asp nh2 terminus where x is usually cysteine. these actins have an ac-asp nh2 terminus so two amino acids must be removed. to determine the nature of this processing, we labeled drosophila schneider l-2 cells with [35s]methionine or cysteine, isolated the actin, and analyzed the nh2-terminal actin tryptic peptides and their thermolysin digestion products. after a 4-h labeling period, we det ... | 1983 | 6411730 |
| mouse and drosophila genes encoding the major heat shock protein (hsp70) are highly conserved. | we used a cloned drosophila melanogaster hsp70 gene to hybrid-select heat shock-induced mouse mrna and showed that this mrna encodes the major mouse heat shock protein. this result suggests that the sequence of the hsp70 gene(s) is highly conserved. | 1983 | 6413838 |
| the sex-linked recessive lethal test for mutagenesis in drosophila melanogaster. a report of the u.s. environmental protection agency gene-tox program. | the test for sex-linked recessive lethals (slrl) in drosophila melanogaster has been used to detect induced mutations since 1927. the advantage of the test for both screening and hazard evaluation is its objectivity in testing for transmissible mutations in the germ cells of a eukaryote. statistical criteria for both positive and negative mutagenicity at the highest concentration tested under a particular exposure condition were developed by the work group, and a recommended protocol for future ... | 1983 | 6413857 |
| analysis of the chromatin assembled in germinal vesicles of xenopus oocytes. | we have injected circular dna, labeled with 32p at a single restriction site, into germinal vesicles of xenopus laevis oocytes in order to study the nucleosome arrangement on the assembled minichromosomes. two types of genes were used in these studies, the somatic 5 s rna gene unit of xenopus borealis and the histone gene unit of drosophila melanogaster. we find that injections of labeled dna alone, at 1 ng dna per oocyte, results in irregularly spaced nucleosomes and partially supercoiled dna m ... | 1983 | 6415291 |
| genetic toxicity of dopamine. | the genetic toxicity of dopamine was studied in a battery of test systems including dna single-strand break analysis in cultured human skin fibroblasts, the salmonella/mammalian-microsome mutagenicity test, sister-chromatid exchange analysis in human lymphocytes, the mouse-lymphoma forward mutation assay, the sex-linked recessive lethal test in drosophila melanogaster and the micronucleus test in mouse and rat. dopamine at concentrations of 50-300 micrograms/ml induced dna strand breaks in human ... | 1983 | 6415476 |
| mutagenicity of rubber additives and curing fumes. results from five short-term bioassays. | the mutagenicity of rubber additives and curing fumes from some rubber formulations were studied in five short-term tests: point mutations in chinese hamster v79 cells, the induction of sister chromatid exchanges in chinese hamster ovary cells, micronuclei in erythrocytes of chinese hamster bone marrow, sex-linked recessive lethal mutations in drosophila melanogaster, and reverse mutations in the salmonella/microsome assay. when 46 rubber additives were tested with salmonella, 15 compounds were ... | 1983 | 6415811 |
| aberrant splicing of drosophila alcohol dehydrogenase transcripts in saccharomyces cerevisiae. | we have investigated the ability of transcripts of the drosophila melanogaster alcohol dehydrogenase gene to be spliced in saccharomyces cerevisiae. the alcohol dehydrogenase gene was cloned in s. cerevisiae on a 2 micron dna-based vector and a hybrid yeast actin-drosophila alcohol dehydrogenase gene was constructed to demonstrate that transcripts encoded on a 2 micron plasmid could be accurately and efficiently spliced. transcription of the drosophila gene occurred in yeast with and without a y ... | 1983 | 6416830 |
| a modified enzymatic-isotopic microassay for serotonin (5ht) using 5ht-n-acetyltransferase partially purified from drosophila. | serotonin-n-acetyltransferase (ec 2.3.1.5), partially purified from drosophila melanogaster (dnat) was substituted for rat liver enzyme (rnat) in a previously published radioenzymatic assay for serotonin (5ht). the purpose was to determine if this modification would increase the sensitivity and reliability of the original assay. compared with rnat, dnat is 3-4 times more active; it lacks secondary 5htp decarboxylase activity; and it is more stable. under conditions of the modified assay, the onl ... | 1983 | 6417427 |
| transient expression of genes introduced into cultured cells of drosophila. | recombinant plasmids in which the sequence encoding the bacterial chloramphenicol acetyltransferase (cat; acetyl-coa:chloramphenicol 3-o-acetyltransferase, ec 2.3.1.28) has been placed under the control of drosophila heat shock protein 70 (hsp 70) or copia promoters have been introduced into cultured cells of two drosophila species (schneider ii line of drosophila melanogaster and d. immigrans) as calcium-phosphate complexes. within 1-2 days after transfection functional cat enzyme was detected ... | 1983 | 6417663 |
| dephosphorylation of s6 and expression of the heat shock response in drosophila melanogaster. | a basic ribosomal phosphoprotein of 30,000 molecular weight was rapidly dephosphorylated in cultured drosophila melanogaster cells heat shocked at 37 degrees c. the protein was associated with the 40s ribosomal subunit and had an electrophoretic mobility similar to that of purified rat liver protein s6 on basic two-dimensional polyacrylamide gels as well as a similar partial proteolysis peptide map. in logarithmically growing cultures, this d. melanogaster s6 protein appeared to have a single ph ... | 1983 | 6419058 |
| study of artificial flavouring substances for mutagenicity in the salmonella/microsome, basc and micronucleus tests. | seventy-six compounds used as artificial flavouring substances in food products were studied for mutagenic properties by the use of the salmonella/mammalian microsome test (ames test), basc test on drosophila melanogaster and micronucleus test on mouse bone marrow. the following four compounds were mutagenic in ames tests: ethyl nitrite, ethyl 3-phenylglycidate, 6-methylquinoline and musk ambrette. of these, ethyl nitrite and musk ambrette also induced a significant (p less than or equal to 0.01 ... | 1983 | 6420251 |
| the genetical response to natural selection by varied environments. ii. observations on replicate populations in spatially varied laboratory environments. | from each of two populations of drosophila melanogaster, collected two months previously, from chateau tahbilk, s. australia and groningen, the netherlands, duplicate populations were initiated in each of four environments which differed in their degree of environmental heterogeneity. differing combinations of three food media based on oatmeal/treacle, potato or fig were used to simulate levels of environmental heterogeneity within the populations. the polymorphic loci, adh, est-6, g-6pdh, alpha ... | 1983 | 6421776 |
| saccharomyces cerevisiae synthesizes proteins related to the p21 gene product of ras genes found in mammals. | a family of normal vertebrate genes and oncogenes has been called the ras gene family. the name ras was assigned to this gene family based on the species of origin of the viral oncogenes of the rat-derived harvey and kirsten murine sarcoma viruses. there are now three known functional members of the ras gene family, and genes homologous to ras genes have been detected in the dna of a wide variety of mammals and in drosophila melanogaster. prior experiments have detected proteins coded for by ras ... | 1984 | 6422257 |
| metabolic activation of selected aromatic amines and polycyclic hydrocarbons by isolated subcellular fractions of drosophila melanogaster. | the applicability of microsomal preparations from drosophila melanogaster as the metabolic factor in the salmonella mutagenicity assay with strains ta98 and ta100 was evaluated. isolated cellular fractions (s27) from pb-pretreated flies activated n-acetyl-2-aminofluorene (2-aaf), n-hydroxy-n-acetyl-2-aminofluorene (n-oh-aaf), benzo[a]pyrene (bp), 9,10-dimethylanthracene (da) and 2-naphthylamine (na) into mutagenic metabolites. 7,-12-dimethylbenz[a]anthracene (dmba) was ineffective under the cond ... | 1984 | 6422283 |
| mutagenic activity of the pyrrolizidine alkaloids seneciphylline and senkirkine in drosophila and their transfer into rat milk. | seneciphylline and senkirkine, two pyrrolizidine alkaloids that occur in animal feeds and medicinal herbs, respectively, have been tested for their ability to produce sex-linked recessive lethals in males of drosophila melanogaster using the basc test (3-day feeding method). seneciphylline was found to be mutagenic at concentrations of 10(-5), 10(-4) and 10(-3)m, which produced 3.8% sex-linked recessive lethals (983 chromosomes tested). 9.0% (708) and 15.3% (327), respectively. senkirkine (10(-5 ... | 1984 | 6423472 |
| monoclonal antibody cross-reactions between drosophila and human brain. | a panel of 146 monoclonal antibodies (mabs), obtained with drosophila melanogaster tissue as primary immunogen, was tested for cross-reactivity with the human central nervous system. sites examined included spinal cord, cerebellum, hippocampus, and optic nerve. nonnervous tissues tested were liver and lymph node. approximately half of the antibodies reacted with one or more sites in the human central nervous system, identifying regional, cell class, and subcellular antigens. some recognized neur ... | 1983 | 6424113 |
| insect cell cultures in the study of attachment and pathogenicity of spiroplasmas and mycoplasmas. | the insect cell lines dm-1 (drosophila melanogaster), as-2 (aceratagallia sanguinolenta) and ac-20 (agallia constricta) were infected with spiroplasmas, mycoplasmas and acholeplasma laidlawii. in dm-1 cultures maintained at 25 degrees c in m1a medium, all strains multiplied except m. hyorhinis and the uncultivable sex-ratio organism. spiroplasma citri r8a2, s. floricola bnr-1 and obmg, s. apis pps-1 and the strains bc-3, corn stunt spiroplasma (css) and 277f produced cytopathogenic effects (cpe) ... | 1984 | 6424527 |
| ecdysteroids during the third larval instar in 1(3)ecd-1ts, a temperature-sensitive mutant of drosophila melanogaster. | the temperature-sensitive 1(3)ecd-1ts mutation (a. garen, l. kauvar, and j.a. lepesant (1977). proc. natl. acad. sci usa 74, 5099-5103.) has been used in several laboratories to obtain drosophila larvae deprived of moulting hormone. the development of mutants and controls during the third larval instar at permissive (20 degrees c) and restrictive temperatures (29 degrees c) was compared. pupariation was inhibited when larvae were shifted to the restrictive temperature immediately at the second m ... | 1984 | 6427061 |
| sequences isolated from a drosophila early-ecdysone puff are expressed in rat liver. | we have studied the presence of a cloned fragment of dna from drosophila melanogaster in other organisms by means of nucleic acid hybridization analysis. the isolated region is localized in polytene chromosomes at the 63f subdivision. this region includes a puff that responds within minutes to ecdysone stimulation. we have found that 63f dna from d. melanogaster hybridizes 'in situ' to both dna and rna from d. simulans, d. teissieri, and d. hydei. in all these species the isolated dna remains as ... | 1984 | 6428485 |
| fly and frog homoeo domains show homologies with yeast mating type regulatory proteins. | homoeotic genes in the bithorax and antennapedia complexes of drosophila melanogaster appear to specify the developmental fate of segments of the fly. some of these genes (ultrabithorax, antennapedia and fushi tarazu) share homology due to their conservation of a 'homoeo domain'1,2 consisting of 60 amino acids. cross-hybridization and cloning experiments show that the homoeo domain is conserved in a frog (xenopus laevis) gene expressed in early development and may also be present in earthworm, b ... | 1984 | 6429549 |
| isolation and characterization of nuclear hnrnp complexes from drosophila melanogaster tissue culture cells. | fractionation on sucrose gradients of nuclear described extracts prepared from cultured drosophila melanogaster cells by sonication of the nuclei in the presence of rat liver cytosol rnaase inhibitor revealed a complex polysome-like pattern of nuclear ribonucleoprotein complexes. the bulk of these heterogeneous ribonucleoprotein (hnrnp) complexes sedimented in the 30s to 80s zone of the sucrose gradient. according to biochemical and morphological data, the monomer particle proved to be the 45s h ... | 1983 | 6430014 |
| organization and mapping of a sequence on the drosophila melanogaster x and y chromosomes that is transcribed during spermatogenesis. | the d. melanogaster dna segment in the recombinant phage lambda dm2l1 contains at least eight copies of a tandemly repeated 1250-base pair (bp) sequence (henceforth called the 2l1 sequence). testes from xo d. melanogaster males contain an abundant 800-base rna species that is homologous to a 520-bp region of the 2l1 sequence. blotting experiments show that the 2l1 sequence is repeated in the d. melanogaster genome and is present on both the x and y chromosomes. with the use of x-y translocations ... | 1984 | 6430749 |
| chromosome mutation tests for mutagenesis in drosophila melanogaster. a report of the u.s. environmental protection agency gene-tox program. | the term 'chromosome mutations' was chosen and defined for this review to refer to alterations of chromosome structure (reciprocal, heritable translocations), of chromosome number (loss or gain of a whole chromosome), or of chromosome content (loss or gain of a part of a chromosome). chromosome mutations may result from chromosome breakage (clastogenesis) and its consequences or from disruption of chromosome behavior during cell division (nondisjunction). state-of-the-art protocols are outlined ... | 1984 | 6431279 |
| preadult lethality in four populations of drosophila melanogaster treated with formaldehyde. | samples from 4 populations of d. melanogaster were treated with formaldehyde by the larval feeding method, and induced lethality was scored. the results showed relevant differences among the populations analyzed. | 1984 | 6432574 |
| gene expression during drosophila melanogaster oogenesis: analysis by in situ hybridization to tissue sections. | the pattern of gene expression for specific genes during oogenesis has been examined by in situ hybridization to rna in sectioned ovarian preparations. the accumulation (1) of rna complementary to heat-shock genes, both before and after heat shock; (2) of rna complementary to three lambda phage recombinants which contain sequences expressed during oogenesis; and (3) of rna complementary to the rudimentary gene have been analyzed. gene expression in the ovaries is found to be dependent on both th ... | 1984 | 6432608 |
| selective destruction of a host blood cell type by a parasitoid wasp. | foreign objects that enter the hemocoel of drosophila melanogaster larvae are encapsulated by one type of blood cell, the lamellocyte, yet eggs of the parasitoid wasp leptopilina heterotoma remain unencapsulated in d. melanogaster larval hosts that have many lamellocytes. here we demonstrate that shortly after a female wasp oviposits in the hemocoel the lamellocytes undergo morphological changes and lose their adhesiveness. these affected blood cells are eventually destroyed as the parasitoid eg ... | 1984 | 6435126 |
| drosophila camp-dependent protein kinase. | camp-dependent protein kinase has been purified to homogeneity from adult bodies of drosophila melanogaster. it is tetrameric in structure with two regulatory and two catalytic subunits that dissociate when activated by camp. the regulatory subunit exists in phospho and dephospho forms, which have electrophoretic mobilities in sodium dodecyl sulfate-polyacrylamide gels corresponding to mr = 58,000 and 52,000, respectively. the catalytic subunit has a molecular weight of 40,000. the holoenzyme ha ... | 1984 | 6436241 |
| differential regulation of the 70k heat shock gene and related genes in saccharomyces cerevisiae. | saccharomyces cerevisiae contains a family of genes related to hsp70, the major heat shock gene of drosophila melanogaster. the transcription of three of these genes, which show no conservation of sequences 5' to the protein-coding region, was analyzed. the 5' flanking regions from the three genes were fused to the escherichia coli beta-galactosidase structural gene and introduced into yeasts on multicopy plasmids, putting the beta-galactosidase production under yeast promoter control. analysis ... | 1984 | 6436685 |
| sequences responsible for transcription termination on a gene segment in saccharomyces cerevisiae. | we have mapped a signal sequence for mrna 3'-end formation in saccharomyces cerevisiae by using a drosophila melanogaster dna segment that complements a yeast adenine-8 mutation. that the 3' end of the transcript in s. cerevisiae nearly coincides with that in d. melanogaster is consistent with the possibility that mrna termini are similarly determined in both organisms. deletion analysis reveals that the complete signal is no more than 21 base pairs long. part of the signal is the sequence ttttt ... | 1984 | 6436686 |
| high-resolution mapping of dnase i-hypersensitive sites of drosophila heat shock genes in drosophila melanogaster and saccharomyces cerevisiae. | high-resolution analysis of the chromatin structure of the promoter regions of five drosophila heat shock genes showed a similar location for the hypersensitive sequences relative to the start of transcription. for each of the five genes examined--those coding for hsp27, hsp26, hsp23, hsp70, and hsp83--the dnase i-hypersensitive sites in drosophila melanogaster nuclei mapped to two regions upstream of the coding region. these sites occurred on the average, 115 and 17 base pairs upstream from the ... | 1984 | 6436689 |
| structural homology between drosophila melanogaster and escherichia coli acidic ribosomal proteins. | antibodies raised against drosophila melanogaster ribosomal proteins (r-proteins) were used to examine possible structural relationships between eukaryotic and prokaryotic r-proteins. the antisera were raised against either groups of r-proteins or individually purified r-proteins. two antisera showed a cross-reaction with total escherichia coli r-proteins in ouchterlony double immunodiffusion assays: an antiserum against the d. melanogaster small subunit protein s14 (anti-s14) and an antiserum a ... | 1984 | 6437387 |
| expression of heat shock-beta-galactosidase hybrid genes in cultured drosophila cells. | derivatives of drosophila 70,000 dalton heat shock protein (hsp70) genes were constructed in which all of the hsp70 coding sequence but for the first seven codons had been substituted by a dna segment coding for e. coli beta-galactosidase. the constructs were capable of directing the synthesis of active beta-galactosidase in cos1 (sv40 transformed african green monkey kidney) cells. the hybrid genes were then used to develop a procedure permitting the introduction of genes and their transient ex ... | 1984 | 6441101 |
| learning in three species of diptera: the blow fly phormia regina, the fruit fly drosophila melanogaster, and the house fly musca domestica. | | 1984 | 6441564 |
| eukaryotic dna segments capable of autonomous replication in yeast. | a selective scheme is presented for isolating sequences capable of replicating autonomously in the yeast saccharomyces cerevisiae. yip5, a vector that contains the yeast gene ura3, does not transform a ura3 deletion mutant to ura+. hybrid yip5-escherichia coli dna molecules also fail to produce transformants. however, collections of molecular hybrids between yip5 and dna from any of six eukaryotes tested (s. cerevisiae, neurospora crassa, dictyostelium discoideum ceanhorabditis elegans, drosophi ... | 1980 | 6449009 |
| different chromatin states of the intron- and type 1 intron+ rrna genes of calliphora erythrocephala. | in most species of dipteran fly examined, a fraction of the rdna cistrons are interrupted by introns. these dipteran intron+ rrna genes are unique in that they are transcriptionally inactive. previous studies have investigated the mechanism underlying this transcriptional repression for rrna genes carrying the best characterized sequence family of such introns, the so-called type 1 introns first identified in drosophila melanogaster. these studies have established that cloned examples of both in ... | 1984 | 6510114 |
| altered expression of heat shock proteins in embryonal carcinoma and mouse early embryonic cells. | in a previous paper, we have shown that in the absence of stress, mouse embryonal carcinoma cells, like mouse early embryo multipotent cells, synthesize high levels of 89- and 70-kilodalton heat shock proteins (hsp)(o. bensaude and m. morange, embo j. 2:173-177, 1983). we report here the pattern of proteins synthesized after a short period of hyperthermia in various mouse embryonal carcinoma cell lines and early mouse embryo cells. among the various cell lines tested, two of them, pcc4-aza r1 an ... | 1984 | 6546970 |
| evidence for endogenous reovirus-like particles in a tissue culture cell line from drosophila melanogaster. | | 1980 | 6766592 |
| purification and partial-characterization of a protease inhibitor from drosophila melanogaster. | a protein from drosophila melanogaster which inhibits bovine alpha-chymotrypsin activity was purified using an extensive extraction procedure. sp-sephadex column chromatography and affinity column chromatography. the inhibitor has an estimated molecular weight of approx. 12 000 and is extremely ph and heat stable. it did not exhibit any inhibitory activity against trypsin from numerous sources nor mosquito larval chymotrypsin but did inhibit adult mosquito chymotrypsin. chymotrypsin-like activit ... | 1980 | 6766747 |
| biochemical characterization of phosphoglucose isomerase and genetic variants from mouse and drosophila melanogaster. | a simple and unique procedure was developed to purify phosphoglucose isomerase variants from the whole mouse body extracts and drosophila homogenate. it involved the use of an 8-(6-aminohexyl)-amino-atp-sepharose column followed by a preparative isoelectric focusing. in each case, the enzyme in the homogenate was adsorbed by ionic interaction on the atp-sepharose column. substantial purification was achieved by the affinity elution with the substrate-glucose-6-phosphate. mouse and drosophila pho ... | 1980 | 6767907 |
| multiple forms of drosophila hexokinase. purification, biochemical and immunological characterization. | major forms of hexokinases (hex a and hex c) in drosophila melanogaster were purified to homogeneity by utilizing affinity chromatography and preparative isoelectric focusing column as the key steps. three different affinity ligands immobilized on sepharose (3-amino pyridine adenine dinucleotide, glucosamine, and 8-(6-aminohexyl)-amino-atp) were employed during different stages of enzyme purification. antisera against purified hex a and hex c were raised in rabbits. hex a, the major form in adul ... | 1980 | 6768723 |
| drosophila nuclei replicate in xenopus eggs. | nuclei isolated from a permanent cell line derived from drosophila melanogaster embryos have been injected, along with a radioactive dna precursor [3h]ttp, into xenopus laevis eggs. in culture, less than 7% of the cells were in s phase. after a 90 min incubation, following injection into eggs, 99% of the nuclei were shown by autoradiography to have synthesized dna. in a similar experiment, a density label brdutp was injected into eggs along with the nuclei. subsequent analysis on caesium chlorid ... | 1980 | 6768826 |
| immunological and biochemical analysis of a null mutant of alpha-glycerolphosphate dehydrogenase from drosophila melanogaster. | a drosophila null mutant(bo-1-4) of alpha-glycerolphosphate dehydrogenase induced by ethylmethane sulfonate(ems) was analyzed by double immunodiffusion, enzyme immunoinactivation, immunoelectrophoresis and two-dimensional electrophoresis. based on all the immunological evidence, this mutant appears to express no protein that can cross-react with the antiserum specific to alpha-glycerolphosphate dehydrogenase. a protein spot corresponding to alpha-glycerolphosphate dehydrogenase was identified on ... | 1980 | 6770249 |
| group fractionation and determination of the number of ribosomal subunit proteins from drosophila melanogaster embryos. | proteins were extracted from ribosomes and (for the first time) from ribosomal subunits of drosophila melanogaster embryos. the ribosomal proteins were analyzed by two-dimensional polyacrylamide gel electrophoresis. the electrophoretograms displayed 78 spots for the 80s monomers, 35 spots for the 60s subunits, and 31 spots for the 40s subunits. on the basis of present information, we propose what we believe to be a reliable and convenient nomenclature for the proteins of the ribosomes and each o ... | 1980 | 6770897 |
| the determination of genome size in male and female germ cells of drosophila melanogaster by dna-feulgen cytophotometry. | the amounts of dna in haploid and diploid cells of drosophila melanogaster have been determined by dna-feulgen cytophotometry, using xenopus laevis erythrocyte nuclei as a reference standard. the haploid male genome is estimated to be 0.18 pg dna and the haploid female genome, 0.20 pg dna. | 1980 | 6771237 |
| dna polymerase alpha from drosophila melanogaster embryos. subunit structure. | the homogeneous dna polymerase alpha from early embryos of drosophila melanogaster contains four polypeptides designated alpha, beta, gamma, and delta, with molecular weights of 148,000, 58,000, 46,000, and 43,000, respectively (banks, g. r., boezi, j. a., and lehman, i. r. (1979) j. biol. chem. 254, 9886-9892). the four polypeptides are structurally distinct from one another, as indicated by their different peptide patterns following limited proteolysis with staphylococcus aureus protease. furt ... | 1980 | 6773966 |
| evolution of aldehyde reductase: an immunological approach to the relatedness of aldehyde reductase from different species. | antisera to aldehyde reductase from fruit-fly (drosophila melanogaster) and chicken were cross-reacted with aldehyde reductase from several species of insects and birds using the technique of microcomplement fixation. large differences in immunological distances are evident between species of the class insecta and of the class aves indicating considerable differences in the amino acid sequences of the aldehyde reductase of these species. immunological distances for aldehyde reductase between pai ... | 1980 | 6775512 |
| rna synthesis and coding capacity of polyadenylated and nonpolyadenylated mrna from cultures of differentiating drosophila melanogaster myoblasts. | | 1980 | 6775993 |
| signal peptides and signal peptidase in drosophila melanogaster. | translation of poly(a)-containing rna from the female fat body of drosophila melanogaster in a rabbit reticulocyte cell-free system results in the synthesis of previtellogenin polypeptides (pvs) having higher apparent molecular weights (46,000 and 45,000) than the forms seen after an in vivo pulse labeling. however, when this rna is translated in the presence of edta-stripped microsomal membranes from the dog pancreas, vitellogenin precursors are produced that, upon sds-polyacrylamide gel electr ... | 1980 | 6776130 |
| transfer rna genes of drosophila melanogaster. | three recombinant plasmids containing randomly sheared genomic d. melanogaster trnas have been identified and characterized in detail. one of these, the plasmid 14c4, has a d. melanogaster (dm) dna segment of 18 kb, and has three trna2arg and two trnaasn genes. the second plasmid, 38b10, has trnahis genes, while the third plasmid, 63h5, contains coding sequences for trna2asp. the dm dna segments in each recombinant plasmid are derived from unique cytogenetic loci. 14c4 is from 84 f, 38b10 is fro ... | 1980 | 6776487 |
| an investigation of some genetic toxicological effects of the fungicide benomyl. | the widely used fungicide benomyl (methyl-1-(butylcarbamoyl)-2-benzimidazole carbamate) and its breakdown product methyl-2-benzimidazole carbamate (mbc) have been reported to have mutagenic activity in some organisms. in experiments with drosophila melanogaster we found (i) there was no significant increase in recessive lethal frequency after feeding adult flies with benlate did not increase chromosome breakage or loss significantly; (ii) there was a relatively high incidence of sterility when m ... | 1980 | 6776656 |
| biotransformation and spectral interaction of xenobiotics with subcellular fractions from drosophila melanogaster. | several rapid bioassays are in use to detect, by means of mutagenicity, the formation of reactive metabolites from foreign compounds during their metabolism in the organism. of these bioassays, the fruitfly drosophila melanogaster was investigated with respect to its capacity to biotransform xenobiotics. by spectral analysis it was shown that in microsomal preparations of drosophila the cytochromes p-450 and b5 are present. microsomes appeared to possess aryl hydrocarbon hydroxylase and epoxide ... | 1980 | 6776938 |
| [relationship between an organism's radiosensitivity and its level of repair processes]. | radioresistance and repair intensity were simultaneously studied in 13 stocks of drosophila melanogaster. the frequency of exceptional males in the progeny of x-irradiated females was used as radioresistance criterion. repair intensity was estimated by the radiation after-effect which was determined under successive action of the radiation and elevated temperature (37 degrees c). it has been shown that the higher is the stock radioresistance, the higher are repair capacity of the stock. however, ... | 1980 | 6777252 |
| preliminary studies on the ability of drosophila microsomal preparations to activate mutagens and carcinogens. | subcellular fractions from drosophila melanogaster, known to have several xenobiotic-metabolizing enzymatic activities, were investigated with respect to their ability to biotransform compounds that require metabolic activation before exerting mutagenic effects. nitrofurazone, dimethylnitrosamine, cyclophosphamide and 2-acetylaminofluorene were activated to mutagens upon incubation with drosophila microsomes or 20000 x g supernatant: mutagenicity was observed in chinese hamster ovary cells, esch ... | 1980 | 6777691 |
| double-stranded sequences in rna of drosophila melanogaster: relation to mobile dispersed genes. | double-stranded rna (dsrna) sequences were isolated from either total rna or cytoplasmic poly(a)+rna of d. melanogaster culture cells using a method described previously /1,2/. virtually all dsrna was found to be of high molecular weight (> 200 base pairs) and unable to snap back after rna melting. thus, it corresponds to one of dsrna classes found in mouse cells, namely, to dsrna-a /3/. three different cloned dna fragments of d melanogaster which hybridized to melted dsrna were selected among 1 ... | 1980 | 6777757 |
| isolation and partial characterization of the drosophila alcohol dehydrogenase gene. | the alcohol dehydrogenase (adh; alcohol: nad+ oxidoreductase, ec 1.1.1.1) gene (adh) of drosophila melanogaster was isolated by utilizing a mutant strain in which the adh locus is deleted. adult rna from wild-type flies was enriched in adh sequences by gel electrophoresis and then used to prepare labeled cdna for screening a bacteriophage lambda library of genomic drosophila dna. of the clones that hybridized in the initial screen, one clone was identified that hybridized with labeled cdna prepa ... | 1980 | 6777776 |
| a dispersed multigene family encoding tubulin in drosophila melanogaster. | we have used cloned chicken cdna sequences for alpha- and beta-tubulin to investigate tubulin gene organization in drosophila melanogaster. experiments using genomic drosophila dna from several sources indicate that there are at least four copies each of the alpha-tubulin gene and the beta-tubulin gene. in situ hybridization experiments show that both the alpha- and beta-tubulin multigene families have dispersed arrangements on the chromosome. genes for alpha-tubulin have been localized at chrom ... | 1980 | 6780200 |
| the metabolism of drugs and carcinogens in isolated subcellular fractions of drosophila melanogaster. i. activation of vinyl chloride, 2-aminoanthracene and benzo[a]pyrene as measured by mutagenic effects in salmonella typhimurium. | the capacity of microsomal fractions from different drosophila strains to activate three premutagens, 2-aminoanthracene (2-aa), vinyl chloride (vcm) and benzo[a]pyrene (bp) was investigated, using salmonella typhimurium as the indicator organism. a significant increase in the mutation response in the salmonella test system was obtained with all three substances in the presence of a metabolizing system (s9) from drosophila larvae. 2-aa was converted to highly mutagenic metabolite(s) by the drosop ... | 1981 | 6780204 |
| the metabolism of drugs and carcinogens in isolated subcellular fractions of drosophila melanogaster. ii. enzyme induction and metabolism of benzo[a]pyrene. | | 1981 | 6780205 |
| transmission ratio distortion of mouse t haplotypes is not a consequence of wild-type sperm degeneration. | a mouse t-complex-specific dna probe was used to determine the ratio of t-carrying and (+)-carrying sperm in epididymal, vas deferens, and postejaculatory sperm cell populations from heterozygous (+/t) mice with transmission ratios of greater than 95%. no detectable degeneration of (+)-carrying sperm was observed. in this respect, mouse t haplotypes differ from drosophila melanogaster sd chromosomes. high transmission of t haplotypes must be a consequence of differential transport and/or differe ... | 1984 | 6468763 |
| larval responses to environmental ethanol in drosophila melanogaster: variation within and among populations. | there is a latitudinal cline in attraction to ethanol of newly hatched d. melanogaster larvae; attraction decreases as one moves from the temperature regions to the australian tropics. tropical populations manifest high levels of heterogeneity compared with temperate regions, making tropical populations less dependent on ethanol. since ethanol is a resource for d. melanogaster, an approach to the genetics of resource utilization in natural populations via behavior genetics of larval ethanol resp ... | 1980 | 6783025 |
| analysis of a drosophila trna gene cluster: two trnaleu genes contain intervening sequences. | a recombinant dna phage containing a cluster of drosophila melanogaster trna genes has been isolated and analyzed. the insert of this phage has been mapped by in situ hybridization to chromosomal region 50ab, a known trna site. nucleotide sequencing of the entire drosophila trna coding region reveals seven trna genes spanning 2.5 kb of chromosomal dna. this cluster is separated from other trna regions on the chromosome by at least 2.7 kb on one side, and 9.6 kb on the other. two trna genes are n ... | 1981 | 6783316 |
| biotransformation of xenobiotics in drosophila melanogaster and its relevance for mutagenicity testing. | biotransformation of lipophilic xenobiotics may lead to formation of reactive intermediates which can give rise to irreversible toxic events such as carcinogenesis, mutagenesis, teratogenesis, and tissue necrosis. in recent years considerable attention has been paid to the problem of testing for these effects. short-term mutagenicity tests have been shown to have value for predicting the occurrence of delayed toxic effects in mammals following administration of indirectly acting harmful xenobiot ... | 1980 | 6783378 |
| actin typing on total cellular extracts: a highly sensitive protein-chemical procedure able to distinguish different actins. | based on the finding that the amino-terminal tryptic peptide of actin is a reliable marker for actin divergence, we describe in detail a highly sensitive protein-chemical procedure for actin typing. the method is performed on non-radioactivity labeled cells and tissues and six actins can be identified unambiguously in warm-blooded vertebrates. the method is quantitative and gives directly the ratio of the different actions in the specimens. it does not require previous purification of actin and ... | 1981 | 6783401 |
| histone acetylase from drosophila melanogaster specific for h4. | histone acetylation is a rapid and reversible modification which introduces significant changes in histone-dna interactions. such changes have been correlated with different states of dna transcription and replication in the cell. we have purified a histone acetylase about 1200-fold from extracts of drosophila melanogaster embryos. major steps in the purification include chromatography on histone-sepharose and bio-rex 70. this enzyme, the only histone acetylase detected in these extracts, acetyl ... | 1981 | 6783663 |
| translation of black beetle virus rna and heterologous viral rnas in cell-free lysates derived from drosophila melanogaster. | a cell-free protein synthesizing system was prepared from cells of drosophila melanogaster line 1 and made mrna dependent by treatment with micrococcal nuclease. the system was tested with homologous rna from black beetle virus propagated in drosophila cells, with drosophila heat shock mrna, and with various heterologous viral mrna's. under optimal conditions amino acid incorporation programmed with black beetle virus rnas was 30-fold higher than endogenous incorporation. rnas 1 and 2 primarily ... | 1981 | 6783766 |
| analyses of genetic variants of l-glycerol-3-phosphate dehydrogenase in drosophila melanogaster by two-dimensional gel electrophoresis and immunoelectrophoresis. | a protein spot corresponding to l-glycerol-3-phosphate dehydrogenase (alpha-gpdh, e.c. 1.1.1.8, nad+ oxidoreductase) has been identified on a two-dimensional gel (isoelectric focusing-sds gel) containing up to 150 stained protein spots from a crude drosophila homogenate. preliminary identification of the alpha-gpdh in crude fly homogenates prior to electrophoresis and observing an intensity enhancement of the corresponding protein spot on the gels. when three purified electrophoretic variants (s ... | 1980 | 6784711 |
| orphons: dispersed genetic elements derived from tandem repetitive genes of eucaryotes. | we have discovered in animal cells a novel class of dispersed, solitary genetic elements derived from tandem multigene families. we refer to such displaced elements as orphons. orphons arise from both protein-coding and non-protein-coding structural gene families, including those of histone and ribosomal genes. southern transfer hybridization experiments, on dna digested with enzymes that do not cut the major repeat unit of the family of genes of interest, reveal histone gene orphons in the sea ... | 1981 | 6784929 |
| insulin in insects and annelids. | the fruitfly, drosophila melanogaster, and the earthworm, annelida oligocheta, were extracted with acid-ethanol by a classic method for recovering insulin from the pancreas. when each extract was filtered on a sephadex g-50 column, a distinct peak of insulin immunoreactivity. the material in this peak had reactivity insulin (equivalent to 0.1 to 2 ng of insulin/g wet weight) was recovered in the region typical of insulin bioassay, measuring stimulation of glucose oxidation or lipogenesis by isol ... | 1981 | 6785127 |
| insulin can completely replace serum in drosophila melanogaster cell cultures in vitro. | | 1981 | 6788587 |
| microsomal activation of selected polycyclic aromatic hydrocarbons and aromatic amines in drosophila melanogaster. | benzo[a]pyrene, 7,12-dimethylbenz[a]anthracene, 2-acetylaminofluorene, 2-aminoanthracene, and 1-aminopyrene, when fed to adult drosophila melanogaster males, gave a negative mutagenic response in the x-linked recessive lethal assay. benzo[a]pyrene was also ineffective in inducing "minutes". aflatoxin b1, ems and dmn gave a positive response which was dependent on the concentration of mutagen fed. whole fly homogenates prepared from adult drosophila were assayed for mixed-function oxidase activit ... | 1981 | 6789195 |
| presence of queuine in drosophila melanogaster: correlation of free pool with queuosine content of trna and effect of mutations in pteridine metabolism. | queuine, a modified form of 7-deazaguanine present in certain transfer rnas, is shown to occur in drosophila melanogaster adults in a free form and its concentration varies as a function of age, nutrition and genotype. in several, but not all mutant strains, the concentrations of queuine and the q(+) (queuine-containing) form of trnatyr are correlated. the bioassay employs l-m cells which respond to the presence of queuine by an increase in their q(+)trnaasp that is accompanied by a decrease in ... | 1981 | 6789305 |
| alcohol dehydrogenase gene of drosophila melanogaster: relationship of intervening sequences to functional domains in the protein. | the gene that codes for drosophila alcohol dehydrogenase (adh; alcohol:nad+ oxidoreductase ec 1.1.1.1) was identified in a bacteriophage lambda library of genomic drosophila dna by using adh cdna cloned dna as a probe. the dna sequence of the protein encoding region was shown to be in agreement with the amino acid sequence of the adh. two intervening dna sequences (introns) were identified within the protein encoding region: one was 65 nucleotides and located between the codons for amino acid re ... | 1981 | 6789320 |
| cytosolic glutathione s-transferases in drosophila melanogaster. | post-microsomal supernatants from drosophila melanogaster and rat liver homogenates were investigated with respect to their glutathione s-transferase (gst) activity. it appeared that the drosophila transferase did not conjugate the epoxides styrene-7,8-oxide and 1,2 epoxy-3(p-nitrophenoxy)-propane. attempts to isolate the drosophila gst isozymes by means of the well-documented method for the purification of the rat liver transferases failed, because the drosophila transferases did not bind to cm ... | 1984 | 6439209 |
| proteins of the drosophila melanogaster male reproductive system: two-dimensional gel patterns of proteins synthesized in the xo, xy, and xyy testis and paragonial gland and evidence that the y chromosome does not code for structural sperm proteins. | testes and paragonial glands of drosophila melanogaster wild-type males were labeled in vitro using (35s)methionine, and the proteins synthesized were analyzed by 2-dimensional gel electrophoresis. testes and paragonial glands were also labeled in vivo by feeding male larvae 35s-labeled yeast and then dissecting the adult males. approximately 1200 proteins were resolved by autoradiography of the gels. the in vitro method was shown to be more sensitive and to allow faithful synthesis of all prote ... | 1980 | 6781473 |
| the estimation of epistasis in components of fitness in experimental populations of drosophila melanogaster i. a two-stage maximum likelihood model. | laboratory populations of drosophila melanogaster bearing the curly and plum marked second chromosome inversions were observed in selection experiments for ten discrete generations. maximum likelihood estimates of the relative fitnesses of curly, plum, curly-plum, and wild phenotypes were obtained from selection trajectories. using these estimates, measures of multiplicative and additive epistasis were calculated. these were partitioned into pre-sampling and post-sampling components, and both we ... | 1981 | 6792162 |
| the estimation of epistasis in components of fitness in experimental populations of drosophila melanogaster ii. assessment of meiotic drive, viability, fecundity and sexual selection. | an analysis of fitness components was performed on laboratory populations of drosophila melanogaster bearing curly and plum marked second chromosome inversions with two genetic backgrounds. selective differences between curly, plum, curly-plum, and wild phenotypes were partitioned into meiotic drive, viability, fecundity and mating success. although no significant meiotic drive was detected, there were significant differences between genotypes in the other three components. interlocus interactio ... | 1981 | 6792163 |
| on the mutagenicity of nitroimidazoles. | regarding mutagenicity, metronidazole is one of the best-investigated compounds of the nitroimidazoles. this drug is mutagenic on bacteria, especially if base-pair tester strains are used and bacterial nitroreductases are present. the serum levels attained in man after intake of this drug are sufficient to cause mutations in bacteria. furthermore, interaction with and binding to dna occurs under anaerobic conditions and sometimes dna breaks are observed. however, metronidazole does not show muta ... | 1981 | 6457989 |
| purification and properties of superoxide dismutase from drosophila melanogaster. | the major superoxide dismutase ("slow" electromorph) of the fruit fly, drosophila melanogaster, has been purified to homogeneity. this enzyme contains 2 cu2+ and 2 zn2+/molecule. the ultraviolet absorption spectrum indicates a lack of tryptophan. this enzyme has a molecular weight of 32,000 and is composed of two subunits of equal size, which are joined by noncovalent interactions. cyanide at 1 and 3 mm inhibits the activity of superoxide dismutase 92 and 100%, but 5 and 10 mm azide caused 15 an ... | 1981 | 6790543 |