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CreatorTitleDescriptionSubjectDate
101 Capecchi, Mario R.Isolation and characterization of Caenorhabditis elegans DNA sequences homologous to the v-abl oncogene.DNA sequences homologous to the v-abl oncogene were isolated from a Caenorhabditis elegans genomic library by their ability to hybridize with a v-src probe. The DNA sequence of 2465 nucleotides of one clone was determined. This region corresponds to the 5' protein kinase domain of v-abl plus approxi...Amino Acid Sequence; Animals; Base Sequence; Gene Expression Regulation; Transcription, Genetic1986-04
102 Capecchi, Mario R.Homologous recombination between coinjected DNA sequences peaks in early to mid-S phase.We have examined the effect of cell cycle position on homologous recombination between plasmid molecules coinjected into synchronized rat fibroblasts. Recombination activity was found to be low in G1 and to rise 10- to 15-fold, peaking in early to mid-S phase.Cell Line; Kinetics; Plasmids1986-06
103 Thomas, Kirk R.; Capecchi, Mario R.Introduction of homologous DNA sequences into mammalian cells induces mutations in the cognate gene.Injection of homologous DNA sequences into nuclei of cultured mammalian cells induces mutations in the cognate chromosomal gene. It appears that these mutations result from incorrect repair of a heteroduplex formed between the introduced and the chromosomal sequence. This phenomenon is termed 'heter...Animals; Cell Line; Drug Resistance, Microbial; Fibroblasts; Mice; Models, Genetic; Neomycin; Plasmids1986-11-06
104 Jorgensen, ErikFunction and misfunction of the two promoters of the Drosophila Antennapedia geneIn the Antennapedia (Antp) gene of Drosophila melanogaster, structurally distinct RNAs arise from different transcription initiation sites. When the two sites are separated by a chromosome inversion, transcripts are produced from each fragment of the split Antp locus, and these RNAs initiate at the ...RNA; Antp; Hybridization1987
105 Coley, Phyllis D.Patrones en las defensas de las plantas: ? Porque los herbivoros prefrieren ciertas especies?Patterns of heitmory and plant defenses arc presented lor 47 tree species studied on Barro Colorado Island, Panama. Species growing In comparable microhabitats differ in the rates of herbivore damage by 4 orderi of magnitude. Over 70%QT these between-specles differences in herbivory can be explaine...1987
106 Olivera, Baldomero M.; Gray, William Robert; McIntosh, J. MichaelNeuronal calcium channel inhibitors: synthesis of ω-conotoxin GVIA and effects on 45Ca-uptake by synaptosomesWe previously described a 27-amino acid peptide neurotoxin from the venom of Conus geographus, wconotoxin GVIA, which inhibits neuronal voltage-activated calcium channels. In this paper we describe the total synthesis of ω-conotoxin GVIA and demonstrate that it efficiently blocks voltage-activat...Neuronal calcium; Calcium channels; Channel inhibitors; [omega]-conotoxin GVIA1987
107 Olivera, Baldomero M.Biochemical studies of ω-conotoxin GVIA; a peptide toxin inhibiting voltage-sensitive Ca++ channelsThe fish-hunting cone snails use their venom to quickly paralyze their more agile prey. In the last few years, our laboratories have carried out a program of analyzing biologically active components present in the fish-hunting cone snail venoms (Cruz et al. 1985; Olivera et al. 1985). We have concen...Conotoxins; Calcium channels; Conus geographus; Venom1987
108 Olivera, Baldomero M.Aminoglycoside effects on voltage-sensitive calcium channels and neurotoxicityTo the Editor: Since ototoxicity and neuromuscular toxicity of aminoglycoside antibiotics are reversed by calcium, 1,2 and presynaptic events appear to be involved in aminoglycoside-induced neuromuscular blockade, 3,4 we suspected a role for voltage-sensitive calcium channels in aminoglycoside neuro...Conotoxins1987
109 Olivera, Baldomero M.; Gray, William RobertInvertebrate vasopressin/oxytocin homologs: characterization of peptides from Conus geographus and Conus striatus venomsThe vasopressin-oxytocin family of peptides is of very ancient lineage, found in organisms as diverse as hydra and man. Although these peptides have been intensively studied in vertebrates, the presumably more extensive invertebrate series was defined primarily by immunological methods. In this repo...Conus geographus; Conus striatus; Venom; Conotoxins; Neurotoxins; Postsynaptic inhibition; Vasopressin-oxytocin peptides; Conopressin1987
110 Capecchi, Mario R.; Thomas, Kirk R.Site-directed mutagenesis by gene targeting in mouse embryo-derived stem cellsWe mutated, by gene targeting, the endogenous hypoxanthine phosphorlbosyl transferase (HPFlT) gene in mouse embryo-derived stem (ES) cells. A specialized construct of the neomycin resistance (NO') gene was introduced into an exon of a cloned fragment of the Hprf gene and used to transfect ES cell...Site-directed mutagenesis; Hypoxanthine phosphorlbosyl transferase gene; HPFlT gene; Neomycin resistance gene; Homologous recombination; Mouse stem cells; Mouse embryo-derived stem cells1987
111 Gesteland, Raymond F.; Atkins, John F.; Weiss, Robert B.Slippery runs, shifty stops, backward steps and forward hops: -2, -1, +1, +2, +5 and +6 Ribosomal frameshiftingFrameshift mutations frequently express residual levels of gene activity; that is, they are often leaky. This leakiness can be used as a tool to define the functional components that affect the reading frame during gene expression. Recent technological advances in the capability to efficiently bu...Molecular Sequence Data; Mutation; RNA, Transfer; Frameshifting1987
112 Coley, Phyllis D.Between-species differences in leaf defenses of tropical treesRates of herbivory and patterns of leaf defense are presented for light-demanding and shade-tolerant tree species growing in a lowland rainforest in Panama. More than 85 percent of the annual leaf damage is due to grazing by insects. There are over three orders of magnitude difference between specie...Herbivory; Interspecific variation; Panama; Growth rate; Shade tolerance; Treefall gaps; Tropical forest; Understory; Tannins; Alkaloids1987
113 Bohs, Lynn A.Four new species of Cyphomandra (Solanaceae) from South AmericaFour new species in the Neotropical genus Cyphomandra are described and illustrated. Cyphomandra pilosa and C. foetida are found on the eastern slopes of the Andes from Colombia to Peru. Cyphomandra oblongifolia is a morphologically variable species of Suriname and the Amazon basin. Cyphomandra sib...Cyphomandra1988
114 Davidson, Diane W.Pruning of host plant neighbors by ants: an experimental approachSome ants of myrmecophytic plants either obligately or facultatively prune vegetation surrounding their host trees. Pruning behavior occurs at higher frequency in ants with sting defenses than in those with chemical defenses, which may generally convey an advantage in aggressive encounters between a...Allelopathy; Allomerus demararae; Ant-plant interactions; Ants; Cordia nodosa; Crematogaster; Mutualism; Peru; Plant-animal interaction; Pseudomyrmex; Triplaris americana1988
115 Davidson, Diane W.Ecological studies of neotropical ant-gardensIn a census taken in Peru's Manu National Park, 10 epiphytic angiosperms from seven plant families established principally on arboreal carton-ant nests. These "ant gardens" (AGs) were most often inhabited by parabiotic ants, Camponotus femoratus and Crematogaster cf. limata parabiotica, whose polygy...Ant competition; Ant garden; Ant-plant interaction; Coadaptation; Epiphyte; Mutualism; Parabiosis; Preadaptation; Peru; Seed dispersal; Tropical rainforest1988
116 Bastiani, MichaelCentral projections of the stretch receptor neurons of crayfish: structure, variation, and postembryonic growthEach stretch receptor neuron (SR) of the crayfish abdomen projects from its peripherally located soma an axon that enters the CNS through the second nerve (N2) of its segmental ganglion. CoZ+ backfills of N2 revealed that this axon bifurcates, sending one branch to the brain and the other to the te...Abdomen; Axon; Ganglion1988
117 Sperry, John S.Seasonal occurrence of xylem embolism in sugar maple (Acer saccharum)Xylem embolism, the reduction of water flow by air-filled vessels, was measured in a stand of 5- to 8-year-old sugar maple (Acer saccharum Marsh.) saplings growing in a nursery bed in northwestern Vermont. Embolism was quantified as percentage loss in hydraulic conductivity of trunk and branch seg...Xylem pressure; root pressure; dye perfusion1988
118 Hughes, Kelly T.Phase variation in Salmonella: analysis of Hin recombinase and hix recombination site interaction in vivoThe bacteriophage P22-based challenge phase selection was used to characterize the binding of Salmonella Hin recombinase to the wild-type hixL and hixR recombination sites, as well as to mutant and synthetic hix sequences in vivo. Hin recombinase binds to the hixL or hixR recombination sites and rep...1988
119 Bastiani, MichaelCentral projections of the stretch receptor neurons of crayfish: segmental gradients of synaptic probability and strengthThe 20 stretch receptor neurons (SRs) of the crayfish abdomen send axons into the CNS that then project both to the brain and to the last abdominal ganglion, G6 (Bastiani and Mulloney, 1988). In G6, we recorded intracellularly from different kinds of neurons postsynaptic to SR axons.Axons; Synapses; SR1988
120 Seger, JonEvolution of individuality by Leo W. BussMetazoans seldom reproduce vegetatively; they often die of cancer; and they almost always sequester their germ lines. Plants often reproduce vegetatively, seldom die of cancer, and almost never sequester a germ line. Buss argues that these and many other patterns can all be understood in a unified w...Cell lines; Hierarchy; Biology1988
121 Davidson, Diane W.Comparative structure of harvester ant communities in arid Australia and North AmericaIn the Australian arid zone, the species richness of ants is greater and that of mammalian granivores is less than in North American deserts. This study aimed to determine if the structure of harvester ant communities differs from that seen in North American deserts, focussing on differences relate...Species; Rodents; Diversity1988
122 Seger, JonParasites and sexParasites of many kinds have long been recognized as important regulators of population size (e.g., May, 1983b), but only during the last decade or two have they been widely viewed as the protagonists in fast-paced (and long-running) evolutionary thrillers involving subtle features of the biochemis...Cost of sex1988
123 Capecchi, Mario R.; Mansour, Suzanne L.; Thomas, Kirk R.Disruption of the proto-oncogene int-2 in mouse embryo-derived stem cells: a general strategy for targeting mutations to non-selectable genes.Gene targeting--homologous recombination of DNA sequences residing in the chromosome with newly introduced DNA sequences--in mouse embryo-derived stem cells promises to provide a means to generate mice of any desired genotype. We describe a positive nd negative selection procedure that enriches 2,00...Animals; Clone Cells; Restriction Mapping; Stem Cells1988-11-24
124 Coley, Phyllis D.Red coloration of tropical young leaves: a possible antifungal defense?Many woody species in humid tropical forests synchronously flush entire canopies of young red leaves. Numerous unsuccessful attempts have been made to explain the adaptive value of this visually striking phenomenon. In the humid tropics, fungal attack is a potentially important source of mortality f...Herbivory; Anthocyanin; Antifungal defense; Atta columbica; Panama; Leaf-cutting ants; Tropics; Young leaves1989
125 Potts, Wayne K.Consequences of self and foreign superantigen interaction with specific VB elements of the murine TCR aBThe aB T-cell receptor (TCRaB) recognizes a ligand composed of an antigen fragment complexed with a product of the major histocompatibility complex (MHC). The repertoire of receptors is limited both by the germ line of receptor variable elements and by selective events that take place during T-cell ...Toxins; Repertoire; Expression1989
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