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CreatorTitleDescriptionSubjectDate
51 Olivera, Baldomero M.; McIntosh, J. Michael; Hillyard, David R.A-superfamily of conotoxins: structural and functional divergenceThe generation of functional novelty in proteins encoded by a gene superfamily is seldom well documented. In this report, we define the A-conotoxin superfamily, which is widely expressed in venoms of the predatory cone snails (Conus), and show how gene products that diverge considerably in stru...Conotoxins; A-superfamily conotoxin2004-02-03
52 Shapiro, Michael D.Adaptive evolution of pelvic reduction in sticklebacks by recurrent deletion of a Pitx1 enhancerThe molecular mechanisms underlying major phenotypic changes that have evolved repeatedly in nature are generally unknown. Pelvic loss in different natural populations of threespine stickleback fish has occurred by regulatory mutations deleting a tissue-specific enhancer of the Pituitary homeobox t...Adaptive evolution; Pelvic reduction; Pituitary homeobox transcription factor 1; Pitx1; Gasterosteus aculeatus2010-01-14
53 Capecchi, Mario R.Fundamental cellular processes do not require vertebrate-specific sequences within the TATA-binding protein.The 180-amino acid core of the TATA-binding protein (TBPcore) is conserved from Archae bacteria to man. Vertebrate TBPs contain, in addition, a large and highly conserved N-terminal region that is not found in other phyla. We have generated a line of mice in which the tbp allele is replaced with a v...Mice, Knockout; Cells, Cultured; Fibroblasts; Embryo2003-02-21
54 Capecchi, Mario R.Hox group 3 paralogous genes act synergistically in the formation of somitic and neural crest-derived structures.Hox genes encode transcription factors that are used to regionalize the mammalian embryo. Analysis of mice carrying targeted mutations in individual and multiple Hox genes is beginning to reveal a complex network of interactions among these closely related genes which is responsible for directing th...Abnormalities, Multiple; Gene Targeting; Glossopharyngeal Nerve; Mice, Knockout; Morphogenesis1997-12-15
55 Linton, Matthew J.Magnitude and mechanisms of disequilibrium between predawn plant and soil water potentialsPredawn plant water potential (Uw, measured with leaf psychrometers) and surrogate measurements made with the pressure chamber (termed Upc here) are used to infer comparative ecological performance, based on the expectation that these plant potentials reflect the wettest soil Uw accessed by roots. T...Roots; Transpiration; Solutes2003
56 Adler, Frederick R.Alternating host cell tropism shapes the persistence, evolution and coexistence of Epstein-Barr virus infections in humanEpstein-Barr virus (EBV) infects and can persist in a majority of people worldwide. Within an infected host, EBV targets two major cell types, B cells and epithelial cells, and viruses emerging from one cell type preferentially infect the other. We use mathematical models to understand why EBV infec...2011
57 Olivera, Baldomero M.; Gray, William RobertContryphan is a D-tryptophan-containing Conus peptideIn this report, we document for the first time the occurrence of D-tryptophan in a normally translated polypeptide, contryphan. The peptide, isolated from the venom of the fish-hunting marine snail Conus radiatus, produces the "stiff-tail" syndrome in mice.Conotoxins; Contryphan; D-tryptophan; Conus peptides; Conus radiatus; Stiff-tail syndrome1996
58 Goller, FranzRespiratory motor correlates of song plasticity in young adult zebra finchesYoung adult zebra finches (Taeniopygia guttata, 90150 phd) sing a stereotyped song, but can show rapid changes in song structure if sensory feedback is disrupted. The vocal motor correlates accompanying induced song plasticity have not yet been examined. To investigate motor changes underlying song ...Pattern; Muting; Sound2002
59 Capecchi, Mario R.Hox genes and mammalian developmentWe have examined the interactions of Hox genes in forming a cervical vertebrae, hindbrain, and limbs. In each case, it is apparent that individual Hox genes are performing individual functions but that more profound roles are apparent when they act in combination with others Hox genes. The observed ...Drosophila; Gene Expression Regulation, Developmental; Homozygote1997
60 Olivera, Baldomero M.; Hillyard, David R.; Gray, William Robertĸ-Conotoxin PVIIA is a peptide inhibiting the Shaker K+ channelĸ-Conotoxin PVIIA (k-PVIIA), a 27-amino acid toxin from Conus purpurascens venom that inhibits the Shaker potassium channel, was chemically synthesized in a biologically active form. The disulfide connectivity of the peptide was determined. ĸ-Conotoxin PVIIA has the following structure.Conotoxins; k-Conotoxin PVIIA; Conus purpurascens1998
61 Frederick, Jeanne M.; Baehr, WolfgangReceptor for advanced glycation end products and age-related macular degeneration.Advanced glycation end products (AGE) exacerbate disease progression through two general mechanisms: modifying molecules and forming nondegradable aggregates, thus impairing normal cellular/tissue functions, and altering cellular function directly through receptor-mediated activation. In the present...Optic Atrophies, Hereditary; Apoptosis; Pigment Epithelium of Eye2004
62 Adler, Frederick R.Effect of 1918 PB1-F2 expression on influenza A virus infection kineticsRelatively little is known about the viral factors contributing to the lethality of the 1918 pandemic, although its unparalleled virulence was likely due in part to the newly discovered PB1-F2 protein. This protein, while unnecessary for replication, increases apoptosis in monocytes, alters viral po...2011
63 Sperry, John S.Relationship between xylem conduit diameter and cavitation caused by freezingThe centrifuge method for measuring the resistance of xylem to cavitation by water stress was modified to also account for any additional cavitation that might occur from a freeze-thaw cycle. A strong correlation was found between cavitation by freezing and mean conduit diameter.Embolism; freezing stress; hydraulic conductivity1999
64 Bastiani, MichaelPathfinding by growth cones in the central nervous system of the grasshopper embryoIn the grasshopper embryo the morphological development of individually identified neurons can be traced prior to the onset of axonogenesis on through maturity (eg., Goodman and Spitzer, 1979). The behavior of individual growth cones can be characterized in their natural environment as they extend t...1982-06-03
65 Capecchi, Mario R.Lack of angiotensin II-facilitated erythropoiesis causes anemia in angiotensin-converting enzyme-deficient miceWhile nephrologists often observe reduced hematocrit associated with inhibitors of angiotensin-converting enzyme (ACE), the basis for this effect is not well understood. We now report that two strains of ACE knockout mice have a normocytic anemia associated with elevated plasma erythropoietin level...2000
66 Sekercioglu, CaganThe need to quantify ecosystem services provided by birdsWhat are birds worth-what is their actual dollar value to human society? To most of us in the ornithological community, birds are invaluable. But in these times we need more specific rationales to convince policy makers and business leaders to include bird conservation in land-use and development de...2011-01-01
67 Clayton, Dale H.New genus and three new species of chewing lice (Phthiraptera: Philopteridae) from Peruvian ovenbirds (Passeriformes: Furnariidae)The new genus Furnariphilus is described to include three new species from Peruvian hosts within the passerine family Furnariidae, subfamily Furnariinae: F. pagei, the type species of the genus, from Furnarius leucopus Swainson; F. griffithsi from Sclerurus mexicanus Sclater; and F. parkeri from Scl...Chewing lice; Peruvian ovenbirds; Phthiraptera; Furnariphilus; Ectoparasites; Peru; Furnarius leucopus; Sclerurus mexicanus; Sclerurus caudacutus1995
68 Adler, Frederick R.How virulent should a parasite be to its vector?Vector-borne parasites are commonly predicted to be less virulent to the vector than to the definitive host as the parasite gains little by harming its main route of transmission. Here we assess the empirical evidence from systems in which insects are vectors for vertebrate, plant, and invertebrate ...Parasite virulence; Hosts; Vector-borne parasite2003
69 Goller, FranzLow-dimensional dynamical model for the diversity of pressure patterns used in canary songDuring song production, oscine birds produce large air sac pressure pulses. During those pulses, energy is transferred to labia located at the juncture between the bronchii and the trachea, inducing the high frequency labial oscillations which are responsible for airflow modulations, i.e., the utt...Serinus canarias; Air sac pressure2009-04
70 Goller, FranzSynthesizing bird songIn this work we present an electronic syrinx: an analogical integrator of the equations describing a model for sound production by oscine birds. The model depends on time varying parameters with clear biological interpretation: the air sac pressure and the tension of ventral syringeal muscles. We te...Syrinx; Tension; Transducer2005
71 Adler, Frederick R.Genetic and phylogenetic consequences of island biogeographyIsland biogeography theory predicts that the number of species on an island should increase with island size and decrease with island distance to the mainland. These predictions are generally well supported in comparative and experimental studies. These ecological, equilibrium predictions arise as a...Extinction; Genetic divergence; Island isolation; Migration; Speciation2000
72 Thomas, Kirk R.; Capecchi, Mario R.Location of crossovers during gene targeting with insertion and replacement vectors.Gene targeting was used to introduce nonselectable genetic changes into chromosomal loci in mouse embryo-derived stem cells. The nonselectable markers were linked to a selectable marker in both insertion- and replacement-type vectors, and the transfer of the two elements to the Hprt locus was assaye...Genetic Vectors; Molecular Sequence Data; Restriction Mapping1993-04
73 Olivera, Baldomero M.; McIntosh, J. MichaelNovel post-translational modification involving bromination of tryptophan: identification of the residue, L-6-bromotryptophan, in peptides from Conus imperialis and Conus radiatus venomWe report a novel post-translational modification involving halogenation of tryptophan in peptides recovered from the venom of carnivorous marine cone snails (Conus). The residue, L-6-bromotryptophan, was identified in the sequence of a heptapeptide, isolated from Conus imperialis, a worm-hunting...Conotoxins; Conus imperialis; Conus radiatus; L-6-bromotryptophan1997
74 Ehleringer, James R. ; Cerling, Thure E.Aberrant water homeostasis detected by stable isotope analysisWhile isotopes are frequently used as tracers in investigations of disease physiology (i.e., 14C labeled glucose), few studies have examined the impact that disease, and disease-related alterations in metabolism, may have on stable isotope ratios at natural abundance levels. The isotopic composition...2010-07-21
75 Sperry, John S.Xylem hydraulics and the soil-plant-atmosphere continuum: opportunities and unresolved issuesReceived for publication July 23, 2002. Soil and xylem are similar hydraulically. An unsaturated conductivity curve for soil is called a vulnerability curve for xylem?but the underlying physical basis is the same. Thus, any transport model that treats unsaturated soil conductivity would benefit by a...Soil?plant?atmosphere continuum; Water potential2003
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