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CreatorTitleDescriptionSubjectDate
1 Sperry, John S.Anatomy of the palm Rhapis excelsa, IX. Xylem structure of the leaf insertionSTEMS OF PERENNIAL PLANTS, particularly trees, represent a considerable investment in biomass. Trees can survive even under the most adverse conditions, but only if the hydraulic integrity of the stem is preserved. A very important and vulnerable part of the stem is the xylem. As water is pulled int...Palm stems; Palm stem anatomy; Palm leaves; Leaf insertion; Vessel network; Vessel-length distribution; Primary vascular stem tissue; Hydraulic architechture; Water column1983
2 Sperry, John S.Evolution of water transport and xylem structureLand plants need water to replace the evaporation that occurs while atmospheric CO2 is diffusing into photosynthetic tissue. The water-for-carbon exchange rate is poor, and evolutionary history indicates a progression of innovations for cheap water transport--beginning in order with capillary sucti...Cavitation; Vessels; Plants2003
3 Sperry, John S.Analysis of circular bordered pit function I. Angiosperm vessels with homogenous pit membranesA model predicted pit and vessel conductivity, the air-seed pressure for cavitation, and the implosion pressure causing vessel collapse. Predictions were based on measurements from 27 angiosperm species with circular bordered pits and air-seed pressures of 0.2-11.3 MPa. Vessel implosion pressure exc...Functional wood anatomy; hydraulic architecture; plant biomechanics2004
4 Sperry, John S.Analysis of circular bordered pit function II. Gymnosperm tracheids with torus-margo pit membranesA model of xylem conduit function was applied to gymnosperm tracheids with torus-margo pit membranes for comparison with angiosperm vessels. Tracheids from 17 gymnosperm tree species with circular bordered pits and air-seed pressures from 0.8 to 11.8 MPa were analyzed. Tracheids were more reinforced...Functional wood anatomy; hydraulic architecture; plant biomechanics2004
5 Sperry, John S.Size and function in conifer tracheids and angiosperm vesselsThe wide size range of conifer tracheids and angiosperm vessels has important consequences for function. In both conduit types, bigger is better for conducting efficiency. The gain in efficiency with size is maximized by the control of conduit shape, which balances end-wall and lumen resistances.Ecological wood anatomy; vascular structure and function; water transport2006
6 Gesteland, Raymond F.; Atkins, John F.; Wills, Norma M.rRNA-mRNA base pairing stimulates a programmed -1 ribosomal frameshiftBase pairing between the 3' end of 16S rRNA and mRNA is shown to be important for the programmed -1 frameshifting utilized in decoding the Escherichia coli dnaX gene. This pairing is the same as the Shine-Dalgarno pairing used by prokaryotic ribosomes in selection of translation initiators, but for ...Frameshifting; Escherichia coli; Binding Sites; Base Composition1994
7 Gesteland, Raymond F.; Atkins, John F.; Ingram, Jennifer A.; Kelly, Paul J.; Grentzmann, GuidoDual-luciferase reporter system for studying recoding signalsA new reporter system has been developed for measuring translation coupling efficiency of recoding mechanisms such as frameshifting or readthrough. A recoding test sequence is cloned in between the renilla and firefly luciferase reporter genes and the two luciferase activities are subsequently measu...Amino Acid Sequence; Genes, Reporter; HIV; Antizyme; Translation1998
8 Adler, Frederick R.Migration alone can produce persistence of host-parasitoid modelsIt has long been recognized that the unstable equilibrium of a single-patch predator-prey model cannot be stabilized by diffusive coupling with identical patches, since the coupled system acts exactly like the single-patch system if the patches are synchronized (Maynard Smith 1974; Allen 1975; Reeve...Heterogeneity; Nicholson-Bailey; migration rates1993
9 Beckerle, Mary C.ALP-enigma protein ALP-1 functions in actin filament organization to promote muscle structural integrity in Caenorhabditis elegansMutations that affect the Z-disk-associated ALP-Enigma proteins have been linked to human muscular and cardiac diseases. Despite their clear physiological significance for human health, the mechanism of action of ALP-Enigma proteins is largely unknown. In Caenorhabditis elegans, the ALP-Enigma prot...Actin; Caenorhabditis elegans; Contractility; alp-1 mutants; Z-disks; Kettin2009
10 Beckerle, Mary C.LIM proteins in actin cytoskeleton mechanoresponseThe actin cytoskeleton assembles into branched networks or bundles to generate mechanical force for critical cellular processes such as establishment of polarity, adhesion, and migration. Stress fibers are contractile, actomyosin structures that physically couple to the extracellular matrix through ...2014-01-01
11 Sperry, John S.Evaluation of Murray's law in Psilotum nudum (Psilotaceae), an analogue of ancestral vascular plantsPrevious work has shown that the xylem of seed plants follows Murray's law when conduits do not provide structural support to the plant. Here, compliance with Murray's law was tested in the stem photosynthesizer Psilotum nudum, a seedless vascular plant. Psilotum nudum was chosen because the central...Conduit furcation number; hydraulic architecture; Murray's law2005
12 Sperry, John S.Inter-tracheid pitting and the hydraulic efficiency of conifer wood: the role of tracheid allometry and cavitation protectionPlant xylem must balance efficient delivery of water to the canopy against protection from air entry into the conduits via air-seeding. We investigated the relationship between tracheid allometry, end wall pitting, safety from air-seeding, and the hydraulic efficiency of conifer wood in order to bet...Allometry; Araucariaceae; cavitation2006
13 Sperry, John S.Hydraulic architecture of palmsThe water transport and storage system of palms is adapted to maintain the primary stem xylem functional over the life of the shoot, and in spite of severe drought. However, our structural information far exceeds our knowledge of vascular function, and these functional considerations bring more que...Hydraulic architecture; Rhapis excelsa; Cavitation1995
14 Farmer, Colleen G.; Carrier, David R.Integration of ventilation and locomotion in archosaursMovements of the pelvis have recently been found to contribute to ventilation in both crocodilians and birds. Alligators have a kinetic pelvis in which the ischiopubic and ischiotruncus muscles rotate the pubic bones ventrally to increase abdominal volume and thereby facilitate inspiration. In birds...Archosaurs; Theropods; Integration; Ventilation; Pelvic aspiration; Cuirassal breathing2000
15 Capecchi, Mario R.Establishment of mammalian cell lines containing multiple nonsense mutations and functional suppressor tRNA genes.We describe the generation of mammalian cell lines carrying amber suppressor genes. Nonsense mutants in the herpes simplex virus thymidine kinase (HSV tk) gene, the Escherichia coli xanthine-guanine phosphoribosyl transferase (Eco-gpt) gene and the aminoglycoside 3' phosphotransferase gene of the Tn...Cercopithecus aethiops; Escherichia coli; Xenopus1982-11-30
16 Blair, David F.Metal centers of cytochrome c oxidase: structures and interactionsStudies directed toward the elucidation of the structures of the metal centers in cytochrome c oxidase are reviewed. Progress towards an understanding of the interactions between these centers and their spatial distributions within the protein will also be presented. Our studies are based primarily...1983
17 Sperry, John S.Cavitation fatigue - the weakening of cavitation resistance of xylem and its reversibilityXylem function is essential for the growth and survival of higher land plants. Xylem must not only be efficient under favorable conditions to facilitate high rates of stomatal conductance and carbon uptake, but it should also remain functional under drought conditions, when water potential (Ψ) dro...Cavitation fatigue; Drought; Pit membrane2003
18 Parkinson, John StansfieldAn unorthodox sensory adaptation site in the E. coli serine chemoreceptorThe serine chemoreceptor of E. coli contains four canonical methylation sites for sensory adaptation that lie near inter-subunit helix interfaces of the Tsr homodimer. An unexplored fifth methylation site, E502, lies at an intra-subunit helix interface, closest to the HAMP domain that controls input...2014-01-01
19 Sperry, John S.Water transport in vesselless angiosperms: conducting efficiency and cavitation safetyTwo structure-function hypotheses were tested for vesselless angiosperm wood. First, vesselless angiosperm wood should have much higher flow resistance than conifer wood because angiosperm tracheids lack low-resistance torus-margo pits. Second, vesselless wood ought to be exceptionally safe from cav...2007
20 Farmer, Colleen G.The provenance of alveolar and parabronchial lungs: insights from paleoecology and the discovery of cardiogenic, unidirectional airflow in the American alligator (Alligator mississippiensis)Birds and mammals evolved greater aerobic abilities than their common ancestor had. This required expansion of the cardiopulmonary system's capacity for gas exchange, but while directional selection for his expanded capacity resulted in extremely similar avian and mammalian hearts, strikingly differ...2010-07
21 Beckerle, Mary C.; Clark, Kathleen A.Conserved LIM protein that affects muscular adherens junction integrity and mechanosensory function in Caenorhabditis elegansWe describe here the molecular and functional characterization of the Caenorhabditis elegans unc-97 gene, whose gene product constitutes a novel component of muscular adherens junctions. UNC-97 and homologues from several other species define the PINCH family, a family of LIM proteins whose modula...LIM domains; Caenorhabditis elegans; UNC-97; Adherens junction; Touch neuron; Muscle development1999
22 Capecchi, Mario R.Mice lacking endothelial angiotensin-converting enzyme have a normal blood pressureTo test the hypothesis that local vascular production of angiotensin II is necessary for the normal regulation of blood pressure, we engineered a new line of genetically altered mice that lack endothelial angiotensin-converting enzyme (ACE). This was accomplished using a novel strategy of targeted...2002
23 Olivera, Baldomero M.On the mechanism of the polynucleotide joining reactionPolynucleotide-joining enzymes (ligases) have been identified in uninfected and phage-infected Escherichia coli (Gellert, 1967; Olivera and Lehman, 1967a; Zimmerman et al., 1967; Gefter et al., 1967; Weiss and Richardson, 1967a; Cozzarelli et al., 1967). Both types of enzyme catalyze the synthesis o...Enzyme-AMP; Enzyme-Adenylate; DNA-Adenylate; Poly dt-Adenylate; Pyrophosphate bond1968
24 Clayton, Dale H.Experimental test of the importance of preen oil in Rock Doves (Columba livia)Most species of birds have a uropygial gland, also known as a preen gland, which produces oil that birds spread through their plumage when preening. The plumage of waterfowl deprived of uropygial oil becomes brittle and is subject to breakage.Columba livia; Columbiformes; Preen oil; Ectoparasites; Columbicola columbae; Campanulotes compare; Plumage2003
25 Jorgensen, ErikNano-fEM: Protein localization using photo-activated localization microscopy and electron microscopyMapping the distribution of proteins is essential for understanding the function of proteins in a cell. Fluorescence microscopy is extensively used for protein localization, but subcellular context is often absent in fluorescence images. Immuno-electron microscopy, on the other hand, can localize pr...2012-01-01
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