Implementation of two high through-put techniques in a novel application: detecting point mutations in large EMS mutated plant populations

Background  

The establishment of mutant populations together with the strategies for targeted mutation detection has been applied successfully to a large number of organisms including many species in the plant kingdom. Considerable efforts have been invested into research on tomato as a model for berry-fruit plants. With the progress of the tomato sequencing project, reverse genetics becomes an obvious and achievable goal.     

Brain grafts reduce motor abnormalities produced by destruction of nigrostriatal dopamine system

In order to determine if brain tissue grafts can provide functional input to recipient central nervous system tissue, fetal rat dopamine-containg neurons were implanted adjacent to the caudate nucleus of adult recipients whose endogenous dopaminergic input had been destroyed. The grafts showed good survival and axonal outgrowth. Motor abnormalities, which had been induced by the destruction of the endogenous dopaminergic input to the caudate, were significantly reduced after grafting of the fetal brain tissue. These data suggest that such implants may be potentially useful in reversing deficits after circumscribed destruction of brain tissue.     

The Leukocytes of the Roughtail Gecko Cyrtopodion scabrum: a Bright-field and Phase-contrast Study

The morphology of the peripheral blood leukocytes of the roughtail gecko, Cyrtopodion scrabum, is carefully described in Wright-Giemsa and toluidine-blue-stained blood films, and in the living condition by phase-contrast microscopy, using supravitally stained preparations. Mature eosinophils, basophils and small lymphocytes commonly occur in the blood, while monocytes are rarely seen. In addition, macrophages are occasionally encountered, but neutrophils cannot be observed. Developmental stages in eosinophil and basophil differentiation can be seen. This study serves as a basis for the cytochemical localization of substances within these blood cells.     

Phosphorescence Spectra and Analyses of Some Indole Derivatives

Phosphorescence spectra of solutions frozen and at low temperatures (77 degrees K) possess more characteristic structure and detail than fluorescence spectra. They contain no background due to scattering of the exciting radiation. Thus greater analytical specificity and sensitivity are obtained. Some indole derivatives indistinguishable by spectrofluorimetry are easily differentiated by spectrophosphorimetry.     

Topography of the northern hemisphere of Mercury from MESSENGER laser altimetry

Laser altimetry by the MESSENGER spacecraft has yielded a topographic model of the northern hemisphere of Mercury. The dynamic range of elevations is considerably smaller than those of Mars or the Moon. The most prominent feature is an extensive lowland at high northern latitudes that hosts the volcanic northern plains. Within this lowland is a broad topographic rise that experienced uplift after plains emplacement. The interior of the 1500-km-diameter Caloris impact basin has been modified so that part of the basin floor now stands higher than the rim. The elevated portion of the floor of Caloris appears to be part of a quasi-linear rise that extends for approximately half the planetary circumference at mid-latitudes. Collectively, these features imply that long-wavelength changes to Mercury's topography occurred after the earliest phases of the planet's geological history.     

Effect of DDT on photosynthesis of Selanastrum capricormutum

The effect of DDT (2,2-bis-(p-chlorophenyl)-1,1,1-trichloroethane) on carbon assimilation of a green alga, Selanastrum capricormutum was studied. DDT at concentrations between 3.6 and 36 ppb was inhibitory to the photosynthetic CO₂ fixation (ethanol-soluble and/or ethanol-insoluble) and the longer the exposure to DDT, the greater the inhibition. Kinetic studies of photosynthetic CO₂ fixation indicated that DDT stimulated the incorporation of carbon-14 into glycolic acid, a major compound of photorespiration and caused the concomittant suppression of flow of carbon-14 into aspartic acid, a major component of the C₄-dicarboxylic acid pathway. The shift from an efficient pathway into a nonefficient pathway by DDT was interpreted to be through interruption of cyclic photophosphorylation.