An S-receptor kinase (SRK) cDNA, SRK-910, from the active S-locus in a self-incompatible Brassica napus W1 line has been isolated and characterized. The SRK-910 gene is predominantly expressed in ...pistils and segregates with the W1 self-incompatibility phenotype in an F2 population derived from a cross between the self-incompatible W1 line and a self-compatible Westar line. Analysis of the predicted amino acid sequence demonstrated that the extracellular receptor domain is highly homologous to S-locus glycoproteins, whereas the cytoplasmic kinase domain contains conserved amino acids present in serine/threonine kinases. An SRK-910 kinase protein fusion was produced in Escherichia coli and found to contain kinase activity. Phosphoamino acid analysis confirmed that only serine and threonine residues were phoshorylated. Thus, the SRK-910 gene encodes a functional serine/threonine receptor kinase
Self-Rejection: A New Kinase Connection Goring, Daphne R.; Walker, John C.
Science (American Association for the Advancement of Science),
03/2004, Letnik:
303, Številka:
5663
Journal Article
Recenzirano
Goring and Walker examine the study of Murase et al on the report of a new player--the M locus protein kinase (MLPK)--in the self-incompatibility signaling pathaway of Brassica that raises an ...intriguing new aspect of plant signaling in which a receptor kinase may work with a nonreceptor kinase to activate the signal pathaway. Their examination shows that Murase et al's works present a new scenario in which receptor kinases cooperate with plasma membrane localized receptor-like cytoplasmic kinases and receptor-like kinases found in plant genomes. They stress that future studies will need to address the precise biochemical and cellular relationships among S receptor kinase, MLPK and ARCI in the plant self-incompatibility response.
We report on a 64-year old woman with an interstitial lung disease which had characteristics of hypersensitivity pneumonitis. Severe febrile attacks with impairment of ventilation and diffuse poorly ...defined radiodensities and ground glass opacities on chest x-ray occured repeatedly. Laboratory data showed hypoxemia, leukopenia and circulating Candida albicans (C.a.)-antigen. Bronchoalveolar lavage revealed an increase in neutrophils. Transbronchial biopsies showed lymphocytic alveolitis, bronchiolitis obliterans and epitheloid cell granulomas. IgG and IgA and the lymphocyte proliferation assay were positive with C.a.-antigen. C.a. was detected in the feces. Intradermal skin test with C.a. showed a positive immediate and late phase reaction and inhalative provocation test with C.a.-antigen was positive. After antimycotic treatment the symptoms resolved completely and long-lasting. We conclude that the disease was induced by C.a.-antigen reaching the lungs from the intestinal tract via the bloodstream.
In Deutschland genießt die Ideengeschichte ein so hohes Ansehen wie schon seit Langem nicht mehr. Mit der steigenden Popularität wird eine klärende Bestandsaufnahme des eigenen Methodenhaushaltes ...dringlich - ebenso steht eine Standortbestimmung innerhalb der Geschichtswissenschaft aus.Die Beiträger_innen des Bandes - darunter Quentin Skinner - untersuchen, an welche Traditionen die moderne ideengeschichtliche Forschung anknüpfen kann und welche bisher unerforschten Perspektiven sich ihr eröffnen.
Characteristics of turbulence structure in quasi-2D flows with static and weakly mobile gravel beds are presented. Three sets of measurements with acoustic Doppler velocimeters in an irrigation canal ...were used: two with subcritical bed shear stress (static beds) and one with the bed shear stress o close to critical oc (weakly mobile bed). The analyses included vertical distributions of local mean velocities, turbulence intensities, turbulent shear stresses, velocity auto- and cross-spectra, the quadrant method, and high-order velocity moments. A number of properties of turbulence intensities, high-order moments, streamwise bursting parameters, and velocity spectra appeared to be similar for all three flows, but some properties were different. The most important one was an observed reduction in the von Kármán constant for the flow with weakly mobile bed. Comparison of these results with other studies and analogies with drag-reducing flows suggest that at o oc 1 the drag on the bed for a given granular material should be minimized.
The 1–3cm thick near-bed layer at the interface between sea-water and the sea-bed was studied using two acoustic Doppler velocimeter (ADV) deployments in Beatrix Bay (New Zealand), which relate to ...late autumn and early winter conditions. The data strongly support the multi-mechanism nature of the near-bed layer and show that the turbulent stresses and energy may be non-zero even at nearly zero or zero mean velocities. The turbulent fluctuations in the near-bed layer are highly intermittent and consist of two components: (1) low energy ‘background’ fluctuations; and (2) relatively rare high-energy events (HEE). The structure, dynamics, and influence of these components on bed erosion, particle aggregation and re-suspension are significantly different. Our results suggest that the revealed high-energy events are the main contributors to bed erosion and sediment re-suspension. The estimates of the local Reynolds number and other turbulence parameters show that HEE may change the near-bed flow regime from viscous or transitional at low-energy background conditions to fully turbulent during the high-energy events. Although the physical origin of HEE is not yet clear, most probably they are generated by intermittent highly-energetic internal waves or near-bed convective mixing, or both. These results provide a base for future research in this complex near-bed region.
In Brassica species, self-incompatibility has been mapped genetically to a single chromosomal location. In this region, there are two closely linked genes coding for the S locus glycoprotein (SLG) ...and S locus receptor kinase (SRK). They appear to comprise the pistil component of the self-incompatibility reaction. SLG and SRK are thought to recognize an unknown pollen component on the incompatible pollen, and the gene encoding this pollen component must also be linked to the SLG and SRK genes. To further our understanding of self-incompatibility, the chromosomal region carrying the SLG and SRK genes has been studied. The physical region between the SLG-910 and the SRK-910 genes in the Brassica napus W1 line was cloned, and a search for genes expressed in the anther revealed two additional S locus genes located downstream of the SLG-910 gene. Because these two genes are novel and are conserved at other S alleles, we designated them as SLL1 and SLL2 (for S locus-linked genes 1 and 2, respectively). The SLL1 gene is S locus specific, whereas the SLL2 gene is not only present at the S locus but is also present in other parts of the genomes in both self-incompatible and self-compatible Brassica ssp lines. Expression of the SLL1 gene is only detectable in anthers of self-incompatible plants and is developmentally regulated during anther development, whereas the SLL2 gene is expressed in anthers and stigmas in both self-incompatible and self-compatible plants, with the highest levels of expression occurring in the stigmas. Although SLL1 and SLL2 are linked to the S locus region, it is not clear whether these genes function in self-incompatibility or serve some other cellular roles in pollen-pistil functions
The design of a straight benthic flow-through flume for in situ studies of cohesive sediment dynamics is described including the flume structure and probes installed for routine measurements of ...suspended sediments and flow velocity. The flume was calibrated for two roughness types covering the range of possible cohesive bed roughnesses. The calibration included a set of three-dimensional velocity measurements using acoustic Doppler velocimeter. These measurements were used to develop calibration relationships between the bed shear stress (which is difficult to measure directly in routine deployments) and the flume centerline flow velocity, which is routinely measured. An example of a successful deployment of the flume is presented. The limitations and potential for further improvements are also briefly discussed.
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