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91.
Human sprouty 4, a new ras antagonist on 5q31, interacts with the dual specificity kinase TESK1. 总被引:2,自引:0,他引:2
Onno C Leeksma Tanja A E Van Achterberg Yoshikazu Tsumura Jiro Toshima Eric Eldering Wilma G M Kroes Clemens Mellink Marcel Spaargaren Kensaku Mizuno Hans Pannekoek Carlie J M de Vries 《European journal of biochemistry》2002,269(10):2546-2556
The Drosophila melanogaster protein sprouty is induced upon fibroblast growth factor (FGF)- and epidermal growth factor (EGF)-receptor tyrosine kinase activation and acts as an inhibitor of the ras/MAP kinase pathway downstream of these receptors. By differential display RT-PCR of activated vs. resting umbilical artery smooth muscle cells (SMCs) we detected a new human sprouty gene, which we designated human sprouty 4 (hspry4) based on its homology with murine sprouty 4. Hspry4 is widely expressed and Northern blots indicate that different isoforms of hspry4 are induced upon cellular activation. The hspry4 gene maps to 5q31.3. It encodes a protein of 322 amino acids, which, in support of a modulating role in signal transduction, contains a prototypic cysteine-rich region, three, potentially Src homology 3 (SH3) binding, proline-rich regions and a PEST sequence. This new sprouty orthologue can suppress the insulin- and EGF-receptor transduced MAP kinase signaling pathway, but fails to inhibit MAP kinase activation by constitutively active V12 ras. Hspry4 appears to impair the formation of active GTP-ras and exert its activity at the level of wild-type ras or upstream thereof. In a yeast two-hybrid screen, using hspry4 as bait, testicular protein kinase 1 (TESK1) was identified from a human fetal liver cDNA library as a partner of hspry4. The hspry4-TESK1 interaction was confirmed by coimmunoprecipitation experiments and increases by growth factor stimulation. The two proteins colocalize in apparent cytoplasmic vesicles and do not show substantial translocation to the plasma membrane upon receptor tyrosine kinase stimulation. 相似文献
92.
Díaz López E A Morales Ruíz EJ Vargas Ramírez P Hernández Herrera RC Reséndiz Melgar I Brena Hernández JM Loeza Corte 《Phyton》2015,84(2):319-330
The effect of six phosphorus levels (0, 40, 80, 120, 160 and 200 kg/ha) on the duration of cumulative leaf area, biomass and agronomic yield was determined in the maize cultivars: Amarillo Almoloya, Cacahuacintle and Condor in 2010 and 2011. Such cultivars were sown in the Cerrillo Piedras Blancas Mexico. A completely randomized complete block design with factorial arrangement was utilized. High phosphorus levels (120, 160 and 200 kg/ha) positively affected the duration of cumulative leaf area; greatest values were obtained in Cacahuacintle. A greater duration of accumulated leaf area contributes to determine high values of biomass accumulation and grain yield in this cultivar. Leaf area duration appeared to be a useful tool for evaluating different genotypes in a given environment. 相似文献
93.
The subfamily Microtypinae Szépligeti, 1908 (Hymenoptera: Braconidae) is recorded for the first time for Egypt. The present study is based on specimens collected from Gebel Elba, Wadi Allaqi, St. Catherine, and Fayoum, as well as specimens deposited in various entomological collections in Egypt. Four species belonging to the genus Microtypus Ratzeburg, 1848 (M. algiricus Szépligeti, 1908; M. desertorum Shestakov, 1932; M. vanharteni van Achterberg, 2010 and M. aegypticus sp. n.) are reported for the first time from Egypt.http://www.zoobank.org/urn:lsid:zoobank.org:pub:022282A1-183F-4E0C-9F88-A53C42735532 相似文献
94.
Dexamethasone induces gelsolin synthesis and altered morphology in L929 cells 总被引:1,自引:1,他引:0 下载免费PDF全文
When L929 cells are exposed to 5 μg/ml dexamethasone, synthesis of a 90,000 M(r) polypeptide is induced within 12 h. Flattening of the cells begins at about this time and progresses to become quite prominent after 48 h of exposure. Two-dimensional PAGE and partial proteolytic fingerprints identify the 90,000 M(r) polypeptide as gelsolin, a Ca(++)-dependent inhibitor of actin polymerization. Thus, this system provides evidence that gelsolin may have a role in regulating cell shape in response to physiological agents such as glucocorticoids. 相似文献
95.
Stefan Richter Rudi Loesel Günter Purschke Andreas Schmidt-Rhaesa Gerhard Scholtz Thomas Stach Lars Vogt Andreas Wanninger Georg Brenneis Carmen Döring Simone Faller Martin Fritsch Peter Grobe Carsten M Heuer Sabrina Kaul Ole S Møller Carsten HG Müller Verena Rieger Birgen H Rothe Martin EJ Stegner Steffen Harzsch 《Frontiers in zoology》2010,7(1):1-49
96.
97.
Vladimir ?iki? Cees van Achterberg Saša S. Stankovi?Marijana Ili? 《Zoologischer Anzeiger》2011,250(3):246-257
The morphology of the male genitalia of 46 Agathidinae species belonging to 20 genera has been investigated. Samples from various geographical regions were used to discover the evolution of the male genitalia within the subfamily Agathidinae. Those male genitalia may contain important phylogenetic information at least in certain groups of Braconidae. For the New World, three of four investigated species of Cremnops (C. haematodes, C. montrealensis and C. vulgaris) could suggest the form of the new genus with the other members of New World Cremnops, partly because of the deviating morphology of the male genitalia. Comparative morphology of the male genitalia of Bassus confirms that it is polyphyletic. The status of Lytopylus (L. erythrogaster) is again actualised. Once synonymised as Aerophilopsis, this species could be excluded from other Lytopylus species. The statistical analysis showed that smaller specimens (<6.67 mm) give less details on the morphology of the male genitalia comparing to larger. 相似文献
98.
Background
We consider the potential for infection to spread in a farm population from the primary outbreak farm via livestock movements prior to disease detection. We analyse how this depends on the time of the year infection occurs, the species transmitting, the length of infectious period on the primary outbreak farm, location of the primary outbreak, and whether a livestock market becomes involved. We consider short infectious periods of 1 week, 2 weeks and 4 weeks, characteristic of acute contagious livestock diseases. The analysis is based on farms in Scotland from 1 January 2003 to 31 July 2007.Results
The proportion of primary outbreaks from which an acute contagious disease would spread via movement of livestock is generally low, but exhibits distinct annual cyclicity with peaks in May and August. The distance that livestock are moved varies similarly: at the time of the year when the potential for spread via movements is highest, the geographical spread via movements is largest. The seasonal patterns for cattle differ from those for sheep whilst there is no obvious seasonality for pigs. When spread via movements does occur, there is a high risk of infection reaching a livestock market; infection of markets can amplify disease spread. The proportion of primary outbreaks that would spread infection via livestock movements varies significantly between geographical regions.Conclusions
In this paper we introduce a set-up for analysis of movement data that allows for a generalized assessment of the risk associated with infection spreading from a primary outbreak farm via livestock movements, applying this to Scotland, we assess how this risk depends upon the time of the year, species transmitting, location of the farm and other factors. 相似文献99.
A sample of fixed bacterial cells was examined by immunofluorescence microscopy using an Alexa 488 conjugated secondary antibody for visualization. Excitation using visible light confirmed the expected photostability of this fluorophore; however, when using 2-photon excitation, Alexa 488 was rapidly and substantially photobleached. The unexpected instability of Alexa 488 under certain conditions may have deleterious consequences if not anticipated and accommodated in experimental protocols. 相似文献
100.
Johan P. de Winter Carlie J.M. de Vries Tanja A.E. van Achterberg Robert F. Ameerun Alie Feijen Hiromu Sugino Peter de Waele Danny Huylebroeck Kristin Verschueren Adriana J.M. van den Eijnden-van Raaij 《Experimental cell research》1996,224(2):323
Truncated activin type II receptors have been reported to inhibit activin receptor signaling inXenopusembryos, although the mechanism of action for this effect has not been fully understood. In the present study we demonstrate that in P19 embryonal carcinoma cells both the induction of the activin responsive 3TP-lux reporter construct and the inhibition of retinoic acid-induced neuronal differentiation by activin are blocked by expression of a truncated activin receptor. To reveal the mechanism of action of truncated activin receptors, the interaction between different activin receptors has been investigated upon coexpression in COS cells followed by cross-linking of125I-activin A and subsequent immunoprecipitation. Complexes between a truncated activin type IIA receptor and activin type IA and type IB receptors can be formed, as demonstrated by coimmunoprecipitation of these type I receptors with the truncated activin type IIA receptor. Other type I receptors known as ALK-1 and ALK-6 also coimmunoprecipitate with the truncated type IIA receptor, whereas ALK-3 and ALK-5 do not. Furthermore, the activin type IIB2receptor does not coimmunoprecipitate with the truncated type IIA receptor, but decreases activin binding to the truncated type IIA receptor. In double immunoprecipitation experiments with cell lysates from COS cells, in which full-length activin type IIA and type IIB2receptors were cotransfected, no interaction between these receptors was found. In contrast, homomeric complexes of full-length activin type IIA receptors were detected. These results implicate that truncated activin receptors can interfere with activin signaling by interacting with activin type I receptors. Additionally, truncated activin type IIB2receptors might also interfere with type IIA receptor signaling by decreasing activin binding to the type IIA receptor and therefore might be more potent in inhibiting activin signal transduction. Furthermore, our data indicate that truncated type IIA receptors can interact with other type I receptors and as such might inhibit signal transduction by type I receptors other than activin type IA and type IB receptors. 相似文献