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Hillary A Hager Ryan J Roberts Emily E Cross Véronique Proux‐Gillardeaux David M Bader 《The EMBO journal》2010,29(3):532-545
Blood vessel/epicardial substance (Bves) is a transmembrane protein that influences cell adhesion and motility through unknown mechanisms. We have discovered that Bves directly interacts with VAMP3, a SNARE protein that facilitates vesicular transport and specifically recycles transferrin and β‐1‐integrin. Two independent assays document that cells expressing a mutated form of Bves are severely impaired in the recycling of these molecules, a phenotype consistent with disruption of VAMP3 function. Using Morpholino knockdown in Xenopus laevis, we demonstrate that elimination of Bves function specifically inhibits transferrin receptor recycling, and results in gastrulation defects previously reported with impaired integrin‐dependent cell movements. Kymographic analysis of Bves‐depleted primary and cultured cells reveals severe impairment of cell spreading and adhesion on fibronectin, indicative of disruption of integrin‐mediated adhesion. Taken together, these data demonstrate that Bves interacts with VAMP3 and facilitates receptor recycling both in vitro and during early development. Thus, this study establishes a newly identified role for Bves in vesicular transport and reveals a novel, broadly applied mechanism governing SNARE protein function. 相似文献
124.
Matthias Hofmann David Scheschkewitz Abolfazl Ghaffari Gertraud Geiseler Werner Massa Henry F. Schaefer III Armin Berndt 《Journal of molecular modeling》2000,6(2):257-271
Bishomotriborirane anions with a B-H-B bridge, 7, have been synthesized by a) protonation and b) methylation of bishomodianions, 3, as well as by c) hydride addition to 1,2,4-triboracyclopentanes, 15. Compounds 7 were characterized by 1H, 13C and 11B NMR spectroscopy and X-ray diffraction analyses. The suggested mechanism for the formation of 7 is supported by MP4SDTQ/6-311++G**//MP2(fc)/6-31+G* computations on [C2B3H8]- model compounds. Classical 1,2-dibora-4-borata-cyclopentane intermediates 16 undergo an intramolecular hydrogen shift to the B-B unit in their envelope conformation to give intermediates 17, which easily isomerize to 7. Relative energies for the parent compounds, 16u, 17u, 7u and the transition structures, TS-16/17u and TS-7/17u are predicted to be 30.7, 14.5, 0.0, 32.6 and 23.5 kcal mol-1, respectively. The terms classical and non-classical homobridges are suggested for methylene and hydrogen bridges in 7 and in related compounds on the grounds of common building principles. The strength of homoaromaticity in 7u was estimated to be at least 23.5 kcal mol-1, neglecting the much higher strain in 7u compared to TS-7/17u without a 3c2e bond.Electronic Supplementary Material available. 相似文献
125.
Grateful parents raising grateful children: Niche selection and the socialization of child gratitude
William A. Rothenberg Andrea M. Hussong Hillary A. Langley Gregory A. Egerton Amy G. Halberstadt Jennifer L. Coffman 《应用发育科学》2017,21(2):106-120
Given that children’s exposure to gratitude-related activities may be one way that parents can socialize gratitude in their children, we examined whether parents’ niche selection (i.e., tendency to choose perceived gratitude-inducing activities for their children) mediates the association between parents’ reports of their own and their children’s gratitude. Parent-child dyads (N = 101; children aged 6–9; 52% girls; 80% Caucasian; 85% mothers) participated in a laboratory visit and parents also completed a 7-day online diary regarding children’s gratitude. Decomposing specific indirect effects within a structural equation model, we found that parents high in gratitude were more likely to set goals to use niche selection as a gratitude socialization strategy, and thereby more likely to place their children in gratitude-related activities. Placement in these activities, in turn, was associated with more frequent expression of gratitude in children. We describe future directions for research on parents’ role in socializing gratitude in their children. 相似文献
126.
Brachiopodes de l'Ordovicien supérieur de Libye occidentale implications stratigraphiques régionales
This paper deals with fossiliferous shales and sandstones of Ordovician age from WesternLibya. Brachiopods indicate Caradocian and Ashgillian ages at least for part of the section. On ecological grounds it is possible to demonstrate the cold water character of faunal assemblages, related to a periglacial facies. Then this series is introduced on a broader scale into the Cambro-Ordovician of Libya. Good correlations are established between Libya, Morocco and South-Africa, thus offering, through faunal control alone, a striking view of the huge size of glacial phenomena during Upper-Ordovician. 相似文献
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E Rabino Massa G Ricco C Polimeni M Reddavid 《Bollettino della Società italiana di biologia sperimentale》1992,68(3):167-174
The authors report that a diluted solution of Hb-Kempsey, beta 99 (G-1) Asp-Asn, can be chromatographically separated from the coexistent Hb-A and functionally examined if progressively depleted in O2 by bubbling pure nitrogen in the solution. Next, at fixed times, the O2 saturations of Hb are compared with the pO2s measured. Hb-Kempsey has a p50 of 1 torr, with an n-value of 1 and a Bohr effect of -0.2. Normal Hb-A of the same patient, examined with identical methods, presents: p50 = 4.5 torr; n = 2.7; Bohr effect = -0.412. Therefore, Hb-Kempsey is strongly hyperaffinic, does not display any heme-heme interaction, and has a half-normal Bohr effect. 相似文献
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Monory K Blaudzun H Massa F Kaiser N Lemberger T Schütz G Wotjak CT Lutz B Marsicano G 《PLoS biology》2007,5(10):e269
Marijuana and its main psychotropic ingredient Delta(9)-tetrahydrocannabinol (THC) exert a plethora of psychoactive effects through the activation of the neuronal cannabinoid receptor type 1 (CB1), which is expressed by different neuronal subpopulations in the central nervous system. The exact neuroanatomical substrates underlying each effect of THC are, however, not known. We tested locomotor, hypothermic, analgesic, and cataleptic effects of THC in conditional knockout mouse lines, which lack the expression of CB1 in different neuronal subpopulations, including principal brain neurons, GABAergic neurons (those that release gamma aminobutyric acid), cortical glutamatergic neurons, and neurons expressing the dopamine receptor D1, respectively. Surprisingly, mice lacking CB1 in GABAergic neurons responded to THC similarly as wild-type littermates did, whereas deletion of the receptor in all principal neurons abolished or strongly reduced the behavioural and autonomic responses to the drug. Moreover, locomotor and hypothermic effects of THC depend on cortical glutamatergic neurons, whereas the deletion of CB1 from the majority of striatal neurons and a subpopulation of cortical glutamatergic neurons blocked the cataleptic effect of the drug. These data show that several important pharmacological actions of THC do not depend on functional expression of CB1 on GABAergic interneurons, but on other neuronal populations, and pave the way to a refined interpretation of the pharmacological effects of cannabinoids on neuronal functions. 相似文献