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141.
Promoting extracellular matrix remodeling via ascorbic acid enhances the survival of primary ovarian follicles encapsulated in alginate hydrogels
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142.
Juan F. Abenza Antonio Galindo Areti Pantazopoulou Concha Gil Vivian de los Ríos Miguel A. Pe?alva 《Molecular biology of the cell》2010,21(15):2756-2769
Aspergillus nidulans early endosomes display characteristic long-distance bidirectional motility. Simultaneous dual-channel acquisition showed that the two Rab5 paralogues RabB and RabA colocalize in these early endosomes and also in larger, immotile mature endosomes. However, RabB-GTP is the sole recruiter to endosomes of Vps34 PI3K (phosphatidylinositol-3-kinase) and the phosphatidylinositol-3-phosphate [PI(3)P] effector AnVps19 and rabBΔ, leading to thermosensitivity prevents multivesicular body sorting of endocytic cargo. Thus, RabB is the sole mediator of degradative endosomal identity. Importantly, rabBΔ, unlike rabAΔ, prevents early endosome movement. As affinity experiments and pulldowns showed that RabB-GTP recruits AnVps45, RabB coordinates PI(3)P-dependent endosome-to-vacuole traffic with incoming traffic from the Golgi and with long-distance endosomal motility. However, the finding that Anvps45Δ, unlike rabBΔ, severely impairs growth indicates that AnVps45 plays RabB-independent functions. Affinity chromatography showed that the CORVET complex is a RabB and, to a lesser extent, a RabA effector, in agreement with GST pulldown assays of AnVps8. rabBΔ leads to smaller vacuoles, suggesting that it impairs homotypic vacuolar fusion, which would agree with the sequential maturation of endosomal CORVET into HOPS proposed for Saccharomyces cerevisiae. rabBΔ and rabAΔ mutations are synthetically lethal, demonstrating that Rab5-mediated establishment of endosomal identity is essential for A. nidulans. 相似文献
143.
144.
Ngo Thi Hai Yen Xenia Bogdanović Gottfried J. Palm Olaf Kühl Winfried Hinrichs 《Journal of biological inorganic chemistry》2010,15(2):195-201
Crystal structures of polypeptide deformylase (PDF) of Escherichia coli with nickel(II) replacing the native iron(II) have been solved with chloride and formate as metal ligands. The chloro complex
is a model for the correct protonation state of the hydrolytic hydroxo ligand and the protonated status of the Glu133 side
chain as part of the hydrolytic mechanism. The ambiguity that recently some PDFs have been identified with Zn2+ ion as the active-site centre whereas others are only active with Fe2+ (or Co2+, Ni2+) is discussed with respect to Lewis acid criteria of the metal ion and substrate activation by the CD loop. 相似文献
145.
Maurice O. Ouko Adrian Sambade Katrin Brandner Annette Niehl Eduardo Peña Abdul Ahad Manfred Heinlein Peter Nick 《The Plant journal : for cell and molecular biology》2010,62(5):829-839
A panel of seven SR1 tobacco mutants (ATER1 to ATER7) derived via T‐DNA activation tagging and screening for resistance to a microtubule assembly inhibitor, ethyl phenyl carbamate, were used to study the role of microtubules during infection and spread of tobacco mosaic virus (TMV). In one of these lines, ATER2, α‐tubulin is shifted from the tyrosinylated into the detyrosinated form, and the microtubule plus‐end marker GFP–EB1 moves significantly slower when expressed in the background of the ATER2 mutant as compared with the SR1 wild type. The efficiency of cell‐to‐cell movement of TMV encoding GFP‐tagged movement protein (MP‐GFP) is reduced in ATER2 accompanied by a reduced association of MP‐GFP with plasmodesmata. This mutant is also more tolerant to viral infection as compared with the SR1 wild type, implying that reduced microtubule dynamics confer a comparative advantage in face of TMV infection. 相似文献
146.
Estefania Peña B. Calvo M. A. Martínez P. Martins T. Mascarenhas R. M. N. Jorge A. Ferreira M. Doblaré 《Biomechanics and modeling in mechanobiology》2010,9(1):35-44
In this paper, the viscoelastic mechanical properties of vaginal tissue are investigated. Using previous results of the authors
on the mechanical properties of biological soft tissues and newly experimental data from uniaxial tension tests, a new model
for the viscoelastic mechanical properties of the human vaginal tissue is proposed. The structural model seems to be sufficiently
accurate to guarantee its application to prediction of reliable stress distributions, and is suitable for finite element computations.
The obtained results may be helpful in the design of surgical procedures with autologous tissue or prostheses. 相似文献
147.
Different methods to estimate the plasma membrane potential difference (PMP) of yeast cells with fluorescent monitors were
compared. The validity of the methods was tested by the fluorescence difference with or without glucose, and its decrease
by the addition of 10 mM KCl. Low CaCl2 concentrations avoid binding of the dye to the cell surface, and low CCCP concentrations avoid its accumulation by mitochondria.
Lower concentrations of Ba2+ produce a similar effect as Ca2+, without producing the fluorescence changes derived from its transport. Fluorescence changes without considering binding
of the dyes to the cells and accumulation by mitochondria are overshadowed by their distribution between this organelle and
the cytoplasm. Other factors, such as yeast starvation, dye used, parameters of the fluorescence changes, as well as buffers
and incubation times were analyzed. An additional approach to measure the actual or relative values of PMP, determining the
accumulation of the dye, is presented. 相似文献
148.
Allothrombium clavatum sp. n. with reduced inner claw of tarus III, one seta on coxa II, clavate dorsal idiosomal setae and 3-lobed posterior margin
of scutum, collected as ectoparasite of an undetermined aphid, is described and illustrated from the central part of Montenegro
(Balkan Peninsula). A key to world species of Allothrombium (larva) is presented. 相似文献
149.
Claudia A d'Alençon Oscar A Peña Christine Wittmann Viviana E Gallardo Rebecca A Jones Felix Loosli Urban Liebel Clemens Grabher Miguel L Allende 《BMC biology》2010,8(1):151
Background
Studies on innate immunity have benefited from the introduction of zebrafish as a model system. Transgenic fish expressing fluorescent proteins in leukocyte populations allow direct, quantitative visualization of an inflammatory response in vivo. It has been proposed that this animal model can be used for high-throughput screens aimed at the identification of novel immunomodulatory lead compounds. However, current assays require invasive manipulation of fish individually, thus preventing high-content screening. 相似文献150.
Henry F. Howe Yuliana Urincho-Pantaleon Marinés de la Peña-Domene Cristina Martínez-Garza 《Oecologia》2010,164(3):731-740
We explore processes of seed immigration and seedling recruitment before an experimental rainforest restoration matures enough
to affect either. Twenty-four 30 × 30-m plots were fenced in 12 ha of pasture in 2006. Seeds were collected in ninety-six
1-m−2 seed traps; recruits were censused in ~12,000 m2 in which establishment was allowed. We tested effects of distance from forest, living trees, and stumps of trees cut during
site preparation on seed rain in 2007 and effects of these and soil depth on recruits through June 2008. Seed fall and recruitment
were not correlated with distance to forest 90–400 m away, nor to living shade trees outside the 160 × 485-m experimental
grid. Recruitment differed for animal- and wind-dispersed species in a topographically complex landscape. Recruitment of wind-dispersed
species was random with respect to soil depth or distance to recent stumps. Recruitment of animal-dispersed species was multimodal;
partial correlations with number of stumps within 30 m of plots were significant with soil depth held constant (P < 0.025), as were correlations of recruitment with soil depth with number of stumps held constant (P < 0.01). Animal-dispersed recruits were often not conspecifics of adults that had been cut, indicating a legacy of attraction
by fruiting trees of animals bearing seeds from distant sources. Ecological implications are that recruitment in pastures
released from grazing reflects a mix of widely scattered wind-dispersed pioneers and, where animal-dispersed trees exist,
multi-modal and decidedly non-random recruitment of pioneer and later successional animal-dispersed trees from seed banks. 相似文献