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91.
Destaing O Planus E Bouvard D Oddou C Badowski C Bossy V Raducanu A Fourcade B Albiges-Rizo C Block MR 《Molecular biology of the cell》2010,21(23):4108-4119
Invadosomes are adhesion structures involved in tissue invasion that are characterized by an intense actin polymerization–depolymerization associated with β1 and β3 integrins and coupled to extracellular matrix (ECM) degradation activity. We induced the formation of invadosomes by expressing the constitutive active form of Src, SrcYF, in different cell types. Use of ECM surfaces micropatterned at the subcellular scale clearly showed that in mesenchymal cells, integrin signaling controls invadosome activity. Using β1−/− or β3−/− cells, it seemed that β1A but not β3 integrins are essential for initiation of invadosome formation. Protein kinase C activity was shown to regulate autoassembly of invadosomes into a ring-like metastructure (rosette), probably by phosphorylation of Ser785 on the β1A tail. Moreover, our study clearly showed that β1A links actin dynamics and ECM degradation in invadosomes. Finally, a new strategy based on fusion of the photosensitizer KillerRed to the β1A cytoplasmic domain allowed specific and immediate loss of function of β1A, resulting in disorganization and disassembly of invadosomes and formation of focal adhesions. 相似文献
92.
93.
Supaporn Hasthanasombut Valentine Ntui Kanyaratt Supaibulwatana Masahiro Mii Ikuo Nakamura 《Plant biotechnology reports》2010,4(1):75-83
Glycine betaine has been reported as an osmoprotectant compound conferring tolerance to salinity and osmotic stresses in plants.
We previously found that the expression of betaine aldehyde dehydrogenase 1 gene (OsBADH1), encoding a key enzyme for glycine betaine biosynthesis pathway, showed close correlation with salt tolerance of rice. In
this study, the expression of the OsBADH1 gene in transgenic tobacco was investigated in response to salt stress using a transgenic approach. Transgenic tobacco plants
expressing the OsBADH1 gene were generated under the control of a promoter from the maize ubiquitin gene. Three homozygous lines of T2 progenies with single transgene insert were chosen for gene expression analysis. RT-PCR and western blot analysis results
indicated that the OsBADH1 gene was effectively expressed in transgenic tobacco leading to the accumulation of glycine betaine. Transgenic lines demonstrated
normal seed germination and morphology, and normal growth rates of seedlings under salt stress conditions. These results suggest
that the OsBADH1 gene could be an excellent candidate for producing plants with osmotic stress tolerance. 相似文献
94.
Kendall MM Wardlaw GD Tang CF Bonin AS Liu Y Valentine DL 《Applied and environmental microbiology》2007,73(2):407-414
Methanogenesis in cold marine sediments is a globally important process leading to methane hydrate deposits, cold seeps, physical instability of sediment, and atmospheric methane emissions. We employed a multidisciplinary approach that combined culture-dependent and -independent analyses with geochemical measurements in the sediments of Skan Bay, Alaska (53 degrees N, 167 degrees W), to investigate methanogenesis there. Cultivation-independent analyses of the archaeal community revealed that uncultivated microbes of the kingdoms Euryarchaeota and Crenarchaeota are present at Skan Bay and that methanogens constituted a small proportion of the archaeal community. Methanogens were cultivated from depths of 0 to 60 cm in the sediments, and several strains related to the orders Methanomicrobiales and Methanosarcinales were isolated. Isolates were psychrotolerant marine-adapted strains and included an aceticlastic methanogen, strain AK-6, as well as three strains of CO(2)-reducing methanogens: AK-3, AK7, and AK-8. The phylogenetic positions and physiological characteristics of these strains are described. We propose a new species, Methanogenium boonei, with strain AK-7 as the type strain. 相似文献
95.
96.
Franciskovich JB Masters JJ Weber WW Klimkowski VJ Chouinard M Sipes PR Johnson LM Snyder DW Chastain MK Craft TJ Towner RD Gifford-Moore DS Froelich LL Smallwood JK Foster RS Smith GF Liebeschuetz JW Murray CW Young SC 《Bioorganic & medicinal chemistry letters》2007,17(24):6910-6913
Several P4 domain derivatives of the general d-phenylglycinamide-based scaffold (2) were synthesized and evaluated for their ability to bind to the serine protease factor Xa. Some of the more potent compounds were evaluated for their anticoagulant effects in vitro. A select subset containing various P1 indole constructs was further evaluated for their pharmacokinetic properties after oral administration to rats. 相似文献
97.
Hay BA Abrams B Zumbrunn AY Valentine JJ Warren LC Petras SF Shelly LD Xia A Varghese AH Hawkins JL Van Camp JA Robbins MD Landschulz K Harwood HJ 《Bioorganic & medicinal chemistry letters》2007,17(16):4411-4414
The discovery and efficacy of a series of potent aminopyrrolidineamide-based inhibitors of sterol regulatory element binding protein site-1 protease is described. 相似文献
98.
More than 100 different mutations in the gene encoding copper-zinc superoxide dismutase (SOD1) cause familial forms of amyotrophic lateral sclerosis (ALS)--a fatal neurodegenerative disease in which aggregation of the SOD1 protein is considered to be the primary mode of pathogenesis. Recent results show that these mutations have remarkably diverse and unexpected effects on the structure, activity and native state stability of SOD1. Intriguingly, many mutations seem to have no measurable effect on the biophysical and biochemical properties of SOD1, except for decreasing the net charge of the protein. Thus, it seems likely that different ALS-associated mutations promote SOD1 aggregation by fundamentally distinct mechanisms. Understanding this complexity has implications for drug development and treatment of the disease. 相似文献
99.
100.
Nucci NV Marques BS Bédard S Dogan J Gledhill JM Moorman VR Peterson RW Valentine KG Wand AL Wand AJ 《Journal of biomolecular NMR》2011,50(4):421-430
Comprehensive application of solution NMR spectroscopy to studies of macromolecules remains fundamentally limited by the molecular
rotational correlation time. For proteins, molecules larger than 30 kDa require complex experimental methods, such as TROSY
in conjunction with isotopic labeling schemes that are often expensive and generally reduce the potential information available.
We have developed the reverse micelle encapsulation strategy as an alternative approach. Encapsulation of proteins within
the protective nano-scale water pool of a reverse micelle dissolved in ultra-low viscosity nonpolar solvents overcomes the
slow tumbling problem presented by large proteins. Here, we characterize the contributions from the various components of
the protein-containing reverse micelle system to the rotational correlation time of the encapsulated protein. Importantly,
we demonstrate that the protein encapsulated in the reverse micelle maintains a hydration shell comparable in size to that
seen in bulk solution. Using moderate pressures, encapsulation in ultra-low viscosity propane or ethane can be used to magnify
this advantage. We show that encapsulation in liquid ethane can be used to reduce the tumbling time of the 43 kDa maltose
binding protein from ~23 to ~10 ns. These conditions enable, for example, acquisition of TOCSY-type data resolved on the adjacent
amide NH for the 43 kDa encapsulated maltose binding protein dissolved in liquid ethane, which is typically impossible for
proteins of such size without use of extensive deuteration or the TROSY effect. 相似文献