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排序方式: 共有360条查询结果,搜索用时 21 毫秒
21.
Membrane nanotubes are a morphologically versatile group of membrane structures (some resembling filopodia), usually connecting two closely positioned cells. In this article, we set morphological criteria that distinguish the membrane nanotubes from filopodia, as there is no specific molecular marker known to date that unequivocally differentiates between filopodia and protruding nanotubes. Membrane nanotubes have been extensively studied from the morphological point of view and the transport that can be conducted through them, but little is known about the way they connect to the adjacent cell. Our results show that the nanotubes may connect to a neighboring cell by anchoring junctions. Among cell adhesion proteins, N-cadherin, β-catenin, nectin-2, afadin and the desmosomal protein desmoplakin-2 were immune-labeled. We found that N-cadherin and β-catenin are concentrated in nanotubes, while the concentrations of other junction-involved proteins are not increased in these structures. On the basis of data from transmission electron microscopy, we propose a model of the nanotube attachment where the connection of nanotubes is stabilized by several anchoring junctions, most likely adherens junctions that are formed when the nanotube is sliding along the target cell membrane. 相似文献
22.
The phylogenetic status of brown trout Salmo trutta L 1758 in Sicily is uncertain as some reports describe these trout as S. macrostigma or S. cettii on one hand while other, contradictory reports imply a hatchery origin on the other. In order to clarify this situation,
we performed sequence analysis of the mtDNA control region and restriction fragment analysis of the nuclear lactate dehydrogenase
(LDH-C1*) gene. A single mitochondrial haplotype (At-s6) found previously in brown trout in Morocco, and two alleles at LDH-C1* (the ancestral*100, at a high frequency, and *90) were revealed. Our results suggest that Sicilian brown trout are native and that they probably colonized Sicily from west
to east in an expansion, from the Atlantic Ocean basin, along the North-West African coast.
Handling editor: C. Sturmbauer 相似文献
23.
Akrong M. O. Anning A. K. Addico G. N. D. Hogarh J. N. Adu-Gyamfi A. deGraft-Johnson K. A. A. Ale M. Meyer A. S. 《Journal of applied phycology》2022,34(5):2589-2601
Journal of Applied Phycology - Seaweed abundance and polysaccharide properties can vary spatially and temporarily, influenced by various environmental factors, although information on this is... 相似文献
24.
Kejík Z Bříza T Králová J Poučková P Král A Martásek P Král V 《Bioorganic & medicinal chemistry letters》2011,21(18):5514-5520
We present here a general system for the coordination attachment of therapeutic proteins to a drug delivery system and its application in combined therapy. Proof of concept is demonstrated by the synthesis and testing of the targeted drug delivery system for cytostatics, which is based on a combination of the drug carrier Zn-porphyrin-cyclodextrin conjugates and their supramolecular coordination complexes with immunoglobulins. This system can be as readily used for a variety of therapeutic and targeting proteins including PAs, MAs, lectins, and HSA. Moreover, it allows combined photodynamic therapy, cell targeted chemotherapy and immunotherapy. When tested in a mouse model with human C32 carcinoma, the therapeutic superiority of the coordination assembly nanosystem was shown in comparison with the efficacy of building blocks used for the construction of the system. 相似文献
25.
Inhibition of SAH-hydrolase activity during seed germination leads to deregulation of flowering genes and altered flower morphology in tobacco 总被引:1,自引:0,他引:1
Fulneček J Matyášek R Votruba I Holý A Křížová K Kovařík A 《Molecular genetics and genomics : MGG》2011,285(3):225-236
Developmental processes are closely connected to certain states of epigenetic information which, among others, rely on methylation
of chromatin. S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) are key cofactors of enzymes catalyzing DNA and histone methylation. To study the consequences
of altered SAH/SAM levels on plant development we applied 9-(S)-(2,3-dihydroxypropyl)-adenine (DHPA), an inhibitor of SAH-hydrolase, on tobacco seeds during a short phase of germination
period (6 days). The transient drug treatment induced: (1) dosage-dependent global DNA hypomethylation mitotically transmitted
to adult plants; (2) pleiotropic developmental defects including decreased apical dominance, altered leaf and flower symmetry,
flower whorl malformations and reduced fertility; (3) dramatic upregulation of floral organ identity genes NTDEF, NTGLO and NAG1 in leaves. We conclude that temporal SAH-hydrolase inhibition deregulated floral genes expression probably via chromatin
methylation changes. The data further show that plants might be particularly sensitive to accurate setting of SAH/SAM levels
during critical developmental periods. 相似文献
26.
Kralj-Iglic V Hägerstrand H Veranic P Jezernik K Babnik B Gauger DR Iglic A 《European biophysics journal : EBJ》2005,34(8):1066-1070
Amphiphile-induced tubular budding of the erythrocyte membrane was studied using transmission electron microscopy. No chiral patterns of the intramembraneous particles were found, either on the cylindrical buds, or on the tubular nanoexovesicles. In agreement with these observations, the tubular budding may be explained by in-plane ordering of anisotropic membrane inclusions in the buds where the difference between the principal membrane curvatures is very large. In contrast to previously reported theories, no direct external mechanical force is needed to explain tubular budding of the bilayer membrane. 相似文献
27.
28.
Biserka Bakra? Ale? Kladnik Peter Ma?ek Gavin McHaffie Andreas Werner Jeremy H. Lakey Gregor Anderluh 《The Journal of biological chemistry》2010,285(29):22186-22195
Although sphingomyelin is an important cellular lipid, its subcellular distribution is not precisely known. Here we use a sea anemone cytolysin, equinatoxin II (EqtII), which specifically binds sphingomyelin, as a new marker to detect cellular sphingomyelin. A purified fusion protein composed of EqtII and green fluorescent protein (EqtII-GFP) binds to the SM rich apical membrane of Madin-Darby canine kidney (MDCK) II cells when added exogenously, but not to the SM-free basolateral membrane. When expressed intracellularly within MDCK II cells, EqtII-GFP colocalizes with markers for Golgi apparatus and not with those for nucleus, mitochondria, endoplasmic reticulum or plasma membrane. Colocalization with the Golgi apparatus was confirmed by also using NIH 3T3 fibroblasts. Moreover, EqtII-GFP was enriched in cis-Golgi compartments isolated by gradient ultracentrifugation. The data reveal that EqtII-GFP is a sensitive probe for membrane sphingomyelin, which provides new information on cytosolic exposure, essential to understand its diverse physiological roles. 相似文献
29.
30.
Spirichev VB Donchenko GV Blazheevich NV Parkhomenko IuM Aleĭnik SI Golubkina NA Vrzhesinskaia OA Isaeva VA Kodentsova VM Pereverzeva OG Sokol'nikov AE Iakushina LM 《Ukrainski? biokhimicheski? zhurnal》2006,78(2):5-26
Results of the study of the provision with vitamins and some micro- and macroelements of limited groups of people, who suffered from the accident at the Chornobyl nuclear power plant (ChNPP), which have been carried out by Ukrainian and Russian scientists during various periods after the accident, are generalized in the paper. Persons which participated in liquidation of the accident and lived during the accident in the territory, adjoining to Pripyat (the Kyiv region, town of Slavutich), people which worked at the object "Shelter" and ChNPP were involved in the inspection. It was noted, that in 1-4 years after the ChNPP accident in blood of liquidators the biochemical parameters displaying security of their organism by vitamins A and B1, remain lower in comparison with the same parameters in a group of relatively healthy persons which were not affected by the accident (control), that testifies to stable metabolic disturbance in the organism of people under irradiation influence. Selective inspection of the vitamin status of ChNPP and object "Shelter" personnel in 1992 has shown, that provision with vitamins C, B1, B2, B6 of the overwhelming majority of these people (67-91%) are much below the norm. Deficiency of vitamins C, B1, B6, folate and selenium is also revealed in an organism of 50-90% of women and children living in Slavutich. Deficit of vitamins in most of persons was characterized by polyhypovitaminoses, that is a combination of several group B vitamins deficiency at simultaneously low provision with selenium, and in a part of women and children--by low amount of iron. The results of long-term complex studies by groups of authors give evidence on importance and urgency of formulation and execution of International program on optimisation of nutrition, micronutrition status and health among population of affected areas in Ukraine, Bielorus' and Russia. 相似文献