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51.
Marina S. Trofimova Inna M. Zhestkova Valentina P. Kholodova Igor M. Andreev Evgeny M. Sorokin Anna G. Kruglova Vladimir V. Kuznetsov 《Physiologia plantarum》2003,118(2):232-239
The osmotic water permeability ( P os ) of cell membranes isolated from leaves of 40-, 50- and 60-day-old Mesembryanthemum crystallinum plants was estimated by measuring light-scattering kinetics using stopped-flow spectrophotometry. The measurements were performed on the plasma membrane (PM), purified tonoplast (TP), and TP-enriched vesicles. The PM and TP-enriched vesicles were obtained by partitioning the microsomal fraction in an aqueous polymer two-phase system, whereas the purified TP vesicles were prepared by microsomal vesicle flotation on a sucrose cushion. The P os of isolated membranes declined with plant age. The kinetic experiments showed that there was no difference between the P os of the PM and TP isolated from plants of all ages. A 24-h exposure of plants to 400 m M NaCl caused a decline in the P os as well. These findings suggest that, during M. crystallinum transition to CAM, which was induced by plant ageing or salinity, plant osmoregulatory responses included changes in the P os of the leaf-cell membranes. These variations in the P os are discussed in the context of adaptive mechanisms responsible for the maintenance of the water balance in the common ice plant. 相似文献
52.
Decreased rates of cerebral protein synthesis measured in vivo in a mouse model of Tuberous Sclerosis Complex: unexpected consequences of reduced tuberin 下载免费PDF全文
Rachel Michelle Saré Tianjian Huang Tom Burlin Inna Loutaev Carolyn Beebe Smith 《Journal of neurochemistry》2018,145(5):417-425
53.
The nervous system of Tricladida. II. Neuroanatomy ofDugesia tigrina (Paludicola,Dugesiidae): An immunocytochemical study 总被引:2,自引:0,他引:2
54.
Alpeeva IS Niculescu-Nistor M Leon JC Csöregi E Sakharov IY 《Biosensors & bioelectronics》2005,21(5):742-748
Three amperometric enzyme electrodes have been constructed by adsorbing anionic royal palm tree peroxidase (RPTP), anionic sweet potato peroxidase (SPP), or cationic horseradish peroxidase (HRP-C) on spectroscopic graphite electrodes. The resulting H(2)O(2)-sensitive biosensors were characterized both in a flow injection system and in batch mode to evaluate their main bioelectrochemical parameters, such as pH dependency, I(max), K(M)(app), detection limit, linear range, operational and storage stability. The obtained results showed a distinctly different behavior for the plant peroxidase electrodes, demonstrating uniquely superior characteristics of the RPTP-based sensors. The broader linear range observed for the RPTP-based biosensor is explained by a high stability of this enzyme in presence of H(2)O(2). The higher storage and operational stability of RPTP-based biosensor as well as its capability to measure hydrogen peroxide under acidic conditions connect with an extremely high thermal and pH-stability of RPTP. 相似文献
55.
Loading of Arabidopsis centromeric histone CENH3 occurs mainly during G2 and requires the presence of the histone fold domain 下载免费PDF全文
The centromeric histone H3 (CENH3) substitutes histone H3 within the nucleosomes of active centromeres in all eukaryotes. CENH3 deposition at centromeres is needed to assemble the kinetochore, a complex of conserved proteins responsible for correct chromosome segregation during nuclear division. Histones of regular nucleosomes are loaded during replication in S phase, while CENH3 deposition deviates from this pattern in yeast, human, and Drosophila melanogaster cells. Little is known about when and how CENH3 targets centromeric loci. Therefore, we determined the location and quantity of recombinant enhanced yellow fluorescent protein (EYFP)-CENH3 in mitotic root and endopolyploid leaf nuclei of transgenic Arabidopsis thaliana cells. Our data indicate significant loading of A. thaliana CENH3 during G2 (before splitting into sister kinetochores) rather than during the S or M phase of the cell cycle. The histone fold domain of the C-terminal part of CENH3 is sufficient to target A. thaliana centromeres. A. thaliana EYFP-CENH3 can recognize and target three different centromeric repeats of Arabidopsis lyrata but not field bean (Vicia faba) centromeres. 相似文献
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57.
Gal Bitan Irena Zeltser Gerardo Byk David Halle Yaffa Mashriki Evgenia V. Gluhov Inna Sukhotinsky Menachem Hanani Zvi Selinger Chaim Gilon 《Journal of peptide science》1996,2(4):261-269
Novel backbone-to-side chain and backbone-to-backbone cyclic analogues of substance P (SP) were prepared by solid-phase synthesis and screened for biological activity. An analogue containing a thioether- lactam ring between positions 9 and 11 showed an EC50 value of 20nM toward the neurokinin 1 (NK-1) and was inactive toward the NK-2 and NK-3 receptors. On the other hand, in a multiple backbone cyclic peptide library of similar analogues, in which the sulphur was excluded from the ring, very low activity was detected. The activity was re-evaluated and was found to be even lower (EC50=0.11 mM ) than the previously published data. These results indicate that the thioether moiety has a crucial role in receptor activation. The results also show tolerance of the NK-1 receptor, but not NK-2 or NK-3, to cyclization of the C-terminal portion of the SP6–11 hexapeptide. 相似文献
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59.
Schwarzenbacher R Jaroszewski L von Delft F Abdubek P Ambing E Biorac T Brinen LS Canaves JM Cambell J Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Eshagi S Floyd R Godzik A Grittini C Grzechnik SK Hampton E Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Ouyang J Page R Quijano K Robb A Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2004,55(3):759-763
60.
Lipophylic compounds from Euphorbia peplis L.--a halophytic plant from the Bulgarian Black Sea coast
Ivanova A Khozin-Goldberg I Kamenarska Z Nechev J Cohen Z Popov S Stefanov K 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(11-12):783-788
The chemical composition of the lipophylic fraction from the halophytic plant Euphorbia peplis L. was investigated. Compared to other terrestrial higher plants an increase of triacylglycerols and especially of glycolipids was observed. The main phospholipid was phosphatidyl choline, followed by almost equal concentrations of phosphatidyl ethanolamine and phosphatidyl glycerol. A relatively high concentration of phosphatidic acids (6.5% of the total phospholipids) was found. The main sterol appeared to be sitosterol and significant amounts of tetracyclic triterpene alcohols were found. The composition of the volatile compounds is relatively simple and only one chlorinated compound, identified as 2,2-diethoxy-1-chloroethane, was found. There was a strong toxicity of the total lipophylic extract towards Artemia salina. 相似文献