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51.
52.
PTEN is a tumor suppressor with dual protein and lipid–phosphatase activity, which is frequently deleted or mutated in many human advanced cancers. Recent studies have also demonstrated that PTEN is a promising target in type II diabetes and obesity treatment. Using C-terminal PTEN sequence in pEG202–NLS as bait, yeast two-hybrid screening on Mouse Embryo, Colon Cancer, and HeLa cDNA libraries was carried out. Isolated positive clones were validated by mating assay and identified through automated DNA sequencing and BLAST database searches. Sequence analysis revealed a number of PTEN-binding proteins linking this phosphatase to a number of different signaling cascades, suggesting that PTEN may perform other functions besides tumor-suppressing activity in different cell types. In particular, the interplay between PTEN function and adipocyte-specific fatty-acid-binding protein FABP4 is of notable interest. The demonstrable tautology of PTEN to FABP4 suggested a role for this phosphatase in the regulation of lipid metabolism and adipocyte differentiation. This interaction was further studied using coimmunoprecipitation and gel-filtration assays. Finally, based on Biacore assay, we have calculated the K D of PTEN–FABP4 complex, which is around 2.8 μM.  相似文献   
53.
Novel hydrazones of the lupane and 19β,28-epoxy-18α-oleanane types have been synthesized via the interaction of 2,3-secotriterpenic aldehydonitriles with substituted hydrazines. As a result of the investigation of the antiviral activity of 2,3-secotriterpenic hydrazones against the Indiana strain of the vesicular stomatitis virus on two models of mammalian cell line infection, the acetylhydrazone of 1-cyano-2,3-seco-19β,28-epoxy-18α-olean-3-al has been found to have a high prophylactic activity of 0.00016 μg/ml to the vesicular stomatitis virus and to inhibit virus reproduction in primarily infected cells in a 0.21-μg/ml concentration.  相似文献   
54.
We describe the extra bony elements, plates, and osteoderms present in species of the genus Brachycephalus. Samples of eight species of Brachycephalus, including seven populations of Brachycephalus ephippium, were examined. The large additional elements associated with the skull (parotic plate) and vertebrae (vertebral and paravertebral plates) all comprise intramembranous bone, similar to that of the frontoparietal or nasal bones of the skull of most of frogs. Additionally, in the dermis of one unnamed species, we discovered and described true osteoderms. We discuss the morphological nature and diversity of theses elements and their importance as evidence of phylogenetic relationship within Brachycephalus. In summary, three distinct conditions of extra bony elements occur in the genus Brachycephalus: (1) bony plates may be present or absent in species of the genus; (2) a few, small bony plates may be developed and these may be represented by (a) paravertebral plates small and restricted to the distal ends of the transverse processes of the presacral IV, (b) parotic plates small and not covering the tops of the squamosals, and (c) ornamented spinal plates on all vertebrae; and (3) well‐developed bony plates may be present as (a) paravertebral plates forming a ‘bone‐shield’ on the dorsal surface of the trunk, ornamented, and visible through the integument, (b) parotic plates covering the tops of the squamosals, and (c) spinal plates associated with all vertebrae, and ornamented on vertebrate I–VI. Although the phenomenon of miniaturization may be associated with the appearance of new elements in at least some of the species in the genus, the traditional rule may not be universally applicable. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 752–767.  相似文献   
55.
A new species of Daptonema is described based upon morphological characters and 18S rRNA sequence. Daptonema matrona sp. nov. was collected in Pina Basin (north‐eastern Brazil). It differs from all other species of the genus by the presence of reduced cephalic setae and straight spicules. These features require an adaptation of the generic diagnosis. Moreover, the females are characterized by intra‐uterine development of the offspring, considered herein as their major autapomorphic feature. Molecular systematic analyses supported Daptonema matrona sp. nov. as a distinct genetic and evolutionary lineage. The data also indicate hypotheses of taxonomic synonymies amongst some related taxa from Xyalidae as well as the paraphyly of Daptonema. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 1–15.  相似文献   
56.
In Myrtaceae (Myrteae), the diploid chromosome number 2 n  = 2 x  = 22 is the most common, although variations of ploidy level occur, with some triploid (2 n  = 3 x  = 33) and tetraploid (2 n  = 4 x  = 44) records. Karyotype details in this group are scarce because the chromosomes are small (< 2 μm). In this work, we carried out a karyotypic analysis of 15 species of Myrtaceae grouped in different subtribes and genera. Measurements of chromosome length (long arm, L ; short arm, S ) were taken and several karyotypic parameters were calculated for each species. The karyotypes in fleshy-fruited taxa (Myrteae) were more varied than in the other previously analysed dry-fruited group ( Eucalyptus , Eucalypteae), in which the chromosomes were exclusively metacentric.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155 , 571–580.  相似文献   
57.
58.
Transgenic popato plants have been created which express recombinant proteins, analogues of spidroin 1, the protein of the cobweb skeleton thread. Expression of the hybrid spidroin 1 genes possessing some repeated sequences retains both in the model test-tube-growing plants and in the crops. Expression level of the synthetic spidroin 1 genes and the level of accumulation of their products in plants depend on the type of promoter, number of repeats, organ specificity and plant species but not on the duration of plant material storage. The results show that the strategy based on constuction and expression of hybrid proteins which include the reporter protein makes it easier to select and analyse expression of hybrid proteins in transgenic organisms.  相似文献   
59.
Molecular Biology - Immunofluorescent method by flow cytometry was used to quantify the expression of the tumor-associated protein βIII-tubulin (TUBB3) in the tissue of urothelial bladder...  相似文献   
60.
Molecular Biology - The substrate properties of nitrogen-base modified derivatives of purine and pyrimidine deoxynucleoside triphosphates during their simultaneous pairwise insertion into the...  相似文献   
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