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521.
Jagdeep Kaur John Fellers Alok Adholeya Siva L. S. Velivelli Kaoutar El-Mounadi Natalya Nersesian Thomas Clemente Dilip Shah 《Transgenic research》2017,26(1):37-49
Rust fungi of the order Pucciniales are destructive pathogens of wheat worldwide. Leaf rust caused by the obligate, biotrophic basidiomycete fungus Puccinia triticina (Pt) is an economically important disease capable of causing up to 50 % yield losses. Historically, resistant wheat cultivars have been used to control leaf rust, but genetic resistance is ephemeral and breaks down with the emergence of new virulent Pt races. There is a need to develop alternative measures for control of leaf rust in wheat. Development of transgenic wheat expressing an antifungal defensin offers a promising approach to complement the endogenous resistance genes within the wheat germplasm for durable resistance to Pt. To that end, two different wheat genotypes, Bobwhite and Xin Chun 9 were transformed with a chimeric gene encoding an apoplast-targeted antifungal plant defensin MtDEF4.2 from Medicago truncatula. Transgenic lines from four independent events were further characterized. Homozygous transgenic wheat lines expressing MtDEF4.2 displayed resistance to Pt race MCPSS relative to the non-transgenic controls in growth chamber bioassays. Histopathological analysis suggested the presence of both pre- and posthaustorial resistance to leaf rust in these transgenic lines. MtDEF4.2 did not, however, affect the root colonization of a beneficial arbuscular mycorrhizal fungus Rhizophagus irregularis. This study demonstrates that the expression of apoplast-targeted plant defensin MtDEF4.2 can provide substantial resistance to an economically important leaf rust disease in transgenic wheat without negatively impacting its symbiotic relationship with the beneficial mycorrhizal fungus. 相似文献
522.
Oleg I. Artyushin Elena V. Sharova Natalya M. Vinogradova Galina K. Genkina Aleksandra A. Moiseeva Zinaida S. Klemenkova Iana R. Orshanskaya Anna A. Shtro Renata A. Kadyrova Vladimir V. Zarubaev Olga I. Yarovaya Nariman F. Salakhutdinov Valery K. Brel 《Bioorganic & medicinal chemistry letters》2017,27(10):2181-2184
A series of seventeen tetrazole derivatives of 1,7,7-trimethyl-[2.2.1]bicycloheptane were synthesized using click chemistry methodology and characterized by spectral data. Studies of cytotoxicity and in vitro antiviral activity against influenza virus A/Puerto Rico/8/34 (H1N1) in MDCK cells of the compounds obtained were performed. The structure-activity relationship analysis suggests that to possess virus-inhibiting activity, the compounds of this group should bear oxygen atom with a short linker (C2-C4), either as a hydroxyl group (18, 19, 29), keto-group (21) or as a part of a heterocycle (24). These compounds demonstrated low cytotoxicity along with high anti-viral activity. 相似文献
523.
Natalya Romadanova Svetlana Kushnarenko Lazzat Karasholakova 《In vitro cellular & developmental biology. Plant》2017,53(4):382-393
Many cryopreservation techniques are currently available, and it is common for new modifications to be developed for individual crops or specific genotypes. In this study, results of variations of the PVS2 cryopreservation protocol are compared to provide evidence for the suitability of a standard form of this technique for cryopreservation of a range of fruit, berry crops, and potato. Shoot cultures of Malus, Solanum, Lonicera, and Berberis were tested with variations of cold acclimation, pretreatment media, and PVS2 exposure times. A general protocol with some modifications was produced that was suitable for all four genera. The regenerative capacity of shoot tips after cryopreservation by this method exceeded a mean of 50% for Malus, Solanum, Lonicera, and Berberis, which is sufficient for setting storage in a cryobank. After liquid nitrogen storage, the shoot cultures that survived had a healthy appearance and developed rapidly. For each species tested, the only optimization required was the preparation of donor plants by cold acclimation and pretreatment. The choice of one common method simplifies the methodology for conducting experiments and storing a range of germplasm. The use of the PVS2 vitrification method with a 0.3-M sucrose pretreatment is multiuse and can be recommended as the most effective method for the cryopreservation of shoot tips from many plant species. 相似文献
524.
Deichman GI Dyakova NA Matveeva VA Kashkina LM 《Journal of cellular biochemistry》2007,101(5):1148-1164
The hypothesis tested in the study suggests that mechanisms of the earlier described delayed or accelerated tumor progression may be regulated by the antiapoptotic and proapoptotic cellular programs activated in stress reactions of transformed cells to the host normal cellular environment. Therefore, spontaneously transformed hamster cell line STHE, its bcl-2-transduced line STHE-Bcl-2, and 64 of their descendant tumor cell variants naturally selected in two in vivo regimes (local tumor growth versus dissemination) were examined. The role of Bcl-2 and the possible activation of endogenous death-signaling Bax, Ras, and HSP90/HSP70 stress proteins in STHE (Bcl-2+/-) tumor cell variants were studied in dynamics of in vivo tumor progression. The data demonstrate: (1) Immediate in vivo activation of Bax and of HSP90/HSP70 stress proteins in disseminated STHE cells on the background of accelerated tumor progression; (2) No immediate activation of Bax and the gradual downregulation of Bcl-2 in STHE-Bcl-2 cells on the background of delayed tumor progression; (3) Alternative and mutually suppressive character of Bcl-2 and Bax expression in both regimes of tumor progression; (4) In the later stages of tumor progression, the regular transit of the initial Bcl-2 antiapoptotic, Bax-suppressing program, and the delayed tumor progression towards Bcl-2 loss, activation of Bax, and acceleration of tumor progression. Thus, the delay of tumor progression is apparently determined by the ability of Bcl-2-expressing tumor cells to extinguish the cell-damaging environmental stress signals and Bax activation, while its acceleration correlates with Bcl-2 loss, activation of proapoptotic Bax, and tumor cells damage. 相似文献
525.
Presence and localization of three lactic acid transporters (MCT1, -2, and -4) in separated human granulocytes, lymphocytes, and monocytes. 总被引:2,自引:0,他引:2
526.
Belousova N Korokhov N Krendelshchikova V Simonenko V Mikheeva G Triozzi PL Aldrich WA Banerjee PT Gillies SD Curiel DT Krasnykh V 《Journal of virology》2003,77(21):11367-11377
The success of gene therapy depends on the specificity of transgene delivery by therapeutic vectors. The present study describes the use of an adenovirus (Ad) fiber replacement strategy for genetic targeting of the virus to human CD40, which is expressed by a variety of diseased tissues. The tropism of the virus was modified by the incorporation into its capsid of a protein chimera comprising structural domains of three different proteins: the Ad serotype 5 fiber, phage T4 fibritin, and the human CD40 ligand (CD40L). The tumor necrosis factor-like domain of CD40L retains its functional tertiary structure upon incorporation into this chimera and allows the virus to use CD40 as a surrogate receptor for cell entry. The ability of the modified Ad vector to infect CD40-positive dendritic cells and tumor cells with a high efficiency makes this virus a prototype of choice for the derivation of therapeutic vectors for the genetic immunization and targeted destruction of tumors. 相似文献
527.
Sortase A catalyzed ligation of ultra-short peptides leads to inter/intra-molecular transpeptidation to form either linear or cyclic oligomers dependent upon the peptide length. Cyclic peptides were the main products for peptides with more than 15aa. However, for ultra-short (<15aa) peptides, cyclic oligomers became predominant in prolonged reactions. Peptides with 1–3 aminoglycines were equally active but peptide oligomers from peptide containing more than one aminoglycine were prone to hydrolysis. 相似文献
528.
Natalya Seredkina Johan van der Vlag Jo Berden Elin Mortensen Ole Petter Rekvig 《Molecular medicine (Cambridge, Mass.)》2013,19(1):161-169
Autoantibodies to components of chromatin, which include double-stranded DNA (dsDNA), histones and nucleosomes, are central in the pathogenesis of lupus nephritis. How anti-chromatin autoantibodies exert their nephritogenic activity, however, is controversial. One model assumes that autoantibodies initiate inflammation when they cross-react with intrinsic glomerular structures such as components of membranes, matrices or exposed nonchromatin ligands released from cells. Another model suggests glomerular deposition of autoantibodies in complex with chromatin, thereby inducing classic immune complex–mediated tissue damage. Recent data suggest acquired error of renal chromatin degradation due to the loss of renal DNaseI enzyme activity is an important contributing factor to the development of lupus nephritis in lupus-prone (NZBxNZW)F1 mice and in patients with lupus nephritis. Down-regulation of DNaseI expression results in reduced chromatin fragmentation and in deposition of extracellular chromatin–IgG complexes in glomerular basement membranes in individuals who produce IgG anti-chromatin autoantibodies. The main focus of the present review is to discuss whether exposed chromatin fragments in glomeruli are targeted by potentially nephritogenic anti-dsDNA autoantibodies or if the nephritogenic activity of these autoantibodies is explained by cross-reaction with intrinsic glomerular constituents or if both models coexist in diseased kidneys. In addition, the role of silencing of the renal DNaseI gene and the biological consequences of reduced chromatin fragmentation in nephritic kidneys are discussed. 相似文献
529.
530.