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41.
Potential porcine circovirus type 2 (PCV2) capsid protein epitopes, suitable for expression on the surface of cucumber mosaic virus (CMV) particles were determined by a thorough analysis of the predicted PCV capsid protein structure. The ab initio protein structure prediction was carried out with fold recognition and threading methods. The putative PCV epitopes were selected on the basis of PCV virion models and integrated into the plant virus coat protein, after amino acid position 131. The recombinants were tested for infectivity and stability on different Nicotiana species and stable recombinant virus particles were purified. The particles were tested for their ability to bind to PCV induced porcine antibodies and used for specific antibody induction in mice and pigs. The results showed that PCV epitopes expressed on the CMV surface were recognized by the porcine antibodies and they were also able to induce PCV specific antibody response. Challenge experiment with PCV2 carried out in immunized pigs showed partial protection against the infection. Based on these results it was concluded that specific antiviral vaccine production for the given pathogen was feasible, offering an inexpensive way for the mass production of such vaccines.  相似文献   
42.
cDNA clones encoding zinc finger motifs were isolated by screening human placenta and T-cell (Peer) cDNA libraries with zinc finger (ZNF) consensus sequences. Unique cDNA clones were mapped in the human genome by rodent-human somatic cell hybrid analysis and in some cases in situ chromosomal hybridization. ZNF 80 mapped to 3p12-3qter, ZNF 7 was previously mapped to 8q24 and is here shown by in situ hybridization and use of appropriate hybrids to map telomeric to the MYC locus. ZNF 79 mapped to 9q34 centromeric to the ABL gene and between a constitutional chromosomal translocation on the centromeric side and the CML specific ABL translocation on the telomeric side. ZNF77 mapped to 19p while ZNF 78L1 (pT3) mapped to 19q. Chromosome 19 carries many ZNF loci and other genes with zinc finger encoding motifs; the pT3 clone additionally detected a locus designated ZNF 78L2, which mapped to chromosome region 1p, most likely in the region 1p32 where the MYCL and JUN loci map.  相似文献   
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Chromosomal mutations and mixoploidy have been revealed in the seedlings of Scots pine (Pinus sylvestris) growing in a hydromorphic environment. A giant chromosome was detected for the first time in gymnosperms.  相似文献   
45.
The great powers of regeneration shown by freshwater planarians, capable of regenerating a complete organism from any tiny body fragment, have attracted the interest of scientists throughout history. In 1814, Dalyell concluded that planarians could "almost be called immortal under the edge of the knife". Equally impressive is the developmental plasticity of these platyhelminthes, including continuous growth and fission (asexual reproduction) in well-fed organisms, and shrinkage (degrowth) during prolonged starvation. The source of their morphological plasticity and regenerative capability is a stable population of totipotent stem cells--"neoblasts"; this is the only cell type in the adult that has mitotic activity and differentiates into all cell types. This cellular feature is unique to planarians in the Bilateria clade. Over the last fifteen years, molecular studies have begun to reveal the role of developmental genes in regeneration, although it would be premature to propose a molecular model for planarian regeneration. Genomic and proteomic data are essential in answering some of the fundamental questions concerning this remarkable morphological plasticity. Such information should also pave the way to understanding the genetic pathways associated with metazoan somatic stem-cell regulation and pattern formation.  相似文献   
46.
The serine/threonine kinase HIPK2 phosphorylates the p53 protein at Ser 46, thus promoting p53-dependent gene expression and subsequent apoptosis. Here, we show that DNA damaging chemotherapeutic drugs cause degradation of endogenous HIPK2 dependent on the presence of a functional p53 protein. Early induced p53 allows caspase-mediated cleavage of HIPK2 following aspartic acids 916 and 977. The resulting C-terminally truncated HIPK2 forms show an enhanced induction of the p53 response and cell death, thus allowing the rapid amplification of the p53-dependent apoptotic program during the initiation phase of apoptosis by a regulatory feed-forward loop. The active HIPK2 fragments are further degraded during the execution and termination phase of apoptosis, thus ensuring the occurrence of HIPK2 signaling only during the early phases of apoptosis induction.  相似文献   
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A lichen biodiversity study conducted in the Khanty-Mansi Autonomous Okrug (district) reports 958 species in 199 genera and 72 families. Cetrelia alaskana (Llano) W. L. Culb. et C. F. Culb. is new to West Siberia; Graphis elegans (Borrer ex Sm.) Ach., Porpidia hydrophila (Fr.) Hertel et A. J. Schwab, and Sclerococcum sphaerale (Ach.) Fr. are new to Siberia; Acarospora fusca B. de Lesd., Cliostomum tenerum (Nyl.) Coppins et S. Ekman, Pertusaria corallina (L.) Arnold, and P. stalactiza Nyl. are new to Russia. High diversity of epilithic lichens is ecologically due to a variety of ecotopes that include mountain habitats on the eastern spurs of the Subarctic and Northern Urals in addition to plain ones.  相似文献   
49.
The comparative analysis of the infectious process and immunological parameters in (CBA x C57BL/6)F1 mice infected with S. typhimurium isogenic strains differing by the presence of plasmid pR50 determining protease activity, was carried out. A growth in the expression level of antilactoferrin, anticomplementary and anti-immunoglobulin activity in bacteria isolated from the spleen in the course of the infectious process was detected. In mice infected with S. typhimurium having plasmid pR50, in contrast to nonplasmid recipients, a higher level of contamination of organs, the suppression of spontaneous, stimulated production of interferon-gamma and the bactericidal properties of peritoneal macrophages were noted. The data obtained in this investigation suggested that the acquisition of R-plasmid of 50 MD, controlling protease activity and multiple medicinal resistance, contributed to the persistence of intracellular bacteria.  相似文献   
50.
Four sets of p53-binding proteins are discussed in this review. These are the E2F family, the ASPP family, Y-box-binding protein YB1, and the prolyl isomerase Pin1. Each appears to play a role in the decision by p53 to induce an arrest of cell proliferation or apoptosis and they may also be independent markers of cancer. Their activities appear to be linked with the cell cycle and they may also interact with each other. In this review, the properties of each protein class are discussed as well as how they affect p53 functions. A model is proposed as to how their activities might be coordinated.  相似文献   
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