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91.
Open reading frame S/L of varicella-zoster virus encodes a cytoplasmic protein expressed in infected cells 下载免费PDF全文
Kemble GW Annunziato P Lungu O Winter RE Cha TA Silverstein SJ Spaete RR 《Journal of virology》2000,74(23):11311-11321
We report the discovery of a novel gene in the varicella-zoster virus (VZV) genome, designated open reading frame (ORF) S/L. This gene, located at the left end of the prototype VZV genome isomer, expresses a polyadenylated mRNA containing a splice within the 3' untranslated region in virus-infected cells. Sequence analysis reveals significant differences between the ORF S/Ls of wild-type and attenuated strains of VZV. Antisera raised to a bacterially expressed portion of ORF S/L reacted specifically with a 21-kDa protein synthesized in cells infected with a VZV clinical isolate and with the original vaccine strain of VZV (Oka-ATCC). Cells infected with other VZV strains, including a wild-type strain that has been extensively passaged in tissue culture and commercially produced vaccine strains of Oka, synthesize a family of proteins ranging in size from 21 to 30 kDa that react with the anti-ORF S/L antiserum. MeWO cells infected with recombinant VZV harboring mutations in the C-terminal region of the ORF S/L gene lost adherence to the stratum and adjacent cells, resulting in an altered plaque morphology. Immunohistochemical analysis of VZV-infected cells demonstrated that ORF S/L protein localizes to the cytoplasm. ORF S/L protein was present in skin lesions of individuals with primary or reactivated infection and in the neurons of a dorsal root ganglion during virus reactivation. 相似文献
92.
T I Buzhievskaia T L Cha?kovskaia G V Skiban T E Zerova-Liubimova T P Kochube? 《T?Sitologii?a i genetika》1988,22(3):25-29
Three unusual cases of Down's syndrome inheritance are presented which permit supposing that microstructural chromosome aberrations in parents may induce not only a structural imbalance of chromosomal material in progeny, but also a numerical imbalance. 相似文献
93.
Seo JW Srisook E Son HJ Hwang O Cha YN Chi DY 《Bioorganic & medicinal chemistry letters》2005,15(14):3369-3373
Sixteen derivatives of N-acetyl-3-O-methyldopamine (NAMDA), an inhibitor of BH4 synthesis, were designed and synthesized. The ability of these derivatives to inhibit NO and BH4 production by lipopolysaccharide-stimulated BV-2 microglial cells was determined. While NAMDA at 100 microM inhibited NO and BH4 production by only about 20%, its catecholamide 8, indole 23 derivative, 13, and N-acetyl tetrahydroisoquinoline 25 inhibited the NO production by >50% at the same concentration. In particular, 13 and 25 inhibited both NO and BH4 production to similar degrees, which suggested that these compounds might inhibit NO production by blocking BH4-dependent dimerization of the newly synthesized iNOS monomer. 相似文献
94.
Phylogenetic placement of Cibicidoides wuellerstorfi (Schwager, 1866) from methane seeps and non‐seep habitats on the Pacific margin 下载免费PDF全文
A. M. Burkett A. E. Rathburn M. E. Pérez L. A. Levin H. Cha G. W. Rouse 《Geobiology》2015,13(1):44-52
Benthic foraminifera are among the most abundant groups found in deep‐sea habitats, including methane seep environments. Unlike many groups, no endemic foraminiferal species have been reported from methane seeps, and to our knowledge, genetic data are currently sparse for Pacific deep‐sea foraminifera. In an effort to understand the relationships between seep and non‐seep populations of the deep‐sea foraminifera Cibicidoides wuellerstorfi, a common paleo‐indicator species, specimens from methane seeps in the Pacific were analyzed and compared to one another for genetic similarities of small subunit rDNA (SSU rDNA) sequences. Pacific Ocean C. wuellerstorfi were also compared to those collected from other localities around the world (based on 18S gene available on Genbank, e.g., Schweizer et al., 2009). Results from this study revealed that C. wuellerstorfi living in seeps near Costa Rica and Hydrate Ridge are genetically similar to one another at the species level. Individuals collected from the same location that display opposite coiling directions (dextral and sinstral) had no species level genetic differences. Comparisons of specimens with genetic information available from Genbank (SSU rDNA) showed that Pacific individuals, collected for this study, are genetically similar to those previously analyzed from the North Atlantic and Antarctic. These observations provide strong evidence for the true cosmopolitan nature of C. wuellerstorfi and highlight the importance of understanding how these microscopic organisms are able to maintain sufficient genetic exchange to remain within the same species between seep and non‐seep habitats and over global distances. 相似文献
95.
常绿杜鹃亚属Subgenus Hymenanthes是由K.Koch(1872)根据Blume(1826)建立的Genus Hymenanthes改级组合而成。但长期以来人们一直沿用了Maximowicz(1870)所建立的、后由Koehne(1893)修订过的Subgenus Eurhododendron这一亚属名称,直到最近D.F.Chamberlain(1978,1979,1982)对该亚属的名称才作了正式订正。 相似文献
96.
Simpler is better: fewer non‐target insects trapped with a four‐component chemical lure vs. a chemically more complex food‐type bait for Drosophila suzukii 下载免费PDF全文
Dong H. Cha Stephen P. Hesler Shinyoung Park Todd B. Adams Richard S. Zack Helmuth Rogg Gregory M. Loeb Peter J. Landolt 《Entomologia Experimentalis et Applicata》2015,154(3):251-260
Baits – fermented food products – are generally attractive to many types of insects, which makes it difficult to sort through non‐target insects to monitor a pest species of interest. We test the hypothesis that a chemically simpler and more defined attractant developed for a target insect is more specific and attracts fewer non‐target insects than a chemically more complex food‐type bait. A four‐component chemical lure isolated from a food bait and optimized for the spotted wing drosophila (SWD), Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), was compared to the original wine/vinegar bait to assess the relative responses of non‐target insects. In several field experiments in Washington State, USA, it was shown that numbers of pest muscid flies, cutworm and armyworm moths, and pest yellowjackets were reduced in traps baited with the chemical lure compared to the wine/vinegar bait. In other field experiments in the states of Washington, Oregon, and New York, numbers of non‐target drosophilid flies were also reduced in traps baited with the chemical lure relative to wine/vinegar bait. In Washington, numbers of Drosophila melanogaster Meigen and Drosophila obscura Fallen species groups and Drosophila immigrans Sturtevant were reduced in the chemical lure traps, whereas in New York, D. melanogaster and D. obscura species groups, D. immigrans, Drosophila putrida Sturtevant, Drosophila simulans Sturtevant, Drosophila tripunctata Loew, and Chymomyza spp. numbers were reduced. In Oregon, this same effect was observed with the D. melanogaster species group. Taken together, these results indicate that the four‐component SWD chemical lure will be more selective for SWD compared to fermentation baits, which should reduce time and cost involved in trapping in order to monitor SWD. 相似文献
97.
More than 750 plants were regenerated from protoplasts isolated from microspore callus-derived cell suspensions of the Mediterranean japonica rice Miara, using a nurse-feeder technique and N6-based culture medium. The mean plating efficiency and the mean regeneration ability of the protocalluses were 0.5% and 49% respectively. Flow cytometric evaluation of the DNA contents of 7 month old-cell and protoplast suspensions showed that they were still haploid. Contrastingly, the DNA contents of leaf cell nuclei of the regenerated protoclones ranged from 1C to 5C including 60% 2C plants. This was consistent with the morphological type and the fertility of the mature plants. These results and the absence of chimeric plants suggest that polyploidization occurred during the early phase of protoplast culture.Abbreviations BAP
6-benzylamino purine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- FDA
fluorescein diacetate
- GA3
gibberellic acid
- NAA
-naphthaleneacetic acid
- PAS
periodic acid Schiff
- PCM
protoplast culture medium
- PCV
packed cell volume 相似文献
98.
Yi T Lee HL Cha JH Ko SI Kim HJ Shin HI Woo KM Ryoo HM Kim GS Baek JH 《Journal of cellular physiology》2008,217(2):409-422
The epidermal growth factor receptor (EGFR) functions in various cellular physiological processes such as proliferation, differentiation, and motility. Although recent studies have reported that EGFR signaling is involved in osteoclast recruitment and formation, the molecular mechanism of EGFR signaling for the regulation of osteoclastogenesis remains unclear. We investigated the role of the EGFR in osteoclast differentiation and survival and show that the expression of the EGFR was highly up-regulated by receptor activator of nuclear factor-kappaB ligand (RANKL) during osteoclast differentiation. EGFR-specific tyrosine kinase inhibitors and EGFR knockdown blocked RANKL-dependent osteoclast formation, suggesting that EGFR signaling plays an important role in osteoclastogenesis. EGFR inhibition impaired the RANKL-mediated activation of osteoclastogenic signaling pathways, including c-Jun N-terminal kinase (JNK), NF-kappaB, and Akt/protein kinase B (PKB). In addition, EGFR inhibition in differentiated osteoclasts caused apoptosis through caspase activation. Inhibition of the phosphoinositide-3 kinase (PI3K)-Akt/PKB pathway and subsequent activation of BAD and caspases-9 and -3 may be responsible for the EGFR inhibition-induced apoptosis. The EGFR physically associated with receptor activator of nuclear factor-kappaB (RANK) and Grb2-associated binder 2 (Gab2). Moreover, RANKL transactivated EGFR. These data indicate that EGFR regulates RANKL-activated signaling pathways by cross-talking with RANK, suggesting that the EGFR may play a crucial role as a RANK downstream signal and/or a novel type of RANK co-receptor in osteoclast differentiation and survival. 相似文献
99.
Sung Eun Sim Yoon Hee Chung Ji Hoon Jeong Sin Weon Yun Hyoun-Sub Lim Daejin Kim Sung Su Kim Won Bok Lee Choong Ik Cha 《Journal of molecular histology》2009,40(2):157-163
In the present study, we performed immunohistochemical studies to investigate the changes of insulin-like growth factor binding
protein 2 (IGFBP2) in the central nervous system of SOD1G93A mutant transgenic mice as an in vivo model of amyotrophic lateral sclerosis (ALS). Decreased immunoreactivity for IGFBP2
was observed in the cerebral cortex, hippocampus and brainstem of SOD1G93A transgenic mice. In the cerebral cortex, the number of IGFBP2-positive cells was decreased in the somatomotor area, somatosensory
area, auditory area, visual area, entorhinal area, piriform area and prefrontal area. In the hippocampal formation, IGFBP2
immunoreactivity was significantly decreased in the CA1-3 areas and the dentate gyrus. In the brainstem, few IGFBP2-immunoreactive
cells were observed in the medullary and pontine reticular formation, vestibular nucleus, trigeminal motor nucleus, facial
nucleus, hypoglossal nucleus and raphe nucleus. In the spinal cord, IGFBP2 immunoreactivity was not significantly decreased
in SOD1G93A transgenic mice. This study showing decreased IGFBP2 in different brain regions of SOD1G93A transgenic mice may provide clues for understanding differential susceptibility of neural structures in ALS.
S. E. Sim and Y. H. Chung have contributed equally to this work. 相似文献
100.
Adams BS Cha HC Cleary J Haiying T Wang H Sitwala K Markovitz DM 《Arthritis research & therapy》2003,5(4):R226-R233
Using electrophoretic mobility shift assays, we examined sequence-specific binding of DEK, a potential autoantigen in juvenile
rheumatoid arthritis, to conserved Y-box regulatory sequences in class II MHC gene promoters. Nuclear extracts from several
cell lines of different phenotypes contained sequence-specific binding activity recognizing DRA, DQA1*0101, and DQA1*0501 Y-box sequences. Participation of both DEK and NF-Y in the DQA1 Y-box binding complex was confirmed by 'supershifting' with anti-DEK and anti-NF-Y antibodies. Recombinant DEK also bound
specifically to the DQA1*0101 Y box and to the polymorphic DQA1*0501 Y box, but not to the consensus DRA Y box. Measurement of the apparent dissociation constants demonstrated a two- to fivefold difference in DEK binding to the
DQA1 Y-box sequence in comparison with other class II MHC Y-box sequences. Residues that are crucial for DEK binding to the DQA1*0101 Y box were identified by DNase I footprinting. The specific characteristics of DEK binding to these related sequences suggests
a potential role for DEK in differential regulation of class II MHC expression, and thus in the pathogenesis of juvenile rheumatoid
arthritis and other autoimmune diseases. 相似文献