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1.
Epifano C Krijnse-Locker J Salas ML Rodríguez JM Salas J 《Journal of virology》2006,80(24):12260-12270
African swine fever virus (ASFV) protein pB602L has been described as a molecular chaperone for the correct folding of the major capsid protein p72. We have studied the function of protein pB602L during the viral assembly process by using a recombinant ASFV, vB602Li, which inducibly expresses the gene coding for this protein. We show that protein pB602L is a late nonstructural protein, which, in contrast with protein p72, is excluded from the viral factory. Repression of protein pB602L synthesis inhibits the proteolytic processing of the two viral polyproteins pp220 and pp62 and leads to a decrease in the levels of protein p72 and a delocalization of the capsid protein pE120R. As shown by electron microscopy analysis of cells infected with the recombinant virus vB602Li, the viral assembly process is severely altered in the absence of protein pB602L, with the generation of aberrant "zipper-like" structures instead of icosahedral virus particles. These "zipper-like" structures are similar to those found in cells infected under restrictive conditions with the recombinant virus vA72 inducibly expressing protein p72. Immunoelectron microscopy studies show that the abnormal forms generated in the absence of protein pB602L contain the inner envelope protein p17 and the two polyproteins but lack the capsid proteins p72 and pE120R. These findings indicate that protein pB602L is essential for the assembly of the icosahedral capsid of the virus particle. 相似文献
2.
In the growing literature on significant dreams, relatively little attention has been given to the enduring, even life-long, influence some dreams have on dreamers' lives. This article describes an ongoing research project on significant dreams by way of an illustrative case of a young woman whose 20-year-old dream still resonates in her psychic life. We suggest that such dreams might be better understood in terms of the aesthetics of & #x201C;image rather than the interpretation of dreams as & #x201C;text. 相似文献
3.
Overexpression of restructured pyruvate dehydrogenase complexes and site-directed mutagenesis of a potential active-site histidine residue. 总被引:1,自引:0,他引:1
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The aceEF-lpd operon of Escherichia coli encodes the pyruvate dehydrogenase (E1p), dihydrolipoamide acetyltransferase (E2p) and dihydrolipoamide dehydrogenase (E3) components of the pyruvate dehydrogenase multienzyme complex (PDH complex). A thermoinducible expression system was developed to amplify a variety of genetically restructured PDH complexes, including those containing three, two, one and no lipoyl domains per E2p chain. Although large quantities of the corresponding complexes were produced, they had only 20-50% of the predicted specific activities. The activities of the E1p components were diminished to the same extent, and this could account for the shortfall in overall complex activity. Thermoinduction was used to express a mutant PDH complex in which the putative active-site histidine residue of the E2p component (His-602) was replaced by cysteine in the H602C E2p component. This substitution abolished dihydrolipoamide acetyltransferase activity of the complex without affecting other E2p functions. The results support the view that His-602 is an active-site residue. The inactivation could mean that the histidine residue performs an essential role in the acetyltransferase reaction mechanism, or that the reaction is blocked by an irreversible modification of the cysteine substituent. Complementation was observed between the H602C PDH complex and a complex that is totally deficient in lipoyl domains, both in vitro, by the restoration of overall complex activity in mixed extracts, and in vivo, from the nutritional independence of strains that co-express the two complexes from different plasmids. 相似文献
4.
Volume 63, no. 2, p. 714, Figure 2: panel b should appear as shown below. FIG. 2b [This corrects the article on p. 710 in vol. 63.]. 相似文献
5.
p63 is the identity switch for uterine/vaginal epithelial cell fate, and disruption of p63 expression by diethylstilbestrol (DES) induces cervical/vaginal adenosis in mice. In this article, we report the expression patterns of p63 isoforms (TA, DeltaN, alpha, beta and gamma) in mice, focusing on the reproductive tract. We also present the reproductive tract phenotype of female p63-/- mice. Finally, to better evaluate the potential role of p63 in human development of DES-induced cervical/vaginal adenosis, we describe the ontogeny of p63 in human female fetuses. In adult mice, the DeltaN isoforms of p63 were expressed only in squamous/basal/myoepithelial cells of epithelial tissues, while TA isoforms of p63 were highly expressed in germ cells of the ovary and testis. In fetal mice, the DeltaN and alpha forms of p63 were expressed in the cloacal and urogenital sinus epithelia. In the female p63-/- mice, the sinus vagina developed, but p63-/- sinus vaginal epithelium failed to undergo squamous differentiation confirming an essential role of p63 in squamous epithelial differentiation. Although TAp63 was highly expressed in developing primordial germ cells/oocytes, p63-/- ovaries and oocytes developed normally. The ontogeny of p63 in female reproductive organs was essentially identical in mouse and human. In the human fetus at the susceptible stage for DES-induced cervical/vaginal adenosis, most cervical/vaginal epithelial cells were columnar and negative for p63. Therefore, inhibition of p63 expression by DES should change the cell fate of human Müllerian duct epithelial cells and cause cervical/vaginal adenosis as previously demonstrated in mouse. 相似文献
6.
Volume 63, no. 8, p. 3183, column 1, line 3 from the bottom: "0.012 versus 0.730" should read "0.022 versus 0.065." [This corrects the article on p. 3182 in vol. 63.]. 相似文献
7.
Vol. 63, no. 9, p. 3468, Table 1, subheading under heading "Total recovery": "((delta)mol)" should read "((mu)mol)." [This corrects the article on p. 3463 in vol. 63.]. 相似文献
8.
Summary A relationship between serine-induced growth sensitivity and the cAMP-CAP complex is established. Mutants of Escherichia coli K 12 deficient either in the cya or crp gene function exhibit a resistant phenotype on serine media although they harbor a relA allele normally leading to sensitivity toward serine. The presence of a crp
* allele in a cya
rela background restores the sensitivity phenotype, while the analysis of serine resistant mutants selected from a crp
*
cya
relA strains shows that the mutation leading to resistance is located at, or very near, the crp gene, giving a more or less Crp- phenotype. In addition crp
*
cya
relA strains excrete large quantities of 2-ketobutyrate when grown on glucose M63 medium. This excretion is unambiguously linked to the presence of the crp
* allele and is correlated with an enhanced threonine deaminase activity. Besides, the complex regulation exerted on the acetolactate synthase activities is discussed. 相似文献
9.
Inactivation of Cryptosporidium parvum Oocysts and Clostridium perfringens Spores by a Mixed-Oxidant Disinfectant and by Free Chlorine 总被引:1,自引:0,他引:1
Volume 63, no. 4, p. 1600: The caption to Table 2 should read as follows: "Inactivation of Clostridium perfringens spores by 5-mg/liter doses of mixed oxidants or free chlorine in buffer at pH 7 at 25(deg)C." [This corrects the article on p. 1598 in vol. 63.]. 相似文献
10.
[This corrects the article on p. 4276 in vol. 63.]. 相似文献
11.
[This corrects the article on p. 4430 in vol. 63.]. 相似文献
12.
Seasonality in antarctic airborne fungal spores 总被引:1,自引:0,他引:1
Marshall WA 《Applied and environmental microbiology》1998,64(3):1167
[This corrects the article on p. 2243 in vol. 63.]. 相似文献
13.
[This corrects the article on p. 4841 in vol. 63.]. 相似文献
14.
Paradoxical role of capsule in murine bronchoalveolar macrophage-mediated killing of Cryptococcus neoformans 总被引:18,自引:0,他引:18
Infections with the encapsulated fungus Cryptococcus neoformans are usually acquired via inhalation, and the presence of a capsule has been identified as a virulence factor. Therefore, we studied murine bronchoalveolar macrophage (BAM)-mediated killing and phagocytosis of encapsulated and acapsular strains of C. neoformans. After 2 h, BAM killed encapsulated strains CN52 and MP415 more readily than acapsular strains CN602 and CAP67 (54.9 and 36.2% vs 26.1 and 6.7%, respectively, p less than 0.001). Pre-incubating CN602 with purified capsular polysaccharide increased killing to 42.7% (p = 0.04). Significantly greater killing of the encapsulated strains also occurred in vivo. BAM-mediated killing of CN52 appeared to proceed by non-oxidative mechanisms, as BAM released minimal amounts of H2O2 after stimulation with CN52, and killing was not reduced by inhibitors or scavengers of the respiratory burst. The association between encapsulation and susceptibility to BAM fungicidal effects was not attributable to differences in yeast ingestion. Using the same low ratio of organisms to BAM as in the killing assay, greater than 95% of both CN52 and CN602 were phagocytosed. However, BAM phagocytosed significantly greater numbers of acapsular CN602 when incubated with a higher inoculum. Phagocytosis and killing of CN52 and CN602 required fresh serum as a source of C. Phagocytosis of CN52, but not CN602, was profoundly inhibited if BAM were plated on surfaces coated with mAb against the C3bR (CR1). mAb against the iC3b receptor (CR3) did not affect phagocytosis of either strain. These data demonstrate the innate ability of BAM to preferentially kill, by apparently non-oxidative mechanisms, an encapsulated as opposed to acapsular organism. Inasmuch as different receptors appear involved in phagocytosis of encapsulated versus acapsular C. neoformans, the disparity in killing may result from the greater ability of receptors mediating uptake of encapsulated organisms to trigger the antimicrobial armamentarium of the BAM. 相似文献
15.
Waanders E Croes HJ Maass CN te Morsche RH van Geffen HJ van Krieken JH Fransen JA Drenth JP 《Histochemistry and cell biology》2008,129(3):301-310
Polycystic liver disease (PCLD) is an inherited disorder caused by mutations in either PRKCSH (hepatocystin) or SEC63 (Sec63p). However, expression patterns of the implicated proteins in diseased and normal liver are unknown. We analyzed subcellular
and cellular localization of hepatocystin and Sec63p using cell fractionation, immunofluorescence, and immunohistochemical
methods. Expression patterns were assessed in fetal liver, PCLD liver, and normal adult liver. We found hepatocystin and Sec63p
expression predominantly in the endoplasmic reticulum. In fetal tissue, there was intense expression of hepatocystin in ductal
plate, bile ducts, and hepatocytes. However, Sec63p staining was prominent in early hepatocytes only and weak in bile ducts
throughout development. In PCLD tissue, hepatocystin was expressed in hepatocytes, bile ducts, and in cyst epithelium of patients
negative for PRKCSH mutation. In contrast, the majority of cysts from PRKCSH mutation carriers did not express hepatocystin. Sec63p expression was observed in all cyst epithelia regardless of mutational
state. We conclude that hepatocystin is probably required for development of bile ducts and does not interact with Sec63p.
The results support the hypothesis that cyst formation in PCLD results from a cellular recessive mechanism involving loss
of hepatocystin. Cystogenesis in SEC63-associated PCLD occurs via a different mechanism.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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18.
Nakata H Maeda K Miyakawa T Shibayama S Matsuo M Takaoka Y Ito M Koyanagi Y Mitsuya H 《Journal of virology》2005,79(4):2087-2096
We established human peripheral blood mononuclear cell (PBMC)-transplanted R5 human immunodeficiency virus type 1 isolate JR-FL (HIV-1(JR-FL))-infected, nonobese diabetic-SCID, interleukin 2 receptor gamma-chain-knocked-out (NOG) mice, in which massive and systemic HIV-1 infection occurred. The susceptibility of the implanted PBMC to the infectivity and cytopathic effect of R5 HIV-1 appeared to stem from hyperactivation of the PBMC, which rapidly proliferated and expressed high levels of CCR5. When a novel spirodiketopiperazine-containing CCR5 inhibitor, AK602/ONO4128/GW873140 (molecular weight, 614), was administered to the NOG mice 1 day after R5 HIV-1 inoculation, the replication and cytopathic effects of R5 HIV-1 were significantly suppressed. In saline-treated mice (n = 7), the mean human CD4(+)/CD8(+) cell ratio was 0.1 on day 16 after inoculation, while levels in mice (n = 8) administered AK602 had a mean value of 0.92, comparable to levels in uninfected mice (n = 7). The mean number of HIV-RNA copies in plasma in saline-treated mice were approximately 10(6)/ml on day 16, while levels in AK602-treated mice were 1.27 x 10(3)/ml (P = 0.001). AK602 also significantly suppressed the number of proviral DNA copies and serum p24 levels (P = 0.001). These data suggest that the present NOG mouse system should serve as a small-animal AIDS model and warrant that AK602 be further developed as a potential therapeutic for HIV-1 infection. 相似文献
19.
p63, known to play a role in development, has more recently also been implicated in cancer progression. Mutations in p63 have been shown to be responsible for several human developmental diseases. Differential splicing of the p63 gene gives rise to p63 isoforms, which can act either as tumor suppressors or as oncogene. In this report, we studied the effects of naturally occurring TAp637 mutants on the regulation of p53/p63 and p63 specific target genes. We observed significant differences among p63 mutants to regulate the p53/p63 and p63 specific target genes. Additionally, we observed a differential effect of p63 mutants on wildtype-p63-mediated induction ofp53/p63 and p63 specific target genes. We also demonstrated that these mutants differentially regulate the binding of wildtype p63 to the promoter of target genes. Furthermore, the effects of these mutants on cell death and survival were consistent with their ability to regulate the downstream targets when compared to wildtype TAp63T. In summary, our data demonstrate that p63 mutants exhibit differential effects on p63 and p53/p63 specific target genes and on the induction of apoptosis, and provide further insight into the function of p63. 相似文献
20.
Assignment to chromosome 12 of the gene coding for the human cell surface antigen CD9(p24) using the monoclonal antibody ALB6 总被引:2,自引:0,他引:2
C Boucheix J Y Nguyen-van-CongPerrot C Foubert M S Gross D Weil V Laisney C Rosenfeld J Frezal 《Annales de génétique》1985,28(1):19-24
An analysis of 20 independent man-mouse and man-hamster hybrids has shown that the gene coding for the cell-surface protein CD9(p24), a differentiation antigen recognized by the monoclonal antibody ALB6, is located on chromosome 12. A positive correlation was shown between CD9(p24) and chromosome 12 and all other chromosomes were excluded. In addition a synteny was observed between CD9(p24) and LDH-B, a well known marker of chromosome 12 (out of 27 hybrids, 15 were LDH-B+ ALB6+ and 12 were LDH-B-ALB6-). Expression of the antigen in hybrid CH-35K issued from parental fibroblasts possessing a balanced reciprocal translocation 46,X,Y,t(X,12)(q23,q12) indicated that the gene for CD9(p24) is probably localized on 12q12----pter. Monoclonal antibodies ALB6, Ba2 and 602/29 recognize the same protein of molecular weight 21 to 24 KD controlled by a gene located on chromosome 12. It is known that Ba2 and 602/29 recognize two different epitopes but the existence of a third epitope recognized by ALB6 remains to be shown. 相似文献