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101.
In metazoans, nuclear export of bulk mRNA is mediated by Tap‐p15, a conserved heterodimeric export receptor that cooperates with adaptor RNA‐binding proteins. In this article, we show that Thoc5, a subunit of the mammalian TREX complex, binds to a distinct surface on the middle (Ntf2‐like) domain of Tap. Notably, adaptor protein Aly and Thoc5 can simultaneously bind to non‐overlapping binding sites on Tap‐p15. In vivo, Thoc5 was not required for bulk mRNA export. However, nuclear export of HSP70 mRNA depends on both Thoc5 and Aly. Consistent with a function as a specific export adaptor, Thoc5 exhibits in vitro RNA‐binding activity and is associated with HSP70 mRNPs in vivo as a component of the stable THO complex. Thus, through the combinatorial use of an adaptor (e.g., Aly) and co‐adapter (e.g., Thoc5), Tap‐p15 could function as an export receptor for different classes of mRNAs. 相似文献
102.
The increasing popularity of conditional knockout (KO) technology has resulted in the demand for efficient FLP deleter mice. In addition, FLP deleters are needed in genetic backgrounds that are suited to behavioral studies. We generated CAG-FLPe transgenic (Tg) mice with the C57BL/6J genetic background, which is one of the most commonly-used strains in behavioral studies. We assessed the recombination efficiency of the CAG-FLPe-Tg lines by crossing them with a mouse line carrying a FRT-PGK-neo-FRT cassette. Four of five independent CAG-FLPe lines induced recombination in most (91%-100%) of their progenies, although a small fraction (0%-30%, depending on the line) showed mosaic recombination patterns. These animals are highly potent as deleters of FRT cassettes and are useful for behavioral studies involving conditional KO mice. 相似文献
103.
Yoshinaga T Akiyama K Nishida S Nakane M Ogawa K Hirose H 《Diseases of aquatic organisms》2007,78(2):155-160
A medium for the in vitro culture of Cryptocaryon irritans, which is an obligatorily parasitic ciliate of marine teleosts and causes 'white spot disease', was developed. The medium consisted of a layer of cultured fish cells (FHM), with an agarose gel layer covering the cell layer. The agarose gel contained 0.22% agarose, 10% fetal calf serum, 100 I.U. ml(-1) Penicillin G potassium and 100 microg ml(-1) streptomycin sulphate. Theronts of C. irritans transformed to trophonts and grew to 180 microm in mean length in the medium, although they gradually decreased in number. When trophonts fully developed in medium were transferred into seawater 4 d after inoculation, approximately 70% of them transformed to encysted tomonts and released theronts. When fish were challenged with theronts obtained from in vitro-raised parasites, approximately 40% of the theronts were recovered from fish, indicating comparative infectivity of in vitro-raised theronts to those of in vivo-raised theronts. This is the first report that C. irritans fully developed in vitro and its entire life cycle was completed without a host fish. 相似文献
104.
Protective role of macrophages in noninflammatory lung injury caused by selective ablation of alveolar epithelial type II Cells 总被引:2,自引:0,他引:2
Miyake Y Kaise H Isono K Koseki H Kohno K Tanaka M 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(8):5001-5009
Macrophages have a wide variety of activities and it is largely unknown how the diverse phenotypes of macrophages contribute to pathological conditions in the different types of tissue injury in vivo. In this study we established a novel animal model of acute respiratory distress syndrome caused by the dysfunction of alveolar epithelial type II (AE2) cells and examined the roles of alveolar macrophages in the acute lung injury. The human diphtheria toxin (DT) receptor (DTR), heparin-binding epidermal growth factor-like growth factor (HB-EGF), was expressed under the control of the lysozyme M (LysM) gene promoter in the mice. When DT was administrated to the mice they suffered from acute lung injury and died within 4 days. Immunohistochemical examination revealed that AE2 cells as well as alveolar macrophages were deleted via apoptosis in the mice treated with DT. Consistent with the deletion of AE2 cells, the amount of surfactant proteins in bronchoalveolar lavage fluid was greatly reduced in the DT-treated transgenic mice. When bone marrow from wild-type mice was transplanted into irradiated LysM-DTR mice, the alveolar macrophages became resistant to DT but the mice still suffered from acute lung injury by DT administration. Compared with the mice in which both AE2 cells and macrophages were deleted by DT administration, the DT-treated LysM-DTR mice with DT-resistant macrophages showed less severe lung injury with a reduced amount of hepatocyte growth factor in bronchoalveolar lavage fluid. These results indicate that macrophages play a protective role in noninflammatory lung injury caused by the selective ablation of AE2 cells. 相似文献
105.
Shinji Kawasaki Masahiro Nagasaku Tsuyoshi Mimura Hitomi Katashima Susumu Ijyuin Takumi Satoh Youichi Niimura 《Applied microbiology》2007,73(23):7796-7798
This report investigates the requirement for CO2 for colony formation by Bifidobacterium species in both anoxic and oxic environments. All tested Bifidobacterium species exhibited difficulty in developing colonies in an atmosphere of 100% N2 but developed well when 1% CO2 was present. In the presence of CO2, the oxygen tolerance of the tested species was not improved. In the absence of CO2, only B. boum, a microaerophilic species, could develop colonies under an N2-based 5% O2 atmosphere, indicating that while CO2 is not an essential factor for colony development, both CO2 and O2 have stimulatory effects on B. boum colony development. 相似文献
106.
Enrichment of longevity phenotype in mtDNA haplogroups D4b2b, D4a, and D5 in the Japanese population
Alexe G Fuku N Bilal E Ueno H Nishigaki Y Fujita Y Ito M Arai Y Hirose N Bhanot G Tanaka M 《Human genetics》2007,121(3-4):347-356
We report new results from the re-analysis of 672 complete mitochondrial (mtDNA) genomes of unrelated Japanese individuals
stratified into seven equal sized groups by the phenotypes: diabetic patients, diabetic patients with severe angiopathy, healthy
non-obese young males, obese young males, patients with Alzheimer’s disease, patients with Parkinson’s disease and centenarians.
Each phenotype had 96 samples over 27 known haplogroups: A, B4a, B4b, B4c, B*, B5, D*, F1, F2, M*, M7a, M7b, M8, M9, D4a,
D4b1, D4b2, D4d, D4e, D4g, D4h, D5, G, Z, M*, N9a, and N9b. A t-test comparing the fraction of samples in a haplogroup to healthy young males showed a significant enrichment of haplogroups
D4a, D5, and D4b2 in centenarians. The D4b2 enrichment was limited to a subgroup of 40 of 61 samples which had the synonymous
mutation 9296C > T. We identified this cluster as a distinct haplogroup and labeled it as D4b2b. Using an exhaustive procedure,
we constructed the complete list of “mutation patterns” for centenarians and showed that the most significant patterns were
in D4a, D5, and D4b2b. We argue that if a selection for longevity appeared only once, it was probably an autosomal event which
could be dated to after the appearance of the D mega-group but before the coalescent time of D4a, D5, and D4b2b. Using a simple
procedure, we estimated that this event occurred 24.4 ± 0.9 kYBP.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Gabriela Alexe and Noriyuki Fuku are joint first authors. 相似文献
107.
Ubukata M Takamori H Ohashi M Mitsuhashi S Yamashita K Asada T Nakajima N Matsuura N Tsuruga M Taki K Magae J 《Bioorganic & medicinal chemistry letters》2007,17(17):4767-4770
Mycophenolic acid (MPA), known as an inhibitor of inosine monophosphate dehydrogenase (IMPDH), was found to inhibit the differentiation of 3T3-L1 pre-adipocytes into mature adipocytes. Although the effect of MPA was attributed to inhibition of IMPDH, we uncovered a hidden biological property of MPA as an agonist of peroxisome proliferator activated receptor gamma (PPARgamma). 相似文献
108.
Characterization of the estrogenic activities of zearalenone and zeranol in vivo and in vitro 总被引:1,自引:0,他引:1
Takemura H Shim JY Sayama K Tsubura A Zhu BT Shimoi K 《The Journal of steroid biochemistry and molecular biology》2007,103(2):170-177
In the present study, we compared the estrogenic activity of zearalenone (ZEN) and zeranol (ZOL) by determining their relative receptor binding affinities for human ERalpha and ERbeta and also by determining their uterotropic activity in ovariectomized female mice. ZOL displayed a much higher binding affinity for human ERalpha and ERbeta than ZEN did. The IC(50) values of ZEN and ZOL for binding to human ERalpha were 240.4 and 21.79nM, respectively, and the IC(50) values for binding to ERbeta were 165.7 and 42.76nM, respectively. In ovariectomized female ICR mice, s.c. administration of ZEN at doses >or=2mg/kg/day for 3 consecutive days significantly increased uterine wet weight compared with the control group, and administration of ZOL increased the uterine wet weight at lower doses (>or=0.5mg/kg/day for 3 days). Based on available X-ray crystal structures of human ERalpha and ERbeta, we have also conducted molecular modeling studies to probe the binding characteristics of ZEN and ZOL for human ERalpha and ERbeta. Our data revealed that ZEN and ZOL were able to occupy the active site of the human ERalpha and ERbeta in a strikingly similar manner as 17beta-estradiol, such that the phenolic rings of ZEN and ZOL occupied the same receptor region as occupied by the A-ring of 17beta-estradiol. The primary reason that ZOL and ZEN is less potent than 17beta-estradiol is likely because 17beta-estradiol could bind to the receptor pocket without significantly changing its conformation, while ZOL or ZEN would require considerable conformational alterations upon binding to the estrogen receptors (ERs). 相似文献
109.
Teno N Miyake T Ehara T Irie O Sakaki J Ohmori O Gunji H Matsuura N Masuya K Hitomi Y Nonomura K Horiuchi M Gohda K Iwasaki A Umemura I Tada S Kometani M Iwasaki G Cowan-Jacob SW Missbach M Lattmann R Betschart C 《Bioorganic & medicinal chemistry letters》2007,17(22):6096-6100
Pyrrolopyrimidine, a novel scaffold, allows to adjust interactions within the S3 subsite of cathepsin K. The core intermediate 10 facilitated the P3 optimization and identified highly potent and selective cathepsin K inhibitors 11-20. 相似文献
110.
Fluxomics: mass spectrometry versus quantitative imaging 总被引:1,自引:0,他引:1