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101.
Hattori J Okumura N Yamazaki Y Uchiyama M Hamaguchi M Nishiyama Y Kaneda T 《Microbiology and immunology》2007,51(2):193-200
Several reports have documented a better prognosis for HIV‐1‐infected patients co‐infected with GBV‐C, while other reports have contradicted such findings with the result that this issue remains controversial. We attempted to clarify the complicated status of the effect of GBV‐C co‐infection on HIV‐1‐infected patients. GBV‐C RNA was detected in 37 samples in 182 HIV‐1‐infected patients (20.3%) using RT/nested PCR. Of these, 3 were determined to be GBV‐C genotype 1, 12 were genotype 2, and the remaining 22 were genotype 3. The GBV‐C viral load quantified by real‐time PCR ranged from 7.8 × 103 to 3.3 × 106 copies/ml. Weakly negative correlation was observed between GBV‐C viral load and HIV‐1 viral load in 19 HAART‐naïve patients, indicating that a higher GBV‐C viral load is associated with a greater suppression of HIV‐1 replication. A previously published in vitro study suggested that GBV‐C infection would induce up‐regulation of RANTES, leading to suppression of HIV‐1 replication. However, in our present study, the blood RANTES level was significantly lower in the GBV‐C co‐infected group than in the uninfected group (190–9,959 vs. 264–31,038 pg/ml, P=0.004). Our results suggested that a suppression of HIV‐1 replication by GBV‐C co‐infection is not mediated by up‐regulated RANTES, and thus call for another as yet unknown factor. 相似文献
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104.
Sheliang Wang Toshiaki Ito Masataka Uehara Satoshi Naito Junpei Takano 《Journal of plant research》2015,128(5):863-873
Endomembrane organization is essential for cell physiology. We previously identified an Arabidopsis thaliana mutant in which a plasma membrane (PM) marker GFP-NIP5;1 and trans-Golgi network/early endosome (TGN/EE) markers were accumulated in intracellular aggregates in epidermal cells of the root elongation zone. The mutant was identified as an allele of UDP-glucose epimerase 4 (UGE4)/root hair defective 1/root epidermal bulgar 1, which was previously described as a mutant with swollen root epidermal cells and has an altered sugar composition in cell wall polysaccharides. Importantly, these defects including aggregate formation were restored by supplementation of d-galactose in the medium. These results suggested that UDP-d-galactose synthesis by UGE4 is important for endomembrane organization in addition to cell wall structure. Here, we further investigated the nature of the aggregates using various markers of endomembrane compartments and BOR1-GFP, which traffics from PM to vacuole in response to high-B supply. The markers of multi-vesicular bodies/late endosomes (MVB/LEs) and BOR1-GFP were strongly accumulated in the intracellular aggregates, while those of the endoplasmic reticulum (ER), the vacuolar membrane, and the Golgi were only slightly affected in the uge4 mutant. The abnormal localizations of these markers in the uge4 mutant differed from the effects of inhibitors of actin and microtubule polymerization, although they also affected endomembrane organization. Furthermore, electron microscopy analysis revealed accumulation of abnormal high-electron-density vesicles in elongating epidermal cells. The abnormal vesicles were often associated or interconnected with TGN/EEs and contained ADP-ribosylation factor 1, which is usually localized to the Golgi and the TGN/EEs. On the other hand, structures of the ER, Golgi apparatus, and MVB/LEs were apparently normal in uge4 cells. Together, our data indicate the importance of UDP-d-galactose synthesis by UGE4 for the organization and function of endomembranes, especially TGN/EEs, which are a sorting station of the secretory and vacuolar pathways. 相似文献
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107.
Tabata M Endo R Ito M Ohtsubo Y Kumar A Tsuda M Nagata Y 《Bioscience, biotechnology, and biochemistry》2011,75(3):466-472
A γ-hexachlorocyclohexane (HCH)-degrading bacterium, Sphingomonas sp. MM-1, was isolated from soil contaminated with HCH isomers. Cultivation of MM-1 in the presence of γ-HCH led to the detection of five γ-HCH metabolites, γ-pentachlorocyclohexene, 2,5-dichloro-2,5-cyclohexadiene-1,4-diol, 2,5-dichlorohydroquinone, 1,2,4-trichlorobenzene, and 2,5-dichlorophenol, strongly suggesting that MM-1 has the lin genes for γ-HCH degradation originally identified in the well-studied γ-HCH-degrading strain Sphingobium japonicum UT26. Southern blot, PCR amplification, and sequencing analyses indicated that MM-1 has seven lin genes for the conversion of γ-HCH to β-ketoadipate (six structural genes, linA to linF, and one regulatory gene, linR). MM-1 carried four plasmids, of 200, 50, 40, and 30 kb. Southern blot analysis revealed that all seven lin genes were dispersed across three of the four plasmids, and that IS6100, often found close to the lin genes, was present on all four plasmids. 相似文献
108.
Muthu P Wang L Yuan CC Kazmierczak K Huang W Hernandez OM Kawai M Irving TC Szczesna-Cordary D 《FASEB journal》2011,25(12):4394-4405
The myosin essential light chain (ELC) is a structural component of the actomyosin cross-bridge, but its function is poorly understood, especially the role of the cardiac specific N-terminal extension in modulating actomyosin interaction. Here, we generated transgenic (Tg) mice expressing the A57G (alanine to glycine) mutation in the cardiac ELC known to cause familial hypertrophic cardiomyopathy (FHC). The function of the ELC N-terminal extension was investigated with the Tg-Δ43 mouse model, whose myocardium expresses a truncated ELC. Low-angle X-ray diffraction studies on papillary muscle fibers in rigor revealed a decreased interfilament spacing (≈ 1.5 nm) and no alterations in cross-bridge mass distribution in Tg-A57G mice compared to Tg-WT, expressing the full-length nonmutated ELC. The truncation mutation showed a 1.3-fold increase in I(1,1)/I(1,0), indicating a shift of cross-bridge mass from the thick filament backbone toward the thin filaments. Mechanical studies demonstrated increased stiffness in Tg-A57G muscle fibers compared to Tg-WT or Tg-Δ43. The equilibrium constant for the cross-bridge force generation step was smallest in Tg-Δ43. These results support an important role for the N-terminal ELC extension in prepositioning the cross-bridge for optimal force production. Subtle changes in the ELC sequence were sufficient to alter cross-bridge properties and lead to pathological phenotypes. 相似文献
109.
Shi XL Ge JF Liu BQ Kaiser M Wittlin S Brun R Ihara M 《Bioorganic & medicinal chemistry letters》2011,21(19):5804-5807
A series of 5-phenyliminobenzo[a]phenoxazine derivatives were synthesized. The in vitro antiprotozoal activities were evaluated against Plasmodium falciparum K1, Trypanosoma cruzi, Leishmania donovani and Trypanosoma brucei rhodesiense. N,N-Diethyl-5-((4-methoxyphenyl)imino)-5H-benzo[a]phenoxazin-9-amine shows IC(50)=0.040 μmol L(-1) with a selective index of 1425 against Plasmodium falciparum K1. 相似文献
110.
Takeda K Tasai M Akagi S Watanabe S Oe M Chikuni K Ohnishi-Kameyama M Hanada H Nakamura Y Tagami T Nirasawa K 《Molecular reproduction and development》2011,78(4):263-273
Aberrant reprogramming of donor somatic cell nuclei may result in many severe problems in animal cloning. The inability to establish functional interactions between donor nucleus and recipient mitochondria is also likely responsible for such a developmental deficiency. However, detailed knowledge of protein expression during somatic cell nuclear transfer (SCNT) in cattle is lacking. In the present study, variations in mitochondrial protein levels between SCNT‐derived and control cattle, and from calves derived by artificial insemination were investigated. Mitochondrial fractions were prepared from frozen liver samples and subjected to two‐dimensional (2‐D) fluorescence differential gel electrophoresis (DIGE) using CyDye? dyes. Protein expression changes were confirmed with a volume ratio greater than 2.0 (P < 0.05). 2D‐DIGE analysis revealed differential expression of three proteins for SCNT cattle (n = 4) and seven proteins for SCNT calves (n = 6) compared to controls (P < 0.05). Different protein patterning was observed among SCNT animals even if animals were generated from the same donor cell source. No differences were detected in two of the SCNT cattle. Moreover, there was no novel protein identified in any of the SCNT cattle or calves. In conclusion, variation in mitochondrial protein expression concentrations was observed in non‐viable, neonatal SCNT calves and among SCNT individuals. This result implicates mitochondrial‐related gene expression in early developmental loss of SCNT embryos. Comparative proteomic analysis represents an important tool for further studies on SCNT animals. Mol. Reprod. Dev. 78:263–273, 2011. © 2011 Wiley‐Liss, Inc. 相似文献