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941.
Gyeongwha Kim Younghyurk Lee Eun Young Jeong Soonwoong Jung Hyeonwi Son Dong Hoon Lee Gu Seob Roh Sang Soo Kang Gyeong Jae Cho Wan Sung Choi Hyun Joon Kim 《Molecules and cells》2010,30(2):161-165
Regulator of G-protein signaling (RGS) proteins play an important role in G-protein coupled receptor (GPCR) signaling and the activity of some GPCRs is modulated via RGS protein levels during stress response. The aim of this study was to investigate changes in RGS protein mRNA expressions in the mouse brain after 2h restraint stress. The mRNA level of 19 RGS proteins was analyzed using real-time PCR in six brain regions, which included the prefrontal cortex, amygdala, hippocampus, hypothalamus, striatum, and pituitary gland, from control and stressed mouse. We found that the level of mRNA of each RGS varied according to brain region and that two to eight RGS proteins exhibited changes in mRNA levels in each brain region by restraint stress. It was also revealed that RGS4 protein amount was consistent with mRNA level, indicating RGS4 protein may have regulatory roles in the acute stress response. 相似文献
942.
Monika Joon Shipra Bhatia Rashmi Pasricha Mridula Bose Vani Brahmachari 《BMC microbiology》2010,10(1):128
Background
The mce operons play an important role in the entry of M. tuberculosis into macrophages and non-phagocytic cells. Their non-redundant function as well as complex regulation is implied by the phenotype of mce mutants. Recently, mce1 operon was found to extend over 13 genes, fadD5 (Rv0166) being the first gene of the operon. The presence of a non-coding sequence of 200 base pairs between Rv0166 and Rv0167 is peculiar to mce1 among the four mce operons of M.tuberculosis. We have examined the function of this region. 相似文献943.
Young Sun Oh Dae Gyu Kim Gyuyoup Kim Eung‐Chil Choi Brian K. Kennedy Yousin Suh Bum Joon Park Sunghoon Kim 《Aging cell》2010,9(5):810-822
Although AIMP3/p18 is normally associated with the macromolecular tRNA synthetase complex, recent reports have revealed a new role of AIMP3 in tumor suppression. In this study, we generated a transgenic mouse that overexpresses AIMP3 and characterized the associated phenotype in vivo and in vitro. Surprisingly, the AIMP3 transgenic mouse exhibited a progeroid phenotype, and the cells that overexpressed AIMP3 showed accelerated senescence and defects in nuclear morphology. We found that overexpression of AIMP3 resulted in proteasome‐dependent degradation of mature lamin A, but not of lamin C, prelamin A, or progerin. The resulting imbalance in the protein levels of lamin A isoforms, namely altered stoichiometry of prelamin A and progerin to lamin A, appeared to be responsible for a phenotype that resembled progeria. An increase in the level of endogenous AIMP3 has been observed in aged human tissues and cells. The findings in this report suggest that AIMP3 is a specific regulator of mature lamin A and imply that enhanced expression of AIMP3 might be a factor driving cellular and/or organismal aging. 相似文献
944.
We investigated the thermal effects on heart rate, hemodynamics, and response of vitelline arteries of stage-18 chicken embryos. Heart rate was monitored by a high-speed imaging method, while hemodynamic quantities were evaluated using a particle image velocimetry (PIV) technique. Experiments were carried out at seven different temperatures (36–42 °C with 1 °C interval) after 1 h of incubation to stabilize the heart rate. The heart rate increased in a linear manner (r=0.992). Due to the increased cardiac output (or heart rate), the hemodynamic quantities such as mean velocity (Umean), velocity fluctuation (Ufluc), and peak velocity (Upeak) also increased with respect to the Womersley number (Ω) in the manner r=0.599, 0.693, and 0.725, respectively. This indicates that the mechanical force exerting on the vessel walls increases. However, the active response (or regulation) of the vitelline arteries was not observed in this study. 相似文献
945.
Song JY Jeong H Yu DS Fischbach MA Park HS Kim JJ Seo JS Jensen SE Oh TK Lee KJ Kim JF 《Journal of bacteriology》2010,192(23):6317-6318
Streptomyces clavuligerus is an important industrial strain that produces a number of antibiotics, including clavulanic acid and cephamycin C. A high-quality draft genome sequence of the S. clavuligerus NRRL 3585 strain was produced by employing a hybrid approach that involved Sanger sequencing, Roche/454 pyrosequencing, optical mapping, and partial finishing. Its genome, comprising four linear replicons, one chromosome, and four plasmids, carries numerous sets of genes involved in the biosynthesis of secondary metabolites, including a variety of antibiotics. 相似文献
946.
Hannah S. Rhee Joseph F.Y. Hoh 《The journal of histochemistry and cytochemistry》2010,58(12):1057-1065
This work uses cross-innervation of respiratory muscles of different developmental origins to probe myogenic and neurogenic mechanisms regulating their fiber types. The thyroarytenoid (TA) originates from the sixth branchial arch, whereas the sternohyoid (SH) is derived from somitic mesoderm. Immunohistochemical analysis using highly specific monoclonal antibodies to myosin heavy chain (MyHC) isoforms reveals that normal rat SH comprises slow, 2a, 2x, and 2b fibers, as in limb fast muscles, whereas the external division of the TA has only 2b/eo fibers coexpressing 2B and extraocular (EO) MyHCs. Twelve weeks after cross-innervation with the recurrent laryngeal nerve, the SH retained slow and 2a fibers, greatly increased the proportion of 2x fibers, and their 2b fibers failed to express EO MyHC. In the cross-innervated TA, the SH nerve failed to induce slow and 2A MyHC expression and failed to suppress EO MyHC expression in 2b/eo fibers. However, 2x fibers amounting to 4.2% appeared de novo in the external division of the TA. We conclude that although MyHC gene expression in these muscles can be modulated by neural activity, the patterns of response to altered innervation are largely myogenically determined, thus supporting the idea that SH and TA differ in muscle allotype. (J Histochem Cytochem 58:1057–1065, 2010) 相似文献
947.
Rad17 is critical for the ATR-dependent activation of Chk1 during checkpoint responses. It is known that Rad17 loads the Rad9-Hus1-Rad1 (9-1-1) complex onto DNA. We show that Rad17 also mediates the interaction of 9-1-1 with the ATR-activating protein TopBP1 in Xenopus egg extracts. Studies with Rad17 mutants indicate that binding of ATP to Rad17 is essential for the association of 9-1-1 and TopBP1. Furthermore, hydrolysis of ATP by Rad17 is necessary for the loading of 9-1-1 onto DNA and the elevated, checkpoint-dependent accumulation of TopBP1 on chromatin. Significantly, a mutant 9-1-1 complex that cannot bind TopBP1 has a normal capacity to promote elevated accumulation of TopBP1 on chromatin. Taken together, we propose the following mechanism. First, Rad17 loads 9-1-1 onto DNA. Second, TopBP1 accumulates on chromatin in a manner that depends on both Rad17 and 9-1-1. Finally, 9-1-1 and TopBP1 dock in a Rad17-dependent manner before activation of Chk1. 相似文献
948.
Diversity of endophytic bacteria in ginseng and their potential for plant growth promotion 总被引:1,自引:0,他引:1
Endophytic bacteria have been found in virtually every plant studied, where they colonize the internal tissues of their host
plant and can form a range of different beneficial relationships. The diversity of bacterial endophytes associated with ginseng
plants of varying age levels in Korea was investigated. Fifty-one colonies were isolated from the interior of ginseng stems.
Although a mixed composition of endophyte communities was recovered from ginseng based on the results of 16S rDNA analysis,
bacteria of the genus Bacillus and Staphylococcus dominated in 1-year-old and 4-year-old plants, respectively. Phylogenetic analysis revealed four clusters: Firmicutes, Actinobacteria, α-Proteobacteria, and γ-Proteobacteria, with Firmicutes being predominant. To evaluate the plant growth promoting activities, 18 representative isolates were selected. Amplification
of nifH gene confirmed the presence of diazotrophy in only two isolates. Half of the isolates solubilized mineral phosphate. Except
four, all the other endophytic isolates produced significant amounts of indole acetic acid in nutrient broth. Iron sequestering
siderophore production was detected in seven isolates. Isolates E-I-3 (Bacillus megaterium), E-I-4 (Micrococcus luteus), E-I-8 (B. cereus), and E-I-20 (Lysinibacillus fusiformis) were positive for most of the plant growth promoting traits, indicating their role in growth promotion of ginseng. 相似文献
949.
Deok Ho Kwon Deok Young Song Soyoung Kang Jeong Joon Ahn Joon-Ho Lee Byeong Ryeol Choi Si Woo Lee Jeong-Han Kim Si Hyeock Lee 《Journal of Asia》2010,13(4):333-337
To develop a less technique-dependent bioassay technique that can be conveniently used by practitioners or farmers in the field for the monitoring of acaricide resistance of the two-spotted spider mite, Tetranychus urticae Koch, a residual contact vial (RCV) method was established using a 5-ml glass vial coated with acaricides. The RCV bioassay procedures were optimized by using abamectin and tebufenpyrad, two widely used acaricides. The diagnostic concentrations causing 100% mortality within 8 h post-treatment in a susceptible strain of T. urticae was set at 30 and 60 ppm for abamectin and tebufenpyrad, respectively. The vial-coated pesticides were stable at least one year when stored at ? 20 °C as determined by HPLC. There was no significant difference in the bioassay results in repeated RCV bioassay by three different experimenters, indicating its high reproducibility and reliability. RCV-based resistance monitoring of 15 field populations of mites revealed that abamectin resistance begins to spread but tebufenpyrad resistance is already prevalent in Korea. The RCV diagnostic kit, when used by practitioners or farmers on site, should provide crucial information for the selection of most suitable acaricides for different field populations of T. urticae. 相似文献
950.
Myung Jin Koh Hyun Sung Lee Jee Eun Rhee Sang Ho Choi 《Journal of microbiology (Seoul, Korea)》2010,48(1):129-133
Expression of ahpC2 encoding an alkyl hydroperoxide reductase of Vibrio vulnificus, a foodborne pathogen, was incrementally induced depending on NaCl concentrations in the culture. Growth of the ahpC2 mutant was significantly impaired with longer lag phase and lower growth rate when cultured under high salinity. ROS was
accumulated in V. vulnificus cells when stressed by exposure to high salinity, and the ahpC2 mutant accumulated higher level of ROS as compared with the parental wild type. Consequently, the combined results suggest
that AhpC2 contributes to the growth of V. vulnificus under high salinity by scavenging ROS in cells. 相似文献