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981.
Jung Eun Hwang Joon Ki Hong Ji Hyun Je Kyun Oh Lee Dool Yi Kim Sang Yeol Lee Chae Oh Lim 《Plant cell reports》2009,28(11):1623-1632
Phytocystatins are cysteine proteinase inhibitors in plants that are implicated in the endogenous regulation of protein turnover
and defense mechanisms against insects and pathogens. A cDNA encoding a phytocystatin called AtCYS6 (Arabidopsis thaliana phytocystatin6) has been isolated. We show that AtCYS6 is highly expressed in dry seeds and seedlings and that it also accumulates
in flowers. The persistence of AtCYS6 protein expression in seedlings was promoted by abscisic acid (ABA), a seed germination
and post-germination inhibitory phytohormone. This finding was made in transgenic plants bearing an AtCYS6 promoter–β-glucuronidase (GUS) reporter construct, where we found that expression from the AtCYS6 promoter persisted after ABA treatment but was reduced under control conditions and by gibberellin4+7 (GA4+7) treatment during the germination and post-germinative periods. In addition, constitutive over-expression of AtCYS6 retarded germination and seedling growth, whereas these were enhanced in an AtCYS6 knock-out mutant (cys6-2). Additionally, cysteine proteinase activities stored in seeds were inhibited by AtCYS6 in transgenic Arabidopsis. From these data, we propose that AtCYS6 expression is enhanced by the germination inhibitory phytohormone ABA and that it participates in the control of germination
rate and seedling growth by inhibiting the activity of stored cysteine proteinases. 相似文献
982.
Ramesh P. Thylur Young‐Dae Kim Min‐Sung Kwon Hyun‐Mee Oh Ho‐Keun Kwon Sang‐Hyun Kim Sin‐Hyeog Im Jang‐Soo Chun Zee‐Yong Park Chang‐Duk Jun 《Journal of cellular biochemistry》2009,108(3):705-715
Swiprosin‐1 exhibits the highest expression in CD8+ T cells and immature B cells and has been thought to play a role in lymphocyte physiology. Here we report that swiprosin‐1 is also expressed in mast cells and up‐regulated in both in vitro cultured mast cells by phorbol ester and in vivo model tissues of passive cutaneous anaphylaxis and atopic dermatitis. Targeted inhibition of the specific protein kinase C (PKC) isotypes by siRNA revealed that PKC‐βI/η are involved in the expression of swiprosin‐1 in the human mast cell line HMC‐1. In contrast, down‐regulation of swiprosin‐1 by A23187 or ionomycin suggests that calcium‐signaling plays a negative role. The ectopic expression of swiprosin‐1 augmented PMA/A23187‐induced NF‐κB promoter activity, and resulted in increased expression of cytokines. Moreover, knock‐down of swiprosin‐1 attenuated PMA/A23187‐induced cytokine expression. Collectively, these results suggest that swiprosin‐1 is a PKC‐βI/η‐inducible gene and it modulates mast cell activation through NF‐κB‐dependent pathway. J. Cell. Biochem. 108: 705–715, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
983.
The role of extracellular signal-regulated kinase (ERK) signaling in skeletal myogenesis has been reported to be both stimulatory and inhibitory. We propose that this discrepancy may arise from the stage-specific, different roles of mitogen-activated protein kinase kinase 1 (MEK1). We found that the phosphorylated MEK1 level of differentiating C2C12 cells was low on day 1 (early-stage) and reached a maximum on days 2–3 (mid-stage). Cells treated at early stage with the MEK-specific inhibitors, PD184352 and U0126, reduced both the MHC protein level and MCK promoter activity, demonstrating that high MEK1 activity at the mid-stage is required for myogenic differentiation. In contrast, treatment with the ERK-specific inhibitors, FR180204 and ERK inhibitor I, had no effect. However, because the sustained overexpression of constitutively active MEK1 inhibits myogenic differentiation, we further analyzed the stage-specific role of MEK1 using the Tet-Off expression system. The results demonstrated that myogenic differentiation was inhibited if active MEK1 expression was induced earlier than day 1 in differentiation condition, but stimulated if induced after that, demonstrating that activated MEK1 plays differential roles depending on activation time. In addition, the induction of active MEK1 at 12 h enhanced the Id2 protein level, while the induction at 36 h resulted in reduction. Thus, MEK1 plays stage-specific and contrary roles in myogenesis, and MEK1 activated at the mid-stage promotes muscle differentiation independent of ERK. 相似文献
984.
Hong Ma Young-Jun Jo Yuan Ma Jin-Tae Hong Byoung-Mog Kwon Ki-Wan Oh 《Phytomedicine》2009,16(4):308-313
This study aimed to investigate the effects of obovatol isolated from Magnolia obovata on pentobarbital-induced sleeping behaviors and to determine whether these effects were mediated by GABAA receptors/chloride channel activation, using a western blot technique and Cl? sensitive fluorescence probe. GABAA receptors subunits expression and chloride influx were investigated in cultured cerebellar granule cells. Obovatol (0.05, 0.1, and 0.2 mg/kg) prolonged the sleeping time induced by pentobarbital (42 mg/kg). In addition, obovatol (20 and 50 μM) significantly increased Cl? influx in the primary cultured cerebellar granule cells. Moreover, obovatol increased the expression of GABAA receptor α-, β-, and γ-subunits. However, it had no effect on the abundance of the expression of glutamic acid decarboxylase (GAD), suggesting that obovatol might not activate GAD. These results suggest that obovatol potentiates pentobarbital-induced sleeping time through the GABAA receptors/chloride channel activation. 相似文献
985.
986.
A small-silo study was conducted to develop an effective ensiling storage method for the use of cotton waste-based spent mushroom substrate (SMS) as an animal feed. The SMS was ensiled with 5% molasses (DM basis), 0.5% (v/w) lactic acid bacteria (LAB, Lactobacillus plantarum) inoculant or 0.5% (v/w) yeast (Saccharomyces cerevisiae) inoculant. The treatments included 100% SMS (control), 95% SMS+5% molasses (T1), 95% SMS+5% molasses+0.5% LAB (T2) and 95% SMS+5% molasses+5% LAB+0.5% yeast (T3). The treatments were ensiled for 10. Change in chemical compositions was little (P>0.05) according to the ensiling process and treatments. Compared with those before ensiling, 100% SMS (control) after ensiling showed unstable fermentative properties with high pH (5.2) and little lactic acid production. Compared with the ensiled control, treatments (T1, T2 and T3) resulted in decreased pH, 18-20 times higher concentrations of lactic acid, and greater populations of total bacteria (P<0.07), LAB and yeast (P<0.07). The addition of 5% molasses, 0.5% LAB and 0.5% yeast (T3) to the SMS resulted in the lowest pH (4.25) and the greatest microbial populations. Treatment T3 was selected for a large scale silo study which was ensiled for 10, 20 and 30 d. As in the small-silo study, the T3 treatment showed favorable fermentative and microbial parameters, compared with the control, by decreasing pH and increasing lactic acid concentrations, LAB and yeast populations. The minimum ensiling period was 20 d, when pH was reasonably low and LAB and yeast populations were greatest. In conclusion, molasses and microbial inoculation improved silage quality of SMS. 相似文献
987.
Joseph P. Marino Lara S. Kallander Chun Ma Hye-Ja Oh Dennis Lee Dimitri E. Gaitanopoulos John A. Krawiec Derek J. Parks Christine L. Webb Kelly Ziegler Michael Jaye Scott K. Thompson 《Bioorganic & medicinal chemistry letters》2009,19(19):5617-5621
The liver X receptors (LXR) play a key role in cholesterol homeostasis and lipid metabolism. SAR studies around tertiary-amine lead molecule 2, an LXR full agonist, revealed that steric and conformational changes to the acetic acid and propanolamine groups produce dramatic effects on agonist efficacy and potency. The new analogs possess good functional activity, demonstrating the ability to upregulate LXR target genes, as well as promote cholesterol efflux in macrophages. 相似文献
988.
Ibrahim M. El-Deeb Byung Sun Park Su Jin Jung Kyung Ho Yoo Chang-Hyun Oh Seung Joo Cho Dong Keun Han Jae Yeol Lee So Ha Lee 《Bioorganic & medicinal chemistry letters》2009,19(19):5622-5626
A series of rationally designed ROS1 tyrosine kinase inhibitors was synthesized and screened. Compound 12b has showed good potency with IC50 value of 209 nM, which is comparable with that of the reference lead compound 1. Molecular modeling studies have been performed, that is, a homology model for ROS1 was built, and the screened inhibitors were docked into its major identified binding site. The docked poses along with the activity data have revealed a group of the essential features for activity. Overall, simplification of the lead compound 1 into compound 12b has maintained the activity, while facilitated the synthetic advantages. A molecular interaction model for ROS1 kinase and inhibitors has been proposed. 相似文献
989.
Changon Seo Jae Hak Sohn Hyuncheol Oh Bo Yeon Kim Jong Seog Ahn 《Bioorganic & medicinal chemistry letters》2009,19(21):6095-6097
In the course of bioassay-guided study on the EtOAc extract of a culture broth of the marine-derived fungus Cosmospora sp. SF-5060, aquastatin A (1) was isolated as a protein tyrosine phosphatase 1B (PTP1B) inhibitory component produced by the fungus. The compound was isolated by various chromatographic methods, and the structure was determined mainly by analysis of NMR spectroscopic data. Compound 1 exhibited potent inhibitory activity against PTP1B with IC50 value of 0.19 μM, and the kinetic analyses of PTP1B inhibition by compound 1 suggested that the compound is inhibiting PTP1B activity in a competitive manner. Aquastatin A (1) also showed modest but selective inhibitory activity toward PTP1B over other protein tyrosine phosphatases, such as TCPTP, SHP-2, LAR, and CD45. In addition, the result of hydrolyzing aquastatin A (1) suggested that the dihydroxypentadecyl benzoic acid moiety in the molecule is responsible for the inhibitory activity. 相似文献
990.
Sang-Hyun Han In-Cheol Cho Jin-Hyoung Kim Moon-Suck Ko Ha-Yeon Jeong Hong-Shik Oh Sung-Soo Lee 《Genes & genomics.》2009,31(1):35-41
The growth hormone receptor (GHR) is a membrane transmitter for the growth hormone signal transduction pathway that regulates various metabolic activities, including cell growth and expressions of cytokine genes. The presence or absence of a genetic polymorphism for the LINE-1 retroposon in the PI promoter, which specifically regulates theGHR gene expression in the liver, was screened by a novel detection method and examined for its relationships with carcass traits in Hanwoo cattle. Han woo cattle had taurine type LINE-1 present (alleleI) as well as incidine type LINE-1 absent (alleleA) promoter sequences. Three genotypes,I/I, I/A andA/A, showed frequencies of 49.1, 36.7 and 14.2%, respectively. The effects of allele A were significant on mean differences for final weight, eye muscle area, marbling score and fat color (p<0.05), but not for carcass weight, backfat thickness, final meat quality grade or meat color (p>0.05). Most 30-month old Hanwoo steers bearing the LINE-1 absent promoter had whiter fat color, heavier live weight and higher marbling score, reflecting intramuscular fat deposition inM. longissimus dorsi, compared to animals bearing a LINE-1 present promoter. This suggests that aGHR polymorphism could be a potential genetic marker for improving beef production of Hanwoo cattle. 相似文献