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71.
Park JH Lee SY Kim WY Jung YJ Chae HB Jung HS Kang CH Shin MR Kim SY Su'udi M Yun DJ Lee KO Kim MG Lee SY 《The New phytologist》2011,191(3):692-705
? This study reports that Arabidopsis thaliana protein serine/threonine phosphatase 5 (AtPP5) plays a pivotal role in heat stress resistance. A high-molecular-weight (HMW) form of AtPP5 was isolated from heat-treated A. thaliana suspension cells. AtPP5 performs multiple functions, acting as a protein phosphatase, foldase chaperone, and holdase chaperone. The enzymatic activities of this versatile protein are closely associated with its oligomeric status, ranging from low oligomeric protein species to HMW complexes. ? The phosphatase and foldase chaperone functions of AtPP5 are associated primarily with the low-molecular-weight (LMW) form, whereas the HMW form exhibits holdase chaperone activity. Transgenic over-expression of AtPP5 conferred enhanced heat shock resistance to wild-type A. thaliana and a T-DNA insertion knock-out mutant was defective in acquired thermotolerance. A recombinant phosphatase mutant (H290N) showed markedly increased holdase chaperone activity. ? In addition, enhanced thermotolerance was observed in transgenic plants over-expressing H290N, which suggests that the holdase chaperone activity of AtPP5 is primarily responsible for AtPP5-mediated thermotolerance. ? Collectively, the results from this study provide the first evidence that AtPP5 performs multiple enzymatic activities that are mediated by conformational changes induced by heat-shock stress. 相似文献
72.
Adaptation of DNA melting analysis for polymorphic single nucleotides (SNPs) genotyping using an unlabeled oligonucleotide probe for polymorphic DNAs under the presence of fluorescent DNA binding dye necessitates a reaction condition where the probe efficiently associates with a target strand that is PCR amplified. We present experimental evidence that application of an unlabeled probe to a dilute PCR amplicon provides a condition such that the fluorescent signals gained subsequently by probe melting are sufficient to discriminate allelic identities. This approach is best exploited by adapting the multiplexing PCR technique in order to cover multiple SNPs for given samples. 3′-end modification of the probe is unnecessary as the amplicon dilution step provides a way of inactivating the polymerase through divalent cation chelation. With the use of low-cost reagents and ordinary laboratory equipment, this method offers a rapid, simple and cost-efficient way of SNP genotyping. 相似文献
73.
Pitna Kim Jin Hee Park Chang Soon Choi Inah Choi So Hyun Joo Min Kyoung Kim Soo Young Kim Ki Chan Kim Seung Hwa Park Kyoung Ja Kwon Jongmin Lee Seol-Heui Han Jong Hoon Ryu Jae Hoon Cheong Jung Yeol Han Ki Narm Ko Chan Young Shin 《Neurochemical research》2013,38(3):620-631
Prenatal exposure to alcohol has consistently been associated with adverse effects on neurodevelopment, which is collectively called fetal alcohol spectrum disorder (FASD). Increasing evidence suggest that prenatal exposure to alcohol increases the risk of developing attention deficit/hyperactivity disorder-like behavior in human. In this study, we investigated the behavioral effects of prenatal exposure to EtOH in offspring mice and rats focusing on hyperactivity and impulsivity. We also examined changes in dopamine transporter and MeCP2 expression, which may underlie as a key neurobiological and epigenetic determinant in FASD and hyperactive, inattentive and impulsive behaviors. Mouse or rat offspring born from dam exposed to alcohol during pregnancy (EtOH group) showed hyper locomotive activity, attention deficit and impulsivity. EtOH group also showed increased dopamine transporter and norepinephrine transporter level compared to control group in the prefrontal cortex and striatum. Prenatal exposure to EtOH also significantly decreased the expression of MeCP2 in both prefrontal cortex and striatum. These results suggest that prenatal exposure to EtOH induces hyperactive, inattentive and impulsive behaviors in rodent offspring that might be related to global epigenetic changes as well as aberration in catecholamine neurotransmitter transporter system. 相似文献
74.
Hee Jin Park Hyeong Cheol Park Sang Yeol Lee Hans J. Bohnert Dae-Jin Yun 《Journal of Plant Biology》2011,54(5):275-285
Posttranslational modifications of proteins by small polypeptides including ubiquitination, neddylation (related to ubiquitin
(RUB) conjugation), and sumoylation are implicated in plant growth and development, and they regulate protein degradation,
location, and interaction with other proteins. Ubiquitination mediates the selective degradation of proteins by the ubiquitin
(Ub)/proteasome pathway. The ubiquitin-like protein RUB is conjugated to cullins, which are part of a ubiquitin E3 ligase
complex that is involved in auxin hormonal signaling. Sumoylation, by contrast, is known for its involvement in guiding protein
interactions related to abiotic and biotic stresses and in the regulation of flowering time. ATG8/ATG12-mediated autophagy
influences degradation and recycling of cellular components. Other ubiquitin-like modifiers (ULPs) such as homology to Ub-1,
ubiquitin-fold modifier 1, and membrane-anchored Ub-fold are also found in Arabidopsis. ULPs share similar three-dimensional structures and a conjugation system, including E1 activating enzymes, E2 conjugation
enzymes, and E3 ligases, as well as proteases for deconjugation and recycling of the tags. However, each of the ULP posttranslational
modifications possesses its own specific enzymes and modifies its specific targets selectively. This review discusses recent
findings on ubiquitination and ubiquitin-like modifier processes and their roles in the posttranslational modification of
proteins in Arabidopsis. 相似文献
75.
Effect of Dislocation Arrays at Grain Boundaries on Electronic Transport Properties of Bismuth Antimony Telluride: Unified Strategy for High Thermoelectric Performance 下载免费PDF全文
Jae‐Yeol Hwang Jungwon Kim Hyun‐Sik Kim Sang‐Il Kim Kyu Hyoung Lee Sung Wng Kim 《Liver Transplantation》2018,8(20)
Taming electronic and thermal transport properties is the ultimate goal in the quest to achieve unprecedentedly high performance in thermoelectric (TE) materials. Most state‐of‐the‐art TE materials are inherently narrow bandgap semiconductors, which have an inevitable contribution from minority carriers, concurrently decreasing Seebeck coefficient and increasing thermal conductivity. Nevertheless, the restraint control of minority carrier transport is seldom considered as a key element to enhance the TE figure of merit (zT). Herein, it is verified that the localized dislocation arrays at grain boundaries enable the suppression of minority carrier contribution to electronic transport properties, resulting in an increase of the Seebeck coefficient and the carrier mobility in bismuth antimony tellurides. It is also suggested that the suppression of minority carriers via the generation of dislocation arrays at grain boundaries is an effective and noninvasive strategy to optimize overall electronic transport properties without sacrificing predominant characteristics of majority carriers in TE materials. 相似文献
76.
Huynh Nhu Mai Naveen Sharma Eun-Joo Shin Bao Trong Nguyen Ji Hoon Jeong Choon-Gon Jang Eun-Hee Cho Seung Yeol Nah Nam Hun Kim Toshitaka Nabeshima Hyoung-Chun Kim 《Neurochemical research》2018,43(5):1118-1135
Evidence indicates that stress conditions might lead to drug dependence. Recently, we have demonstrated that exposure to far infrared ray (FIR) attenuates acute restraint stress via induction of glutathione peroxidase-1 (GPx-1) gene. We investigated whether FIR affects methamphetamine (MA)-induced behavioral sensitization and whether FIR-mediated pharmacological activity requires interaction between dopamine receptor and GPx-1 gene. We observed that MA treatment significantly increased GPx-1 expression in the striatum of wild-type (WT) mice. Interestingly, exposure to FIR potentiated MA-induced increase in GPx-1 expression. This phenomenon was also observed in animals receiving MA with dopamine D1 receptor antagonist SCH23390. However, dopamine D2 receptor antagonist sulpiride did not affect MA-induced GPx-1 expression. FIR exposure or SCH23390, but not sulpiride, significantly attenuated MA-induced behavioral sensitization. Exposure to FIR significantly attenuated MA-induced dopamine D1 receptor expression, c-Fos induction and oxidative burdens. FIR-mediated antioxidant effects were also more pronounced in mitochondrial- than cytosolic-fraction. In addition, FIR significantly attenuated against MA-induced changes in mitochondrial superoxide dismutase and mitochondrial GPx activities, mitochondrial transmembrane potential, intramitochondrial Ca2+ level, mitochondrial complex-I activity, and mitochondrial oxidative burdens. The attenuation by FIR was paralleled that by SCH23390. Effects of FIR or SCH23390 were more sensitive to GPx-1 KO than WT mice, while SCH23390 treatment did not exhibit any additive effects on the protective activity mediated by FIR, indicating that dopamine D1 receptor constitutes a molecular target of FIR. Our result suggests that exposure to FIR ameliorates MA-induced behavioral sensitization via possible interaction between dopamine D1 receptor and GPx-1 gene. 相似文献
77.
The use of biodegradable polymers is one of the key solution to environmental problems and the development of biocompatible
material. The impact of such a large commercial opportunity is one of the primary reasons for much interest in the field of
microbial polyester, polyhydroxyalkanoic acid (PHA). Its valuable properties of biodegradability, biocompatibility and thermoplasticity
have attracted considerable commercial interest, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] has been
launched as the first market product. Recent advances in molecular genetics and microbial physiology of PHA biosynthesis have
been uncovering the biosynthetic mechanics at molecular level, and extensive efforts for the developments of practical applications
and cost-effective mass production of PHA will profell the commercialization of PHA towards the commodity market for biodegradable
plastics. The biosynthesis of new members of PHA family with new monomer or unusual composition will also lead to the biotechnological
production of tailor-made biopolymer for various applications. 相似文献
78.
The methanolysis products of polyhydroxyalkanoic acids (PHAs) containing 4-hydroxybutyric acid (4HB), 4-hydroxyvaleric acid (4HV), and 4-hydroxyhexanoic acid (4HHx), when analyzed by GC-MS, showed two major chromatographic peaks with characteristic retention times of each methyl ester of 4-hydroxyalkanoic acid and the corresponding g-lactone (-butyrolactone, -valerolactone, -caprolactone, respectively). The method and results of GC-MS could be incorporated into an efficient screening procedure for isolation of bacterial strains which could accumulate a PHA containing 4-hydroxyalkanoic acid as the principal monomer from structurally related carbon substrates. 相似文献
79.
Hyuckjin Kwon Mingshou Lu Eun Yeol Lee Jinwon Lee 《Biotechnology and Bioprocess Engineering》2014,19(1):143-149
This study explored efficient methods of harvesting the Tetraselmis sp. KCTC12236BP using flocculation and dissolved air flotation. Concentration ranges of flocculation agents were optimized using jar tests (batch flocculation experiments) using inorganic (aluminum sulfate, ferric sulfate) and organic (chitosan) flocculants in a pH range of 4 ~ 10. The optimal dosage and pH level were 1.2 g/L and pH 5 ~ 6 for aluminum sulfate, 0.7 g/L and pH 4 ~ 8 for ferric sulfate, and 5.0 mg/mL and pH 7 ~ 8 for chitosan. The highest harvesting efficiency achieved with each of the four compounds was 85.6, 92.6, 93, and 91.3%, respectively. 相似文献
80.
Acinetobacter baumannii is a Gram-negative bacterium causing nosocomial infections worldwide. To gain quick insight into the molecular basis of biofilm formation in A. baumannii, we determined the complete genome sequence of A. baumannii strain 1656-2, which forms sturdy biofilm and is resistant to multiple drugs. 相似文献