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Yann Aubert Louis-Jérome Leba Cécilia Cheval Benoit Ranty Alain Vavasseur Didier Aldon Jean-Philippe Galaud 《Plant signaling & behavior》2011,6(4):538-540
The RD20 gene encodes a member of the caleosin family, which is primarily known to function in the mobilization of seed storage lipids during germination. In contrast to other caleosins, RD20 expression is early-induced by water deficit conditions and we recently provided genetic evidence for its positive role in drought tolerance in Arabidopsis. RD20 is also responsive to pathogen infection and is constitutively expressed in diverse tissues and organs during development suggesting additional roles for this caleosin. This addendum describes further exploration of phenotypic alterations in T-DNA insertional rd20 mutant and knock-out complemented transgenic plants in the context of early development and susceptibility to a phytopathogenic bacteria. We show that the RD20 gene is involved in ABA-mediated inhibition of germination and does not play a significant role in plant defense against Pseudomonas syringae.Key words: ABA, Arabidopsis thaliana, biotic stress, caleosin, germination, RD20 相似文献
143.
Tomàs Pinós Mario Marotta Eduard Gallardo Isabel Illa Jorge Díaz-Manera Emiliano Gonzalez-Vioque Elena García-Arumí Antoni L. Andreu Ramon Martí 《Mitochondrion》2011,11(1):228-233
We report a heteroplasmic novel mutation m.5636T>C in the mt-tRNAAla in a patient with bilateral ptosis and ophthalmoparesis in whom a muscle biopsy showed cytochrome c oxdidase (COX) negative and ragged red fibers. Using laser capture microdissection we have isolated COX negative fibers and COX positive fibers from the muscle of the patient and determined that the mutation load was clearly increased in COX negative muscle fibers. Additionally, the mutated m.5636T nucleotide is conserved in all the mammal and non-mammal species analyzed and might be structurally relevant as it is located in a position involved in the formation of tertiary structure of canonical mitochondrial tRNAs. 相似文献
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Ji H Li J Liu P 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2011,159(1):49-56
To determine the effects of n-3 highly unsaturated fatty acids (HUFAs) in grass carp (Ctenopharyngodon idellus), a 75-day feeding experiment was conducted using five isonitrogenous and isoenergetic semi-purified diets containing 0% (control), 0.26%, 0.52%, 0.83% or 1.13% n-3 HUFAs. Weight gain, specific growth rate, feed efficiency and protein efficiency increased by increasing the dietary HUFAs content from 0% to 0.52%, and declined thereafter. Intraperitoneal fat content and the hepatopancreatic lipid levels were lowest in the 0.52% group. The tissue fatty acid level was well correlated with dietary HUFAs content. Hepatic lipoprotein lipase (LPL) activity was significantly higher in the 0.52% group, while that of malate dehydrogenase (MDH) was stable in the 0-0.52% groups, and was significantly lower in the 1.13% group. Superoxide dismutase (SOD) activity increased significantly with increasing dietary HUFAs content, consistent with the level of malondialdehyde (MDA). Hepatic mRNA expression of peroxisome proliferator-activated receptor-α (PPAR-α) was greatest in the 0.83% group and that of the LPL gene increased with increasing dietary HUFAs content up to 0.83%. These results indicate that adequate dietary HUFAs supplementation significantly promotes growth performance and lipid metabolism in freshwater fish grass carp. However, excess HUFAs fortification may exert adverse effects, which might be due to oxidative stress. 相似文献
146.
Mateescu B Batista L Cardon M Gruosso T de Feraudy Y Mariani O Nicolas A Meyniel JP Cottu P Sastre-Garau X Mechta-Grigoriou F 《Nature medicine》2011,17(12):1627-1635
Although there is evidence that redox regulation has an essential role in malignancies, its impact on tumor prognosis remains unclear. Here we show crosstalk between oxidative stress and the miR-200 family of microRNAs that affects tumorigenesis and chemosensitivity. miR-141 and miR-200a target p38α and modulate the oxidative stress response. Enhanced expression of these microRNAs mimics p38α deficiency and increases tumor growth in mouse models, but it also improves the response to chemotherapeutic agents. High-grade human ovarian adenocarcinomas that accumulate miR-200a have low concentrations of p38α and an associated oxidative stress signature. The miR200a-dependent stress signature correlates with improved survival of patients in response to treatment. Therefore, the role of miR-200a in stress could be a predictive marker for clinical outcome in ovarian cancer. In addition, although oxidative stress promotes tumor growth, it also sensitizes tumors to treatment, which could account for the limited success of antioxidants in clinical trials. 相似文献
147.
Bayer M Hellio C Maréchal JP Frank W Lin W Weber H Proksch P 《Marine biotechnology (New York, N.Y.)》2011,13(6):1148-1158
Synthetically prepared congeners of sponge-derived bastadin derivatives such as 5,5′-dibromohemibastadin-1 (DBHB) that suppress
the settling of barnacle larvae were identified in this study as strong inhibitors of blue mussel phenoloxidase that is involved
in the firm attachment of mussels to a given substrate. The IC50 value of DBHB as the most active enzyme inhibitor encountered in this study amounts to 0.84 μM. Inhibition of phenoloxidase
by DBHB is likely due to complexation of copper(II) ions from the catalytic centre of the enzyme by the α-oxo-oxime moiety
of the compound as shown here for the first time by structure activity studies and by X-ray structure determination of a copper(II)
complex of DBHB. 相似文献
148.
目的:建立焦磷酸测序技术检测拉米夫定和阿德福韦酯治疗乙肝所致乙肝病毒基因耐药突变的定量检测方法,为临床乙肝耐药诊断和治疗提供依据。方法:针对乙肝病毒DNA聚合酶基因序列上4个常见基因突变位点的6种突变形式,分别克隆构建野生型和突变型质粒作为标准品,应用生物信息学手段设计目标基因通用PCR引物和各突变点的焦磷酸测序引物,建立焦磷酸测序的突变检测方法。对接受拉米夫定、阿德福韦酯治疗的慢性乙型肝炎患者血清标本进行检测。结果:构建了乙肝病毒四种常见耐药性突变的标准株和变异株克隆,建立了分别或同时检测拉米夫定、阿德福韦酯耐药突变的焦磷酸测序方法,对68例临床耐药或疑似耐药的患者血清标本进行检测,双脱氧测序验证,检出拉米夫定耐药突变32例,阿德福韦酯耐药突变5例,其中焦磷酸测序检出20例为混合突变,而双脱氧测序显示为6例。结论:成功建立了焦磷酸测序定量检测拉米夫定、阿德福韦酯耐药基因突变的方法,构建了乙肝病毒耐药基因突变的标准质粒,为临床动态监测乙肝病毒变异病毒株、指导合理用药奠定了基础。 相似文献
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