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91.
Voisin AS Reidy B Parent B Rolland G Redondo E Gerentes D Tardieu F Muller B 《Plant, cell & environment》2006,29(9):1829-1840
The role of abscisic acid (ABA) and its possible interaction with ethylene in mediating leaf elongation response to soil water deficit are a matter of controversy. To address this question, we used a set of maize genotypes with various levels of ABA either due to natural variability or to genetic transformation targeted on NCED/VP14, a key enzyme of ABA synthesis. The transgenic lines yielded less strong phenotypes than available mutants, making it possible to use them under normal growing conditions. We focused on leaf elongation during night periods in order to avoid the confounding effect of ABA on leaf water status. Our results suggest that over a wide range, internal ABA level (measured in both leaf extracts or xylem sap) has no clear effect on leaf elongation response to soil water deficit, except in the case of an antisense line presenting the strongest reduction in ABA accumulation that showed a slight maintenance of leaf elongation during water deficit. Leaf ethylene production rate was variable and not related to water deficit except in the ABA-deficient transgenic lines where it was increased by water deficit on average but not systematically. Moreover, variability in ethylene production rate was not linked to variability in elongation rate. Our results thus suggest that neither ABA nor ethylene seems to play a major role in the control of leaf elongation response to soil water deficit. 相似文献
92.
S100 proteins form a growing subfamily of proteins related by Ca2+-binding motifs to the Efhand Ca2+-binding protein superfamily. By analyzing a human lung cancer cell line subtraction cDNA library, we have identified and characterized a new member of the human S100 family that we named S100A14 (GenBank acc. no. NM_020672). It encodes a mRNA present in several normal human tissues of epithelial origin, with the highest level of expression in colon. The full-length cDNA is 1067 nt in length, with a coding region predicting a protein of 104 amino acids that is 68% homologous to the S100A13 protein. The deduced amino acid sequence of the human S100A14 and its mouse homolog (identified as GenBank entry) contains two EF-hand Ca2+-binding domains, a myristoylation motif, a glycosylation site, and several potential protein kinase phosphorylation sites. We have mapped this gene to human chromosome 1q21, within a region where at least 15 other S100 genes are tightly clustered. A 3.2-kb genomic fragment containing the entire S100A14 was cloned and sequenced. The gene is split into four exons and three introns spanning a total of 2165 bp of genomic sequence. We examined the intracellular distribution of the epitope-tagged S100A14 protein in two human lung carcinoma cell lines and one immortalized monkey cell line. Pronounced staining was observed in the cytoplasm, suggesting an association with the plasma membrane and in the perinuclear area. We also provide evidence for heterogenic expression of S100A14 in tumors, demonstrating its overexpression in ovary, breast, and uterus tumors and underexpression in kidney, rectum, and colon tumors, a pattern suggesting distinct regulation with potentially important functions in malignant transformation. 相似文献
93.
Rüst CA Knechtle B Wirth A Knechtle P Ellenrieder B Rosemann T Lepers R 《The Chinese journal of physiology》2012,55(3):156-162
"The aim of this study was to investigate whether the characteristics of anthropometry, training or previous performance were related to an Ironman race time in recreational female Ironman triathletes. These characteristics were correlated to an Ironman race time for 53 recreational female triathletes in order to determine the predictor variables, and so be able to predict an Ironman race time for future novice triathletes. In the bi-variate analysis, no anthropometric characteristic was related to race time. The weekly cycling kilometers (r = -0.35) and hours (r = -0.32), as well as the personal best time in an Olympic distance triathlon (r = 0.49) and in a marathon (r = 0.74) were related to an Ironman race time (< 0.05). Stepwise multiple regressions showed that both the personal best time in an Olympic distance triathlon ( P = 0.0453) and in a marathon (P = 0.0030) were the best predictors for the Ironman race time (n = 28, r2 = 0.53). The race time in an Ironman triathlon might be partially predicted by the following equation (r2 = 0.53, n = 28): Race time (min) = 186.3 + 1.595 × (personal best time in an Olympic distance triathlon, min) + 1.318 × (personal best time in a marathon, min) for recreational female Ironman triathletes." 相似文献
94.
Mark Bauer Andrea Chicca Marco Tamborrini David Eisen Raissa Lerner Beat Lutz Oliver Poetz Gerd Pluschke Jürg Gertsch 《The Journal of biological chemistry》2012,287(44):36944-36967
The α-hemoglobin-derived dodecapeptide RVD-hemopressin (RVDPVNFKLLSH) has been proposed to be an endogenous agonist for the cannabinoid receptor type 1 (CB1). To study this peptide, we have raised mAbs against its C-terminal part. Using an immunoaffinity mass spectrometry approach, a whole family of N-terminally extended peptides in addition to RVD-Hpα were identified in rodent brain extracts and human and mouse plasma. We designated these peptides Pepcan-12 (RVDPVNFKLLSH) to Pepcan-23 (SALSDLHAHKLRVDPVNFKLLSH), referring to peptide length. The most abundant Pepcans found in the brain were tested for CB1 receptor binding. In the classical radioligand displacement assay, Pepcan-12 was the most efficacious ligand but only partially displaced both [3H]CP55,940 and [3H]WIN55,212-2. The data were fitted with the allosteric ternary complex model, revealing a cooperativity factor value α < 1, thus indicating a negative allosteric modulation. Dissociation kinetic studies of [3H]CP55,940 in the absence and presence of Pepcan-12 confirmed these results by showing increased dissociation rate constants induced by Pepcan-12. A fluorescently labeled Pepcan-12 analog was synthesized to investigate the binding to CB1 receptors. Competition binding studies revealed Ki values of several Pepcans in the nanomolar range. Accordingly, using competitive ELISA, we found low nanomolar concentrations of Pepcans in human plasma and ∼100 pmol/g in mouse brain. Surprisingly, Pepcan-12 exhibited potent negative allosteric modulation of the orthosteric agonist-induced cAMP accumulation, [35S]GTPγS binding, and CB1 receptor internalization. Pepcans are the first endogenous allosteric modulators identified for CB1 receptors. Given their abundance in the brain, Pepcans could play an important physiological role in modulating endocannabinoid signaling. 相似文献
95.
96.
Régis Céréghino Beat Oertli Marcello Bazzanti Cristina Coccia Arthur Compin Jeremy Biggs Nicolas Bressi Patrick Grillas Andrew Hull Thomas Kalettka Olivier Scher 《Hydrobiologia》2012,689(1):51-61
Whilst biological traits of river macroinvertebrates show unimodal responses to geographic changes in habitat conditions in Europe, we still do not know whether spatial turnover of species result in distinct combinations of biological traits for pond macroinvertebrates. Here, we used data on the occurrence of 204 macroinvertebrate taxa in 120 ponds from four biogeographic regions of Europe, to compare their biological traits. The Mediterranean, Atlantic, Alpine, and Continental regions have specific climate, vegetation and geology. Only two taxa were exclusively found in the Alpine and Continental regions, while 28 and 34 taxa were exclusively recorded in the Atlantic and Mediterranean regions, respectively. Invertebrates in the Mediterranean region allocated much energy to reproduction and resistance forms. Most Mediterranean invertebrate species had narrow thermal ranges. In Continental areas, invertebrates allocated lesser energy to reproduction and dispersal, and organisms were short lived with high diversity of feeding groups. These characteristics suggest higher resilience. The main difference between ponds in the Alpine and Atlantic regions was their elevation. Alpine conditions necessitate specific adaptations related to rapid temperature fluctuations, and low nutrient concentrations. Even if our samples did not cover the full range of pond conditions across Europe, our analyses suggest that changes in community composition have important impacts on pond ecosystem functions. Consistent information on a larger set of ponds across Europe would be much needed, but their low accessibility (unpublished data and/or not disclosed by authors) remains problematic. There is still, therefore, a pressing need for the incorporation of high quality data sets into a standardized database so that they can be further analyzed in an integrated European-wide manner. 相似文献
97.
Mayr JA Haack TB Graf E Zimmermann FA Wieland T Haberberger B Superti-Furga A Kirschner J Steinmann B Baumgartner MR Moroni I Lamantea E Zeviani M Rodenburg RJ Smeitink J Strom TM Meitinger T Sperl W Prokisch H 《American journal of human genetics》2012,90(2):314-320
Exome sequencing of an individual with congenital cataracts, hypertrophic cardiomyopathy, skeletal myopathy, and lactic acidosis, all typical symptoms of Sengers syndrome, discovered two nonsense mutations in the gene encoding mitochondrial acylglycerol kinase (AGK). Mutation screening of AGK in further individuals with congenital cataracts and cardiomyopathy identified numerous loss-of-function mutations in an additional eight families, confirming the causal nature of AGK deficiency in Sengers syndrome. The loss of AGK led to a decrease of the adenine nucleotide translocator in the inner mitochondrial membrane in muscle, consistent with a role of AGK in driving the assembly of the translocator as a result of its effects on phospholipid metabolism in mitochondria. 相似文献
98.
Nitschke Y Baujat G Botschen U Wittkampf T du Moulin M Stella J Le Merrer M Guest G Lambot K Tazarourte-Pinturier MF Chassaing N Roche O Feenstra I Loechner K Deshpande C Garber SJ Chikarmane R Steinmann B Shahinyan T Martorell L Davies J Smith WE Kahler SG McCulloch M Wraige E Loidi L Höhne W Martin L Hadj-Rabia S Terkeltaub R Rutsch F 《American journal of human genetics》2012,90(1):25-39
Spontaneous pathologic arterial calcifications in childhood can occur in generalized arterial calcification of infancy (GACI) or in pseudoxanthoma elasticum (PXE). GACI is associated with biallelic mutations in ENPP1 in the majority of cases, whereas mutations in ABCC6 are known to cause PXE. However, the genetic basis in subsets of both disease phenotypes remains elusive. We hypothesized that GACI and PXE are in a closely related spectrum of disease. We used a standardized questionnaire to retrospectively evaluate the phenotype of 92 probands with a clinical history of GACI. We obtained the ENPP1 genotype by conventional sequencing. In those patients with less than two disease-causing ENPP1 mutations, we sequenced ABCC6. We observed that three GACI patients who carried biallelic ENPP1 mutations developed typical signs of PXE between 5 and 8 years of age; these signs included angioid streaks and pseudoxanthomatous skin lesions. In 28 patients, no disease-causing ENPP1 mutation was found. In 14 of these patients, we detected pathogenic ABCC6 mutations (biallelic mutations in eight patients, monoallelic mutations in six patients). Thus, ABCC6 mutations account for a significant subset of GACI patients, and ENPP1 mutations can also be associated with PXE lesions in school-aged children. Based on the considerable overlap of genotype and phenotype of GACI and PXE, both entities appear to reflect two ends of a clinical spectrum of ectopic calcification and other organ pathologies, rather than two distinct disorders. ABCC6 and ENPP1 mutations might lead to alterations of the same physiological pathways in tissues beyond the artery. 相似文献
99.
Do HT Tselykh TV Mäkelä J Ho TH Olkkonen VM Bornhauser BC Korhonen L Zelcer N Lindholm D 《The Journal of biological chemistry》2012,287(16):12602-12611
100.
Nielsen AB Székely K Gath J Ernst M Nielsen NC Meier BH 《Journal of biomolecular NMR》2012,52(4):283-288
We present a scheme that allows the simultaneous detection of PAR and PAIN correlation spectra in a single two-dimensional
experiment. For both spectra, we obtain almost the same signal-to-noise ratio as if a PAR or PAIN spectrum is recorded separately,
which in turn implies that one of the spectra may be considered additional information for free. The experiment is based on
the observation that in a PAIN experiment, the PAR condition is always also fulfilled. The performance is demonstrated experimentally
using uniformly 13C,15N-labeled samples of N–f–MLF–OH and ubiquitin. 相似文献