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31.
Liana Tsiatsiani Evy Timmerman Pieter-Jan De Bock Dominique Vercammen Simon Stael Brigitte van de Cotte An Staes Marc Goethals Tine Beunens Petra Van Damme Kris Gevaert Frank Van Breusegem 《The Plant cell》2013,25(8):2831-2847
Metacaspases are distant relatives of the metazoan caspases, found in plants, fungi, and protists. However, in contrast with caspases, information about the physiological substrates of metacaspases is still scarce. By means of N-terminal combined fractional diagonal chromatography, the physiological substrates of METACASPASE9 (MC9; AT5G04200) were identified in young seedlings of Arabidopsis thaliana on the proteome-wide level, providing additional insight into MC9 cleavage specificity and revealing a previously unknown preference for acidic residues at the substrate prime site position P1′. The functionalities of the identified MC9 substrates hinted at metacaspase functions other than those related to cell death. These results allowed us to resolve the substrate specificity of MC9 in more detail and indicated that the activity of phosphoenolpyruvate carboxykinase 1 (AT4G37870), a key enzyme in gluconeogenesis, is enhanced upon MC9-dependent proteolysis. 相似文献
32.
33.
Alexander Christmann Jacqueline Christmann Petra Schiller Burkhard Frenzel 《Trees - Structure and Function》1996,10(5):331-338
Levels of indole-3-acetic acid (IAA) were determined in needles from silver fir (Abies alba Mill.) trees in the northern Black Forest. IAA was quantified by gas chromatography (GC) as 1-heptafluorobutyryl-IAA-methylester
(HFB-IAA-ME) using electron capture detection. Prior to GC analysis, extensive purification of needle extracts was performed
employing two HPLC steps. Peak identity of HFB-IAA-ME was confirmed by combined gas chromatography-mass spectrometry in selected
samples. Levels of IAA in needles belonging to different needle age-classes exhibited a cyclic seasonal pattern with highest
concentrations in winter and lowest levels in spring when bud-break occurred. Such a cyclic seasonal pattern of IAA levels
was also observed in needles from declining fir trees or fir trees suffering from a strong sulfur impact (S-impact) in the
field due to a local SO2 source. Levels of IAA increased with increasing needle age. This age dependency of IAA concentrations was most pronounced
in late autumn when IAA levels were high and nearly disappeared in spring when IAA levels reached their minimum. In needles
from declining fir trees or fir trees suffering from a strong S-impact in the field, IAA levels hardly increased with increasing
needle age. It is suggested that in healthy trees high levels of IAA protect older needles from abscission and that the considerable
losses of older needles of declining fir trees or of fir trees under S-impact are a consequence of the low levels of IAA found
in older needles of such trees.
Received: 4 May 1995 / Accepted: 29 August 1995 相似文献
34.
Schumacher J Otte AC Becker T Sun Y Wienker TF Wirth B Franke P Abou Jamra R Propping P Deckert J Nöthen MM Cichon S 《Human genetics》2003,114(1):115-117
A duplication of chromosome 15q24-q26 (DUP25) has been reported to be associated with anxiety disorders. We tested for the presence of DUP25 in a sample of 50 patients with panic disorder and 50 controls using a quantitative real-time PCR approach. Contrary to the original finding, our results were compatible with the absence of DUP25, and no significant difference could be detected between patients and controls (P=1.0). Thus, our study does not support the hypothesis of an involvement of DUP25 in panic disorder. 相似文献
35.
Eight compounds exuded from young roots of black locust (Robinia pseudoacacia) were separated by two-dimensional HPTLC, by HPLC and GC, and were identified by spectroscopic methods (ultraviolet/visible
spectroscopy and mass spectrometry) as 4′,7-dihydroxyflavone, apigenin, naringenin, chrysoeriol and isoliquiritigenin. Structural
assignments were confirmed by comparison with authentic standards. The capacity to induce β-galactosidase activity in Rhizobium sp. NGR234 containing a nod box::lacZ fusion on plasmid pA27 identified these flavonoids and the chalcone as nod gene inducers. This indicates the important role of these compounds in nodulation of this legume tree.
Received: 26 July 1996 / Accepted: 9 September 1996 相似文献
36.
CaGE: cardiac gene expression knowledgebase 总被引:4,自引:0,他引:4
Bober M Wiehe K Yung C Onal Suzek T Lin M Baumgartner W Winslow R 《Bioinformatics (Oxford, England)》2002,18(7):1013-1014
CaGE is a Cardiac Gene Expression knowledgebase we have developed to facilitate the analysis of genes important to human cardiac function. CaGE integrates the functionality of the LocusLink database with data from several human cardiac expression libraries, phenotypic data from OMIM and data from large-scale microarray gene expression studies to create a knowledgebase of gene expression in human cardiac tissue. The knowledgebase is fully searchable via the web using several intuitive query interfaces. Results can be displayed in several concise easy to navigate formats. AVAILABILITY: CaGE is located at http://www.cage.wbmei.jhu.edu 相似文献
37.
Beblo K Douki T Schmalz G Rachel R Wirth R Huber H Reitz G Rettberg P 《Archives of microbiology》2011,193(11):797-809
In this study, we investigated the ability of several (hyper-) thermophilic Archaea and phylogenetically deep-branching thermophilic
Bacteria to survive high fluences of monochromatic UV-C (254 nm) and high doses of ionizing radiation, respectively. Nine
out of fourteen tested microorganisms showed a surprisingly high tolerance against ionizing radiation, and two species (Aquifex pyrophilus and Ignicoccus hospitalis) were even able to survive 20 kGy. Therefore, these species had a comparable survivability after exposure to ionizing radiation
such as Deinococcus radiodurans. In contrast, there was nearly no difference in survival of the tested strains after exposure to UV-C under anoxic conditions.
If the cells had been dried in advance of UV-C irradiation, they were more sensitive to UV-C radiation compared with cells
irradiated in liquid suspension; this effect could be reversed by the addition of protective material like sulfidic ores before
irradiation. By exposure to UV-C, photoproducts were formed in the DNA of irradiated Archaea and Bacteria. The distribution
of the main photoproducts was species specific, but the amount of the photoproducts was only partly dependent on the applied
fluence. Overall, our results show that tolerance to radiation seems to be a common phenomenon among thermophilic and hyperthermophilic
microorganisms. 相似文献
38.
Margalith I Suter C Ballmer B Schwarz P Tiberi C Sonati T Falsig J Nyström S Hammarström P Aslund A Nilsson KP Yam A Whitters E Hornemann S Aguzzi A 《The Journal of biological chemistry》2012,287(23):18872-18887
Luminescent conjugated polymers (LCPs) interact with ordered protein aggregates and sensitively detect amyloids of many different proteins, suggesting that they may possess antiprion properties. Here, we show that a variety of anionic, cationic, and zwitterionic LCPs reduced the infectivity of prion-containing brain homogenates and of prion-infected cerebellar organotypic cultured slices and decreased the amount of scrapie isoform of PrP(C) (PrP(Sc)) oligomers that could be captured in an avidity assay. Paradoxically, treatment enhanced the resistance of PrP(Sc) to proteolysis, triggered the compaction, and enhanced the resistance to proteolysis of recombinant mouse PrP(23-231) fibers. These results suggest that LCPs act as antiprion agents by transitioning PrP aggregates into structures with reduced frangibility. Moreover, ELISA on cerebellar organotypic cultured slices and in vitro conversion assays with mouse PrP(23-231) indicated that poly(thiophene-3-acetic acid) may additionally interfere with the generation of PrP(Sc) by stabilizing the conformation of PrP(C) or of a transition intermediate. Therefore, LCPs represent a novel class of antiprion agents whose mode of action appears to rely on hyperstabilization, rather than destabilization, of PrP(Sc) deposits. 相似文献
39.
40.
Veenma D Beurskens N Douben H Eussen B Noomen P Govaerts L Grijseels E Lequin M de Krijger R Tibboel D de Klein A Van Opstal D 《PloS one》2010,5(12):e15348
In this paper we present the detailed clinical and cytogenetic analysis of a prenatally detected complex Congenital Diaphragmatic Hernia (CDH) patient with a mosaic unbalanced translocation (5;12). High-resolution whole genome SNP array confirmed a low-level mosaicism (20%) in uncultured cells, underlining the value of array technology for identification studies. Subsequently, targeted Fluorescence In-Situ Hybridization in postmortem collected tissues demonstrated a similar low-level mosaicism, independently of the affected status of the tissue. Thus, a higher incidence of the genetic aberration in affected organs as lung and diaphragm cannot explain the severe phenotype of this complex CDH patient. Comparison with other described chromosome 5p and 12p anomalies indicated that half of the features presented in our patient (including the diaphragm defect) could be attributed to both chromosomal areas. In contrast, a few features such as the palpebral downslant, the broad nasal bridge, the micrognathia, microcephaly, abnormal dermatoglyphics and IUGR better fitted the 5p associated syndromes only. This study underlines the fact that low-level mosaicism can be associated with severe birth defects including CDH. The contribution of mosaicism to human diseases and specifically to congenital anomalies and spontaneous abortions becomes more and more accepted, although its phenotypic consequences are poorly described phenomena leading to counseling issues. Therefore, thorough follow-up of mosaic aberrations such as presented here is indicated in order to provide genetic counselors a more evidence based prediction of fetal prognosis in the future. 相似文献