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排序方式: 共有6797条查询结果,搜索用时 15 毫秒
1.
Patrizia Vaccino Heinz-Albert Becker Andrea Brandolini Francesco Salamini Benjamin Kilian 《Molecular genetics and genomics : MGG》2009,281(3):289-300
The celiac disease (CD) is an inflammatory condition characterized by injury to the lining of the small-intestine on exposure
to the gluten of wheat, barley and rye. The involvement of gluten in the CD syndrome has been studied in detail in bread wheat,
where a set of “toxic” and “immunogenic” peptides has been defined. For wheat diploid species, information on CD epitopes
is poor. In the present paper, we have adopted a genomic approach in order to understand the potential CD danger represented
by storage proteins in diploid wheat and sequenced a sufficiently large number of cDNA clones related to storage protein genes
of Triticum monococcum. Four bona fide toxic peptides and 13 immunogenic peptides were found. All the classes of storage proteins were shown to contain harmful
sequences. The major conclusion is that einkorn has the full potential to induce the CD syndrome, as already evident for polyploid
wheats. In addition, a complete overview of the storage protein gene arsenal in T. monococcum is provided, including a full-length HMW x-type sequence and two partial HMW y-type sequences.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Paolo d’Errico Marina Boido Antonio Piras Valeria Valsecchi Elena De Amicis Denise Locatelli Silvia Capra Francesco Vagni Alessandro Vercelli Giorgio Battaglia 《PloS one》2013,8(12)
Loss of the survival motor neuron gene (SMN1) is responsible for spinal muscular atrophy (SMA), the most common inherited cause of infant mortality. Even though the SMA phenotype is traditionally considered as related to spinal motor neuron loss, it remains debated whether the specific targeting of motor neurons could represent the best therapeutic option for the disease. We here investigated, using stereological quantification methods, the spinal cord and cerebral motor cortex of ∆7 SMA mice during development, to verify extent and selectivity of motor neuron loss. We found progressive post-natal loss of spinal motor neurons, already at pre-symptomatic stages, and a higher vulnerability of motor neurons innervating proximal and axial muscles. Larger motor neurons decreased in the course of disease, either for selective loss or specific developmental impairment. We also found a selective reduction of layer V pyramidal neurons associated with layer V gliosis in the cerebral motor cortex. Our data indicate that in the ∆7 SMA model SMN loss is critical for the spinal cord, particularly for specific motor neuron pools. Neuronal loss, however, is not selective for lower motor neurons. These data further suggest that SMA pathogenesis is likely more complex than previously anticipated. The better knowledge of SMA models might be instrumental in shaping better therapeutic options for affected patients. 相似文献
6.
G. Kozianowski F. Canganella F. A. Rainey H. Hippe G. Antranikian 《Extremophiles : life under extreme conditions》1997,1(4):171-182
A novel thermophilic spore-forming anaerobic microorganism (strain Ab9) able to grow on citrus pectin and polygalacturonic
acid (pectate) was isolated from a thermal spa in Italy. The newly isolated strain grows optimally at 70°C with a growth rate
of 0.23 h−1 with pectin and 0.12 h−1 with pectate as substrates. Xylan, starch, and glycogen are also utilized as carbon sources and thermoactive xylanolytic
(highest activity at 70°–75°C), amylolytic as well as pullulolytic enzymes (highest activity at 80°–85°C) are formed. Two
thermoactive pectate lyases were isolated from the supernatant of a 300-l culture of isolate Ab9 after growth on citrus pectin.
The two enzymes (lyases a and b) were purified to homogeneity by ammonium sulfate treatment, anion exchange chromatography, hydrophobic chromatography and
finally by preparative gel electrophoresis. After sodium dodecylsulfate (SDS) gel electrophoresis, lyase a appeared as a single polypeptide with a molecular mass of 135 000 Da whereas lyase b consisted of two subunits with molecular masses of 93 000 Da and 158 000 Da. Both enzymes displayed similar catalytic properties
with optimal activity at pH 9.0 and 80°C. The enzymes were very stable at 70°C and at 80°C with a half-life of more than 60
min. The maximal activity of the purified lyases was observed with orange pectate (100%) and pectate-sodium salt (90%), whereas
pectin was attacked to a much lesser extent (50%). The K
m values of both lyases for pectate and citrus pectin were 0.5 g·l−1 and 5.0 g·l−1, respectively. After incubation with polygalacturonic acid, mono-, di-, and tri-galacturonate were detected as final products.
A 2.5-fold increase of activity was obtained when pectate lyases were incubated in the presence of 1 mM Ca2+. The addition of 1 mM ethylenediaminetetraacetic acid (EDTA) resulted in complete inhibition of the enzymes. These heat-stable
enzymes represent the first pectate-lyases isolated and characterized from a thermophilic anaerobic bacterium. On the basis
of the results of the 16S rRNA sequence comparisons and the observed phenotypic differences, we propose strain Ab9 as a new
species of Thermoanaerobacter, namely Thermoanaerobacter italicus sp. nov.
Received: May 25, 1997 / Accepted: June 5, 1997 相似文献
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Mapping of a restriction fragment length polymorphism within the human aldolase B gene 总被引:1,自引:0,他引:1
Giovanni Paolella Rita Santamaria Pasqualina Buono Francesco Salvatore 《Human genetics》1987,77(2):115-117
Summary Peripheral blood DNA was hybridized to the full-length cDNA and the cloned structural gene of human aldolase B. With PvuII endonuclease a restriction fragment length polymorphism was detected that was present in the heterozygous state in about 21% of the individuals tested. A map of the human aldolase gene was constructed for the two groups of individuals found to produce different fragments after PvuII digestion. This allowed the localization of the polymorphic site within the gene, which was found to be due to the loss of a PvuII site in the last intron upstream from the 3 end. This polymorphism may be used as a genetic marker to study individuals affected by hereditary fructose intolerance. 相似文献
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Extensive evidence indicate that platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) play a key role in the stimulation of the 3T3 fibroblast replication: in this connection, PDGF and EGF act as a competence and a progression factor, respectively. We have previously demonstrated that EGF alone leads density-arrested EL2 rat fibroblasts to synthesize DNA and proliferate in serum-free cultures. Here, we have analyzed the role of EGF in the control of EL2 cell proliferation. Our data show a dose-related effect of EGF on DNA synthesis and cell growth, with maximal stimulation for both parameters at 20 ng/ml. On the other hand, autocrine production of PDGF or PDGF-like substances by EL2 cells is seemingly excluded by experiments with anti-PDGF serum or medium conditioned by EL2 fibroblasts. EGF binding studies show that EL2 cells possess high affinity EGF receptors, at a density level 3 to 4-fold higher than other fibroblastic lines. In addition, EL2 cells show a normal down-regulation of EGF receptors, following exposure to EGF, but PDGF, fibroblast growth factor (FGF), transforming growth factor beta (TGF beta) and bombesin have not decreased the affinity of EGF receptor for its ligand. Moreover, in EL2 cells, the EGF is able to induce the synthesis of putative intracellular regulatory proteins that govern the PDGF-induced competence in 3T3 cells. Our data indicate that EGF in EL2 cells may act as both a competence and a progression factor, via induction of the mechanisms, regulated in other cell lines by cooperation between different growth factors.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
Elvira D'Alessandro Corinna De Matteis Vaccarella Maria Luisa Lo Re Francesco Cappa Angela D'Alfonso Stefania Discepoli Maria Rosa Della Penna Giuseppe Del Porto 《Human genetics》1988,80(2):203-204
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed. 相似文献