158 research outputs found
Tomato plants transgenic for an Arabidopsis thaliana cystein proteinase inhibitor (Atcys) impair the life cycle of Helicoverpa armigera (Hüb.)
Atcys tomato (Lycopersicon esculentum Mill.) transgenic plants, expressing a cystein proteinase inhibition level double than the untransformed control (Speranza et al. in press), were used for in vivo assays with H. armigera larvae. This insect pest, extremely polyphagous, has recently caused severe damages to the outdoor tomato crop due to the dropping of infested young fruits and to fruit rotting because of the larval galleries.
Plants of the cv. Riogrande (RIG) and of the corresponding Atcys homozygous transgenic line (BG-106) were grown in greenhouse and leaves utilized for feeding H. armigera larvae, reared for four days with artificial diet. The recorded data were larval weight (every two days until the cocoon stage), cocoon sex and morphometric traits, number of adults emerged from the cocoon, number of layed and hatched eggs. The mean weight was generally higher when larvae were fed with BG-106 leaves. By subdividing in three periods the larval life, no difference in mortality was observed between larvae reared with control (RIG) and with BG-106 leaves. The percentage of adults emerged from the cocoon was 81% and 76% for the control and BG-106 respectively. The sex ratio (males/females) was in favour of the female sex both for the RIG (0.87) and BG-106 (0.73) cocoons. On average, the fertility (number of layed eggs) of the BG-106 fed females was 33% lower than the control. By considering the percentage of hatched eggs (emerged larvae), the value obtained was 6.8% for BG-106 against 11% for RIG.
According to these data, in Atcys transgenic tomato (BG-106), a level of cystein proteinase inhibition double than the untransformed control, is sufficient to negatively influence the H. armigera biological cycle, even if the weight of the larvae fed with the BG-106 leaves is on average higher than the control (RIG). The last datum is in agreement with similar experiments reported in literature where the effect of proteinase inhibitors is tested in different host-pest systems
Identification of proteinaceous binders in paintings: A targeted proteomic approach for cultural heritage
Abstract Identification of proteins in paintings and polychrome objects is a challenge, which requires the development of tailored analytical approaches. In the present study, a targeted proteomics approach was developed for discriminating among the three most common proteinaceous materials used as paint binders, i.e. milk, egg, and animal glue. In this study a specific database of peptides was created based on tandem MS analyses of tryptic digests of several paint samples collected from a variety of art objects of different ages and conservation conditions. Specific peptide markers of each protein were then selected and monitored by LC-MSMS in Multiple Reaction Monitoring (MRM) ion mode, together with their specific precursor ion-product ion transitions, as defined by their unique amino acid sequence. The developed method enabled a sensitive and reliable detection of the target peptides in a selection of case studies, leading to the unambiguous identification of the proteins used as paint binders. The method showed greatly increased sensitivity compared to currently available strategies
12 Sex-related differential susceptibility to ponatinib-induced cardiotoxicity and its relationship to modulation of notch signalling in a muine model
Abstract
Aims
Ponatinib (PON), a tyrosine kinase inhibitor approved in chronic myeloid leukaemia, has proven cardiovascular toxicity. Although sex is a risk factor for PON-induced cardiotoxicity in humans, little is known about its mechanisms, in general, and sex-related mechanisms in particular. To determine the mechanisms of sex-related PON-induced cardiotoxicity and identify potential rescue strategies in a murine model.
Methods
Twenty-four-month-old male and female C57B5 mice were treated with 3 mg/kg/day of PON or vehicle via oral gavage for 28 days, with/without siRNA-Notch1 or siRNA-scrambled via tail vein every 3 days.
Results
PON + scrambled siRNA-treated male mice had a higher number of TUNEL-positive cells, a higher percentage of senescence-associated β-galactosidase positive senescent cardiac areas, as well as a lower reactivity degree for the survival marker Bmi1 than female counterparts. Proteomics analysis of cardiac tissue showed upstream activation of nitric oxide synthase (NOS) type 2, downstream activation of cell death and production of reactive oxygen species in PON + scrambled siRNA- compared to vehicle or PON + Notch1 siRNA-treated male mice. Upstream analysis showed beta-estradiol activation, while downstream analysis showed activation of cell survival and inhibition of cell death in PON + scrambled siRNA compared to vehicle-treated female mice. PON + scrambled siRNA-treated mice also showed a down-regulation of cardiac actin, which was more marked in male; as well as vessel density, which was more marked in female mice. Female hearts showed a greater extent of cardiac fibrosis than male counterparts at baseline, with no significant changes after PON treatment. In contrast, PON + scrambled siRNA-treated mice had less fibrosis than vehicle or PON + Notch1-siRNA-treated mice. Left ventricular systolic dysfunction shown in PON + scrambled siRNA-treated male mice and—to a lesser extent—by female mice was similarly reversed in both PON + Notch1-siRNA-treated male and female mice (Table 1).
Conclusions
We found a sex-related differential susceptibility and Notch1 modulation in PON-induced cardiotoxicity. This can improve our understanding of sex-related differences and help identify biomarkers in PON cardiotoxicity
Genome-wide mapping of 8-oxo-7,8-dihydro-2'-deoxyguanosine reveals accumulation of oxidatively-generated damage at DNA replication origins within transcribed long genes of mammalian cells
8-Oxo-7,8-dihydro-2-deoxyguanosine (8-oxodG) is
one of the major DNA modifications and a potent
pre-mutagenic lesion prone to mispair with 2-
deoxyadenosine (dA). Several thousand residues of
8-oxodG are constitutively generated in the genome
of mammalian cells, but their genomic distribution
has not yet been fully characterized. Here, by
using OxiDIP-Seq, a highly sensitive methodology
that uses immuno-precipitation with efficient anti–
8-oxodG antibodies combined with high-throughput
sequencing, we report the genome-wide distribution
of 8-oxodG in human non-tumorigenic epithelial
breast cells (MCF10A), and mouse embryonic
fibroblasts (MEFs). OxiDIP-Seq revealed sites of 8-
oxodG accumulation overlapping with H2AX ChIPSeq
signals within the gene body of transcribed long
genes, particularly at the DNA replication origins
contained therein. We propose that the presence of
persistent single-stranded DNA, as a consequence
of transcription-replication clashes at these sites, determines
local vulnerability to DNA oxidation and/or
its slow repair. This oxidatively-generated damage,
likely in combination with other kinds of lesion, might
contribute to the formation of DNA double strand
breaks and activation of DNA damage response
The TRILL project: increasing the technological readiness of Laue lenses
Hard X-/soft Gamma-ray astronomy (> 100 keV) is a crucial field for the study
of important astrophysical phenomena such as the 511 keV positron annihilation
line in the Galactic center region and its origin, gamma-ray bursts, soft
gamma-ray repeaters, nuclear lines from SN explosions and more. However,
several key questions in this field require sensitivity and angular resolution
that are hardly achievable with present technology. A new generation of
instruments suitable to focus hard X-/soft Gamma-rays is necessary to overcome
the technological limitations of current direct-viewing telescopes. One
solution is using Laue lenses based on Bragg's diffraction in a transmission
configuration. To date, this technology is in an advanced stage of development
and further efforts are being made in order to significantly increase its
technology readiness level (TRL). To this end, massive production of suitable
crystals is required, as well as an improvement of the capability of their
alignment. Such a technological improvement could be exploited in stratospheric
balloon experiments and, ultimately, in space missions with a telescope of
about 20 m focal length, capable of focusing over a broad energy pass-band. We
present the latest technological developments of the TRILL (Technological
Readiness Increase for Laue Lenses) project, supported by ASI, devoted to the
advancement of the technological readiness of Laue lenses. We show the method
we developed for preparing suitable bent Germanium and Silicon crystals and the
latest advancements in crystals alignment technology.Comment: arXiv admin note: text overlap with arXiv:2211.1688
Wilson Disease Protein ATP7B Utilizes Lysosomal Exocytosis to Maintain Copper Homeostasis
SummaryCopper is an essential yet toxic metal and its overload causes Wilson disease, a disorder due to mutations in copper transporter ATP7B. To remove excess copper into the bile, ATP7B traffics toward canalicular area of hepatocytes. However, the trafficking mechanisms of ATP7B remain elusive. Here, we show that, in response to elevated copper, ATP7B moves from the Golgi to lysosomes and imports metal into their lumen. ATP7B enables lysosomes to undergo exocytosis through the interaction with p62 subunit of dynactin that allows lysosome translocation toward the canalicular pole of hepatocytes. Activation of lysosomal exocytosis stimulates copper clearance from the hepatocytes and rescues the most frequent Wilson-disease-causing ATP7B mutant to the appropriate functional site. Our findings indicate that lysosomes serve as an important intermediate in ATP7B trafficking, whereas lysosomal exocytosis operates as an integral process in copper excretion and hence can be targeted for therapeutic approaches to combat Wilson disease
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