Search results for "binding"
showing 10 items of 3896 documents
Carbohydrate-Mediated Biomolecular Recognition and Gating of Synthetic Ion Channels
2013
Nanochannel-based biosensing devices have been proposed for selective detection of protein analyte molecules. However, the design and miniaturization of reusable channel-based biosensors is still a challenge in nanoscience and biotechnology. We present here a reusable nanofluidic biosensor based on reversible lectin-carbohydrate interactions. The nanochannels are fabricated in heavy ion tracked polymer membranes. The channel walls are functionalized with p-aminophenyl alpha-D-mannopyranoside (APMP) monolayers through carbodiimide coupling chemistry. The chemical (mannopyranoside) groups on the inner channel walls serve as binding sites and interact with specific protein molecules. The bindi…
Characterization of aging-associated up-regulation of constitutive nuclear factor-kappa B binding activity.
2001
Changes occur in gene expression during aging in vivo and in replicative senescence in vitro, suggesting that aging can affect gene regulation. We have recently observed age-related changes in ubiquitously expressed, oxidative stress-responsive nuclear factor-kappa B (NF-kappa B) pathway during aging. Here we report a significant age-related increase in nuclear NF-kappa B binding activity together with increased protein levels of p52 and p65 components in rat liver. An additional, higher molecular weight protein band seen in their western blots suggests that their post-translational modification (but not phosphorylation) occurs in liver, which might affect their nuclear localization and bin…
Activity of mannose-binding lectin in centenarians
2012
Summary We analyzed MBL2 gene variants in two cohorts of centenarians, octo-nonagenarians and nonagenarians, and in the general population, one from Sardinia Island (Italy), recruited in the frame of the AKea study, and another from Campania (southern Italy), to search for haplotypes related to longevity. We also assessed in vitro the effect of mannose-binding lectin (MBL) on various human cells at different stage of senescence. The frequency of high and null activity haplotypes was significantly lower, and the frequency of intermediate activity haplotype significantly higher in centenarians and in subjects between 80 and 99 years from both the cohorts as compared each to the general popula…
Down-Regulation of Ku Autoantigen, DNA-Dependent Protein Kinase, and Poly(ADP-ribose) Polymerase during Cellular Senescence
1997
During aging and cellular senescence mutations accumulate in genomic and mitochondrial DNA. Ku autoantigens, DNA-dependent protein kinase, and poly (ADP-ribose) polymerase have an essential role in DNA damage recognition. Our purpose was to find out whether cellular senescence of fibroblasts affects the protein components that recognize DNA damage and induce the repair process. We compared presenescent and replicatively senescent human WI-38 fibroblasts with each other and with SV-40 immortalized and serum-deficient quiescent WI-38 cells. Our results showed that replicative senescence significantly decreased the nuclear level of both p70 and p86 components of Ku autoantigen. SV-40 immortali…
Age-related changes in the regulation of transcription factor NF-kappa B in rat brain.
1997
Aging process involves an increase in stress at cellular level. We studied whether aging affects the regulation of stress responsive transcription factor NF-kappa B in brain samples of Wistar rats. Hippocampus, cerebellum, and temporal and frontal lobes of cortex were studied. We observed a significant up-regulation in the constitutive, nucleus-located NF-kappa B binding activity in 30-month-old Wistar rats compared to young and 18-month-old rats. The increase was most prominent in cerebellum and in frontal cortex, but age-related changes did not occur in hippocampus. Inducible, cytoplasmic NF-kappa B binding activity was not affected by aging in any of the samples studied. Western blot ass…
Neurobiological foundations of multisensory processing integration in people with autism spectrum disorders: The role of the medial prefrontal cortex
2014
This review aims to relate the sensory processing problems in people with Autism spectrum disorders (ASD), especially Multisensory interaction (MSI), to the role of the medial prefrontal cortex (mPFC) by exploring neuroanatomical findings; brain connectivity and Default Network (DN); global or locally directed attention; and temporal multisensory binding. The mPFC is part of the brain’s DN, which is deactivated when attention is focused on a particular task and activated on rest when spontaneous cognition emerges. In those with ASD, it is hypoactive and the higher the social impairment the greater the atypical activity. With an immature DN, cross-modal integration is impaired, resulting in …
One precursor, three apolipoproteins: The relationship between two crustacean lipoproteins, the large discoidal lipoprotein and the high density lipo…
2014
The novel discoidal lipoprotein (dLp) recently detected in the crayfish, differs from other crustacean lipoproteins in its large size, apoprotein composition and high lipid binding capacity, We identified the dLp sequence by transcriptome analyses of the hepatopancreas and mass spectrometry. Further de novo assembly of the NGS data followed by BLAST searches using the sequence of the high density lipoprotein/1-glucan binding protein (HDL-BGBP) of Astacus leptodactylus as query revealed a putative precursor molecule with an open reading frame of 14.7 kb and a deduced primary structure of 4889 amino acids. The presence of an N-terminal lipid bind- ing domain and a DUF 1943 domain suggests the…
Host glycoprotein Gp96 and scavenger receptor SREC interact with PorB of disseminating Neisseria gonorrhoeae in an epithelial invasion pathway.
2007
Neisseria gonorrhoeae expresses numerous surface proteins that mediate bacterial adherence and invasion during infection. Gonococci expressing serotype A of the major outer membrane porin PorB (PorB(IA)) are frequently isolated from patients with severe disseminating infections. PorB(IA) triggers efficient adherence and invasion under low phosphate conditions mimicking systemic bloodstream infections. Here, we identify the human heat shock glycoprotein Gp96 and the scavenger receptor SREC as PorB(IA)-specific receptors. Gonococci expressing PorB(IA), but not those expressing PorB serotype B instead, bind to purified native or recombinant Gp96. Depletion of Gp96 from host cells prevented adh…
Nucleotide variation in the VP7 gene affects PCR genotyping of G9 rotaviruses identified in Italy
2003
A modified (aFT9m) and a degenerate (aFT9d) version of the rotavirus G9-specific primer (aFT9) allowed strains that were previously untypable, because of point mutations accumulating at the primer binding site, to be G typed by reverse transcription-polymerase chain reaction. The strains were collected during 2001-2002 in Italy in hospitals of the Apulia region, from children affected by severe rotavirus-associated enteritis. Using a wide selection of G9 rotaviruses detected worldwide, sequencing of the G9 untypable strains, sequence comparison, and phylogenetic analysis showed that the Italian strains have strong genetic similarity (< or =99.4%) to G9 rotaviruses identified recently in man…
Cholesterol Starvation and Hypoxia Activate the FVII Gene via the SREBP1-GILZ Pathway in Ovarian Cancer Cells to Produce Procoagulant Microvesicles
2019
AbstractInteraction between the transcription factors, hypoxia-inducible factor (HIF1α and HIF2α) and Sp1, mediates hypoxia-driven expression of FVII gene encoding coagulation factor VII (fVII) in ovarian clear cell carcinoma (CCC) cells. This mechanism is synergistically enhanced in response to serum starvation, a condition possibly associated with tumor hypoxia. This transcriptional response potentially results in venous thromboembolism, a common complication in cancer patients by producing procoagulant extracellular vesicles (EVs). However, which deficient serum factors are responsible for this characteristic transcriptional mechanism is unknown. Here, we report that cholesterol deficien…