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1.
Isolation and characterization of plasma membrane-associated cortical granules from sea urchin eggs 总被引:9,自引:6,他引:3
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Cortical granules, which are specialized secretory organelles found in ova of many organisms, have been isolated from the eggs of the sea urchins Arbacia punctulata and Strongylocentrtus pupuratus by a simple, rapid procedure. Electron micropscope examination of cortical granules prepared by this procedure reveals that they are tightly attached to large segments of the plasma membrane and its associated vitelline layer. Further evidence that he cortical granules were associated with these cell surface layers was obtained by (125)I-labeling techniques. The cortical granule preparations were found to be rich in proteoesterase, which was purified 32-fold over that detected in a crude homogenate. Similarly, the specific radioactivity of a (125)I-labeled, surface glycoprotein was increased 40-fold. These facts, coupled with electron microscope observations, indicate the isolation procedure yields a preparation in which both the cortical granules and the plasma membrane-vitelline layer are purified to the same extent. Gel electrophoresis of the membrane-associated cortical granule preparation reveals the presence of at least eight polypeptides. The major polypeptide, which is a glycotprotein of apparent mol wt of 100,000, contains most of the radioactivity introduced by (125)I-labeling of the intact eggs. Lysis of the cortical granules is observed under hypotonic conditions, or under isotonic conditions if Ca(2+) ion is present. When lysis is under isotonic conditions is induced by addition of Ca(2+) ion, the electron-dense contents of the granules remain insoluble. In contrast, hypotonic lysis results in release of the contents of the granule in a soluble form. However, in both cases the (125)I-labeled glycoprotein remains insoluble, presumably because it is a component of either the plasma membrane or the vitelline layer. All these findings indicate that, using this purified preparation, it should be possible to carry out in vitro studies to better define some of the initial, surface-related events observed in vivo upon fertilization. 相似文献
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3.
Lisi V Guala A Lopez A Vitali M Spadoni E Olivieri C Danesino C Mottes M 《Genetic counseling (Geneva, Switzerland)》2002,13(2):163-170
The Stickler syndrome is among the most common heritable disorders of connective tissue. The syndrome fully expressed clinical phenotype includes the degeneration of the vitreous gel and retina, frequently associated with myopia, accompanied by non-ocular features, such as craniofacial dysmorphisms or malformations, hearing impairment, skeletal dysplasia and progressive arthropathy. So far, mutations at three collagen loci, COL2A1, COL11A1 and COL11A2, have been found in Stickler syndrome patients, with about two thirds of investigated familial cases found to be associated to COL2A1 gene mutations. We report on a three generation family in which a diagnosis of Stickler syndrome was made and linkage analysis suggested COL2A1 to be the causing gene. These data permitted us to perform two prenatal diagnosis analysing the 3'VNTR polymorphism of the involved gene on amniocytes' DNA and to provide the family with genetic counselling and paediatric support at the delivery. 相似文献
4.
Phylogenetic utility of the nuclear gene arginine decarboxylase: an example from Brassicaceae 总被引:10,自引:2,他引:8
Arginine decarboxylase (ADC) is an important enzyme in the production of
putrescine and polyamines in plants. It is encoded by a single or low-copy
nuclear gene that lacks introns in sequences studied to date. The rate of
Adc amino acid sequence evolution is similar to that of ndhF for the
angiosperm family studied. Highly conserved regions provide several target
sites for PCR priming and sequencing and aid in nucleotide and amino acid
sequence alignment across a range of taxonomic levels, while a variable
region provides an increased number of potentially informative characters
relative to ndhF for the taxa surveyed. The utility of the Adc gene in
plant molecular systematic studies is demonstrated by analysis of its
partial nucleotide sequences obtained from 13 representatives of
Brassicaceae and 3 outgroup taxa, 2 from the mustard oil clade (order
Capparales) and 1 from the related order Malvales. Two copies of the Adc
gene, Adc1 and Adc2, are found in all members of the Brassicaceae studied
to data except the basal genus Aethionema. The resulting Adc gene tree
provides robust phylogenetic data regarding relationships within the
complex mustard family, as well as independent support for proposed tribal
realignments based on other molecular data sets such as those from
chloroplast DNA.
相似文献
5.
Jean-Louis Spadoni Pierre Rucart Sigrid Le Clerc Dani?lle van Manen Cédric Coulonges Damien Ulveling Vincent Laville Taoufik Labib Lieng Taing Olivier Delaneau Matthieu Montes Hanneke Schuitemaker Josselin Noirel Jean-Fran?ois Zagury 《PloS one》2015,10(9)
Background
Many genome-wide association studies have been performed on progression towards the acquired immune deficiency syndrome (AIDS) and they mainly identified associations within the HLA loci. In this study, we demonstrate that the integration of biological information, namely gene expression data, can enhance the sensitivity of genetic studies to unravel new genetic associations relevant to AIDS.Methods
We collated the biological information compiled from three databases of expression quantitative trait loci (eQTLs) involved in cells of the immune system. We derived a list of single nucleotide polymorphisms (SNPs) that are functional in that they correlate with differential expression of genes in at least two of the databases. We tested the association of those SNPs with AIDS progression in two cohorts, GRIV and ACS. Tests on permuted phenotypes of the GRIV and ACS cohorts or on randomised sets of equivalent SNPs allowed us to assess the statistical robustness of this method and to estimate the true positive rate.Results
Eight genes were identified with high confidence (p = 0.001, rate of true positives 75%). Some of those genes had previously been linked with HIV infection. Notably, ENTPD4 belongs to the same family as CD39, whose expression has already been associated with AIDS progression; while DNAJB12 is part of the HSP90 pathway, which is involved in the control of HIV latency. Our study also drew our attention to lesser-known functions such as mitochondrial ribosomal proteins and a zinc finger protein, ZFP57, which could be central to the effectiveness of HIV infection. Interestingly, for six out of those eight genes, down-regulation is associated with non-progression, which makes them appealing targets to develop drugs against HIV. 相似文献6.
Spadoni G Bedini A Orlando P Lucarini S Tarzia G Mor M Rivara S Lucini V Pannacci M Scaglione F 《Bioorganic & medicinal chemistry》2011,19(16):4910-4916
We report the synthesis, binding properties and intrinsic activity at MT(1) and MT(2) melatonin receptors of new dimeric melatonin receptor ligands in which two units of the monomeric agonist N-{2-[(3-methoxyphenyl)methylamino]ethyl}acetamide (1) are linked together through different anchor points. Dimerization of compound 1 through the methoxy substituent leads to a substantial improvement in selectivity for the MT(1) receptor, and to a partial agonist behavior. Compound 3a, with a trimethylene linker, was the most selective for the MT(1) subtype (112-fold selectivity) and compound 3d, characterized by a hexamethylene spacer, had the highest MT(1) binding affinity (pK(iMT1)=8.47) and 54-fold MT(1)-selectivity. Dimerization through the aniline nitrogen of 1 abolished MT(1) selectivity, leading to compounds with either a full agonist or an antagonist behavior depending on the nature of the linker. 相似文献
7.
Annerieke C van Groenestijn Ingrid GL van de Port Carin D Schröder Marcel WM Post Hepke F Grupstra Esther T Kruitwagen Harmen van der Linde Reinout O van Vliet Margreet GH van de Weerd Leonard H van den Berg Eline Lindeman 《BMC neurology》2011,11(1):1-11
Background
Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.Methods
We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.Results
Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.Conclusions
The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain. 相似文献8.
9.
Background
As an individual moves from adolescence to adulthood, they need to form a new sense of self as their environment changes from a limited to a more expansive structure. During this critical stage in development the last dramatic steps of neural development occur and numerous psychiatric conditions begin to manifest. Currently, there is no measure that aids in the quantification of how the individual is adapting to, and conceptualizing their role in, these new structures. To fill this gap we created the Self and World Evaluation Expressions Test(SWEET).Method
Sixty-five young adults (20.6 years-old), 36 with a history of drug use, completed the SWEET. A factor analysis was performed on the SWEET and the resultant factors were correlated with psychological, neuropsychological, and neuroanatomical battery that included both T1-wieghted and diffusion tensor magnetic resonance imaging scans.Results
We derived four factors: Self, Social-Emotional, Financial-Intellectual, and Spirituality. While showing limited relationships to psychological and neuropsychological measures, both white matter integrity and gray matter density showed significant relationships with SWEET factors.Conclusions
These findings suggest that while individual responses may not be indicative of psychological or cognitive processes they may relate to changes in brain structure. Several of these structures, such as the negative correlation of the affective impact of world with the dorsal anterior corpus callosum white matter integrity have been observed in psychiatric conditions (e.g., obsessive-compulsive disorder). Further longitudinal research using the SWEET may help understand the impact of dramatic shifts in self/world conceptualization and potentially link these shifts to underlying changes in brain structure. 相似文献10.
Elisa Beghetto Andrea Pucci Olga Minenkova Andrea Spadoni Luca Bruno Wilma Buffolano Dominique Soldati Franco Felici Nicola Gargano 《International journal for parasitology》2001,31(14)
Excreted secreted antigens of the protozoan parasite Toxoplasma gondii play a key role in stimulating the host immune system during acute and chronic infection. With the aim of identifying the immunodominant epitopes of T. gondii antigens involved in the human B-cell response against the parasite, we employed a novel immunological approach. A library of cDNA fragments from T. gondii tachyzoites was displayed as fusion proteins to the amino-terminus of lambda bacteriophage capsid protein D. The lambdaD-tachyzoite library was then affinity-selected by using a panel of sera of pregnant women, all infected with the parasite. Some of the clones identified through this procedure matched the sequence of the dense granule GRA1 protein (p24), allowing us to identify its antigenic regions. In particular, the analysis of human antibody response against the recombinant GRA1 antigen fragments revealed the existence of an immunodominant epitope (epi-24 peptide). 相似文献