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991.
Linkage analysis identifies a novel locus for restless legs syndrome on chromosome 2q in a South Tyrolean population isolate 下载免费PDF全文
Pichler I Marroni F Volpato CB Gusella JF Klein C Casari G De Grandi A Pramstaller PP 《American journal of human genetics》2006,79(4):716-723
Restless legs syndrome (RLS) is a common neurological condition with three loci (12q, 14q, and 9p) described so far, although none of these genes has yet been identified. We report a genomewide linkage scan of patients with RLS (n=37) assessed in a population isolate (n=530) of South Tyrol (Italy). Using both nonparametric and parametric analyses, we initially obtained suggestive evidence of a novel locus on chromosome 2q, with nominal evidence of linkage on chromosomes 5p and 17p. Follow-up genotyping yielded significant evidence of linkage (nonparametric LOD score 5.5, P相似文献
992.
993.
Kirfel J Senderek J Moser M Röper A Stendel C Bergmann C Zerres K Buettner R 《Gene expression patterns : GEP》2006,6(8):978-984
Autosomal recessive hereditary motor and sensory neuropathy (HMSN) or Charcot-Marie-Tooth disease (CMT) is a clinically and genetically heterogeneous disorder of the peripheral nervous system. The clinical picture includes progressive distal weakness and atrophy, foot deformities, and distal sensory loss. For autosomal recessive CMT type 4B2 one locus was mapped to chromosome 11p15. Recently, mutations in SET binding factor 2 (SBF2), were identified as cause of CMT4B2. SBF2 is a member of the pseudo-phosphatase branch of myotubularins and all disease-associated mutations known to date lead to shortened or truncated proteins, also implicating loss-of-function. Here, we describe the molecular cloning and the expression pattern of Sbf2. The mRNA spans around 8 kb, and the protein shares high amino acid identity compared to the human protein suggesting a conserved function. Sbf2 is encoded by 40 exons on murine chromosome 7. In situ hybridization, Northern blots and RT-analysis revealed a very broad pattern of Sbf2 expression. Overexpressed epitope tagged Sbf2 showed cytoplasmic distribution. Taken together, this study provides information about the mRNA expression and subcellular localization of Sbf2 and as such helps in further understanding its function in development and disease. 相似文献
994.
Ruiz-Herrera J Xoconostle-Cázares B Reynaga-Peña CG León-Ramírez C Cárabez-Trejo A 《FEMS yeast research》2006,6(7):999-1009
Conserved polypeptides of the chitin synthase genes UmCHS3 and UmCHS6 from the phytopathogenic fungus Ustilago maydis were utilized as immunogens to obtain polyclonal antibodies that were purified by affinity procedures. Because of their similarities at the regions encoded by either polypeptide, it was concluded that anti-Chs3 antibodies recognized both Chs3 and Chs4 chitin synthases, whereas anti-Chs6 antibodies recognized Chs6 and Chs8 polypeptides. These antibodies were used to analyze the localization of the corresponding chitin synthases in U. maydis cells, using both indirect immunofluorescence microscopy and immunoelectron microscopy with colloidal-gold-labeled secondary antibodies. It was observed that chitin synthase proteins were accumulated both in the surface and in the cytoplasm of the fungal cells. Electron microscopy images revealed the accumulation of clusters of gold particles in vesicles, providing evidence for the possible origin and destination of chitin synthases in the fungal cells. 相似文献
995.
Flad T Mueller L Dihazi H Grigorova V Bogumil R Beck A Thedieck C Mueller GA Kalbacher H Mueller CA 《Proteomics》2006,6(1):364-374
In this study, we describe a differential mass spectrometric technique for the immuno-proteomic analysis of the major histocompatibility complex (MHC) peptides of a renal cell carcinoma (RCC) biopsy compared with the healthy kidney tissue of the same patient after nephrectomy. Using a stable isotope labeling approach, we could directly compare and relatively quantify 43 MHC-peptide pairs, most of which were present in similar proportions on both normal kidney and tumor. Significantly, two dominant peptides of monoisotopic masses ([M+H](+)) 973.43 u and 967.59 u, respectively, were found exclusively in the tumor sample. One of these was identified as originating from heme oxygenase-1 (HO-1), a protein involved in induction of apoptosis resistance, immuno-suppression and neoangiogenesis and reported to be up-regulated in various cancer types. Moreover, the corresponding synthetic HO-1-derived peptide was shown to be immunogenic in vitro by generation of CD8+ T cell lines with peptide-specific cytolytic activity. Thus, this peptide is an example of a differentially identified T cell epitope that could be considered as a target for immunotherapy. 相似文献
996.
An azobenzene group containing beta-amino acid N-Fmoc-4-aminomethyl phenylazobenzoic acid was synthesized and with the exception of the C-terminal amino acid residue was substituted by solid-phase peptide synthesis into all positions of the FLAG sequence (DYKDDDDK), an octapeptide capable of specific interaction with the monoclonal antibody 4E11. The trans state of the beta-amino acid was thermodynamically more stable than the cis state. However, the molecule could be switched into the cis conformation by illumination at 340 nm. Peptides containing the artificial amino acid also became photoresponsive. In the absence of light, the spontaneous back-isomerization into the trans conformation of the photoresponsive was extremely slow (>8 h no significant increase in trans content). When illuminated with visible light (440 nm), the back-isomerization from the cis to the trans state was accelerated and occurred with a half-life of approximately 10 min. The cis form of the photopeptides was more hydrophilic than the trans form, as evidenced by differences in the retention time of the two isomeric forms in reversed-phase chromatography. Photopeptides that contained the intact sequences responsible for binding of the FLAG tag to the antibody, namely, the DYK motive at the N-terminus, showed binding to the antibody in both a dot blot immunoassay and in Biacore binding studies, albeit with lower affinity than the unmodified FLAG sequence. Peptides with a substitution in positions 4-6 showed differences in binding strength between the trans and the cis form in the Biacore studies, no such difference could be observed for the peptide with a substitution in position 7. 相似文献
997.
Gasser RB Hu M Chilton NB Campbell BE Jex AJ Otranto D Cafarchia C Beveridge I Zhu X 《Nature protocols》2006,1(6):3121-3128
The accurate analysis of genetic variation has major implications in many areas of biomedical research, including the identification of infectious agents (such as parasites), the diagnosis of infections, and the detection of unknown or known disease-causing mutations. Mutation scanning methods, including PCR-coupled single-strand conformation polymorphism (SSCP), have significant advantages over many other nucleic acid techniques for the accurate analysis of allelic and mutational sequence variation. The present protocol describes the SSCP method of analysis, including all steps from the small-scale isolation of genomic DNA and PCR amplification of target sequences, through to the gel-based separation of amplicons and scanning for mutations by SSCP (either by the analysis of radiolabeled amplicons in mutation detection enhancement (MDE) gels or by non-isotopic SSCP using precast GMA gels). The subsequent sequence analysis of polymorphic bands isolated from gels is also detailed. The SSCP protocol can readily detect point mutations for amplicon sizes of up to 450-500 bp, and usually takes 1-2 days to carry out. This user-friendly, low-cost, potentially high-throughput platform has demonstrated the utility to study a wide range of pathogens and diseases, and has the potential to be applied to any gene of any organism. 相似文献
998.
Threshold-dependent BMP-mediated repression: a model for a conserved mechanism that patterns the neuroectoderm 总被引:1,自引:0,他引:1
Subdivision of the neuroectoderm into three rows of cells along the dorsal-ventral axis by neural identity genes is a highly conserved developmental process. While neural identity genes are expressed in remarkably similar patterns in vertebrates and invertebrates, previous work suggests that these patterns may be regulated by distinct upstream genetic pathways. Here we ask whether a potential conserved source of positional information provided by the BMP signaling contributes to patterning the neuroectoderm. We have addressed this question in two ways: First, we asked whether BMPs can act as bona fide morphogens to pattern the Drosophila neuroectoderm in a dose-dependent fashion, and second, we examined whether BMPs might act in a similar fashion in patterning the vertebrate neuroectoderm. In this study, we show that graded BMP signaling participates in organizing the neural axis in Drosophila by repressing expression of neural identity genes in a threshold-dependent fashion. We also provide evidence for a similar organizing activity of BMP signaling in chick neural plate explants, which may operate by the same double negative mechanism that acts earlier during neural induction. We propose that BMPs played an ancestral role in patterning the metazoan neuroectoderm by threshold-dependent repression of neural identity genes. 相似文献
999.
1000.
Stefanie F. Geiselhardt Stefan Lamm Claudia Gack Klaus Peschke 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2010,196(5):369-378
Species of various insect orders possess specialised tarsal adhesive structures covered by a thin liquid film, which is deposited
in the form of footprints. This adhesive liquid has been suggested to be chemically and physiologically related to the epicuticular
lipid layer, which naturally covers the body of insects and acts as the prime barrier to environmental stresses, such as desiccation.
The functional efficiency of the layer, however, is jeopardised by partial melting that may occur at physiological temperatures.
In this study, light microscopic images of elytral prints show that the epicuticular lipid layer of the Colorado potato beetle
Leptinotarsa decemlineata actually is partially liquid and chemical investigations reveal the high similarity of the epicuticular hydrocarbon pattern
and the tarsal liquid. By means of chemical manipulation of the surface hydrocarbon composition of live beetles, the substance
exchange between their tarsal adhesive hairs and the body surface is monitored. Histological sections of L. decemlineata tarsi, furthermore, reveal glandular cells connected to individual adhesive setae and departing from these results, an idea
of a general mechanism of tarsal secretion is developed and discussed in a functional–ecological context. 相似文献