Search results for "Presentation"
showing 10 items of 2405 documents
COMPLEX STRUCTURES ON INDECOMPOSABLE 6-DIMENSIONAL NILPOTENT REAL LIE ALGEBRAS
2007
We compute all complex structures on indecomposable 6-dimensional real Lie algebras and their equivalence classes. We also give for each of them a global holomorphic chart on the connected simply connected Lie group associated to the real Lie algebra and write down the multiplication in that chart.
On invariant measures of finite affine type tilings
2006
In this paper, we consider tilings of the hyperbolic 2-space, built with a finite number of polygonal tiles, up to affine transformation. To such a tiling T, we associate a space of tilings: the continuous hull Omega(T) on which the affine group acts. This space Omega(T) inherits a solenoid structure whose leaves correspond to the orbits of the affine group. First we prove the finite harmonic measures of this laminated space correspond to finite invariant measures for the affine group action. Then we give a complete combinatorial description of these finite invariant measures. Finally we give examples with an arbitrary number of ergodic invariant probability measures.
Poisson Geometry in Mathematics and Physics
2008
We realize quantized anti de Sitter space black holes, building Connes spectral triples, similar to those used for quantized spheres but based on Universal Deformation Quantization Formulas (UDF) obtained from an oscillatory integral kernel on an appropriate symplectic symmetric space. More precisely we first obtain a UDF for Lie subgroups acting on a symplectic symmetric space M in a locally simply transitive manner. Then, observing that a curvature contraction canonically relates anti de Sitter geometry to the geometry of symplectic symmetric spaces, we use that UDF to define what we call Dirac-isospectral noncommutative deformations of the spectral triples of locally anti de Sitter black…
Human cytomegalovirus US3 modulates destruction of MHC class I molecules
2012
Human cytomegalovirus (HCMV), a member of the Herpesviridae family, is proficient at establishing lifelong persistence within the host in part due to immune modulating genes that limit immune recognition. HCMV encodes at least five glycoproteins within its unique short (US) genomic region that interfere with MHC class I antigen presentation, thus hindering viral clearance by cytotoxic T lymphocytes (CTL). Specifically, US3 retains class I within the endoplasmic reticulum (ER), while US2 and US11 induce class I heavy chain destruction. A cooperative effect on class I down-regulation during stable expression of HCMV US2 and US3 has been established. To address the impact of US3 on US11-mediat…
Identification of sequences in the human peptide transporter subunit TAP1 required for transporter associated with antigen processing (TAP) function
2001
The heterodimeric peptide transporter associated with antigen processing (TAP) consisting of the subunits TAP1 and TAP2 mediates the transport of cytosolic peptides into the lumen of the endoplasmic reticulum (ER). In order to accurately define domains required for peptide transporter function, a molecular approach based on the construction of a panel of human TAP1 mutants and their expression in TAP1(-/-) cells was employed. The characteristics and biological activity of the various TAP1 mutants were determined, and compared to that of wild-type TAP1 and TAP1(-/-) control cells. All mutant TAP1 proteins were localized in the ER and were capable of forming complexes with the TAP2 subunit. H…
A high-throughput genome-wide siRNA screen for ciliogenesis identifies new ciliary functional components and ciliopathy genes.
2015
Defects in primary cilium biogenesis underlie the ciliopathies, a growing group of genetic disorders. We describe the first whole genome siRNA-based reverse genetics screen for defects in biogenesis and/or maintenance of the primary cilium, obtaining a global resource for investigation and interventions into the processes that are critical for the ciliary system. In total, we identified 83 candidate ciliogenesis and ciliopathy genes, including 15 components of the ubiquitin-proteasome system. The validated hits also include 12 encoding G-protein-coupled receptors, and three encoding pre-mRNA processing factors (PRPF6, PRPF8 and PRPF31) mutated in autosomal dominant retinitis pigmentosa. Com…
Major Histocompatibility Complex Polymorphisms and Ageing.
2004
ASTRACT Longevity seems to be directly correlated with optimal functioning of the immune system, suggesting that some genetic determinants of longevity might reside in those polymorphisms for the immune system genes that regulate immune responses. Accordingly, mouse lifespan is influenced by MHC (major histocompatibility complex) genotype. The HLA (the human MHC) region encompasses over 4 Mb of DNA on the chromosome band 6p21.3 and its extensive characterisation has recently culminated in the determination of the nucleotide sequence of the entire region, confirming the presence of ~ 220 genes. The MHC is traditionally divided into the class I, class II and class III regions. Most HLA genes …
Transgenic tools for proteomic analysis of ciliary transport
2015
Vision begins as photons are captured by photoreceptor cilia and light is converted into electrical signals that are then sent to the brain. As the photoreceptor cilium is not able to make its own proteins, all polypeptides needed for converting photons into electrical signals are synthetized in the cell body. How these molecules move from the cell body to cilia is still unclear. Opsin is one of the best-characterized transmembrane proteins. Our goal is to understand the mechanism of opsin transport into photoreceptor cilia. In this project, we use a combination of genetic and proteomic approaches in the zebrafish model. As the first step, we are constructing a transgenic line that expresse…
Identification of novel interaction partners for Vlgr1b/GPR98 - a key component of the periciliary Usher syndrome protein network in photoreceptor ce…
2012
The human Usher syndrome (USH) is the most common form of combined hereditary deaf-blindness. Three clinical subtypes (USH1-3) are differentiated based on severity, age of onset and progression of the symptoms. Mutations in the GPR98 gene encoding the USH2C protein Vlgr1b or GPR98 cause USH2, the most common form of USH. The G-protein coupled receptor Vlgr1b was previously identified as a component of the periciliary USH protein network, crucial for ciliary cargo transport in photoreceptors. Nonetheless, the exact role of Vlgr1b in this and other cellular processes remains to be elucidated. To learn more about its involvement in cellular functions we searched for novel interaction partners …
Topological Hopf Algebras, Quantum Groups and Deformation Quantization
2019
After a presentation of the context and a brief reminder of deformation quantization, we indicate how the introduction of natural topological vector space topologi es on Hopf algebras associated with Poisson Lie groups, Lie bialgebras and their doubles explains their dualities a nd provides a comprehensive framework. Relations with deformation quantization and applications to the deformation quantization of symmetric spaces are described.