Search results for "Usher Syndrome"
showing 10 items of 56 documents
The Role of Cadherins in Ca2+-Mediated Cell Adhesion and Inherited Photoreceptor Degeneration
2002
Cadherins are Ca2+-binding, transmembrane proteins involved in cell adhesion. Recently, three cadherin molecules, cadherin-23, protocadherin-15, and cadherin-3, were found to be defective in various human diseases, many of them with photoreceptor degeneration and/or sensorineural hearing loss as major features such Usher syndrome type 1D (USH1D), USH1F, and hypotrichosis with juvenile macular dystrophy. The process, by which mutations lead to photoreceptor degeneration is still not fully understood. Data from the inner ear phenotype of USH1 mouse models suggest that loss of cell adhesion is a crucial event.
Analysis of the Ush2a Gene in Medaka Fish (Oryzias latipes)
2013
Patients suffering from Usher syndrome (USH) exhibit sensorineural hearing loss, retinitis pigmentosa (RP) and, in some cases, vestibular dysfunction. USH is the most common genetic disorder affecting hearing and vision and is included in a group of hereditary pathologies associated with defects in ciliary function known as ciliopathies. This syndrome is clinically classified into three types: USH1, USH2 and USH3. USH2 accounts for well over one-half of all Usher cases and mutations in the USH2A gene are responsible for the majority of USH2 cases, but also for atypical Usher syndrome and recessive non-syndromic RP. Because medaka fish (Oryzias latypes) is an attractive model organism for ge…
Gene Repair of an Usher Syndrome Causing Mutation by Zinc-Finger Nuclease Mediated Homologous Recombination
2012
PURPOSE. Human Usher syndrome (USH) is the most frequent cause of inherited deaf-blindness. It is clinically and genetically heterogeneous, assigned to three clinical types of which the most severe type is USH1. No effective treatment for the ophthalmic component of USH exists. Gene augmentation is an attractive strategy for hereditary retinal diseases. However, several USH genes, like USH1C, are expressed in various isoforms, hampering gene augmentation. As an alternative treatment strategy, we applied the zinc-finger nuclease (ZFN) technology for targeted gene repair of an USH1C, causing mutation by homologous recombination. METHODS. We designed ZFNs customized for the p.R31X nonsense mut…
Usher syndrome and Leber congenital amaurosis are molecularly linked via a novel isoform of the centrosomal ninein-like protein.
2009
Contains fulltext : 80984.pdf (Publisher’s version ) (Closed access) Usher syndrome (USH) and Leber congenital amaurosis (LCA) are autosomal recessive disorders resulting in syndromic and non-syndromic forms of blindness. In order to gain insight into the pathogenic mechanisms underlying retinal degeneration, we searched for interacting proteins of USH2A isoform B (USH2A(isoB)) and the LCA5-encoded protein lebercilin. We identified a novel isoform of the centrosomal ninein-like protein, hereby named Nlp isoform B (Nlp(isoB)), as a common interactor. Although we identified the capacity of this protein to bind calcium with one of its three EF-hand domains, the interacton with USH2A(isoB) did …
Differential Distribution of Harmonin Isoforms and Their Possible Role in Usher-1 Protein Complexes in Mammalian Photoreceptor Cells
2003
PURPOSE. Human Usher syndrome is the most common form of combined deafness and blindness. Usher type I (USH1), the most severe form, is characterized by profound congenital deafness, constant vestibular dysfunction, and prepubertal onset retinitis pigmentosa. Previous studies have shown that the USH1-proteins myosin VIIa, harmonin, and cadherin 23 interact and form a functional network during hair cell differentiation in the inner ear. The purpose of the present study was to analyze the molecular and cellular functions of these USH1 proteins in the mammalian retina. METHODS. Antibodies to USH1 proteins were generated and used in Western blot analysis of subcellular photoreceptor fractions a…
Allelic age of the USH2A c.2299delG mutation
2010
24 p., figuras y bibliografía
The Cellular Function of the Usher Gene Product Myosin VIIa is Specified by Its Ligands
2003
Defects in myosin Vlla are responsible for Usher Syndrome 1B (Weil et al., 1995). Human Usher syndrome (USH), named after the British ophthalmologist Charles Usher (Usher, 1914), is the most common hereditary form of combined blind-and deafness (~ 50% of cases in the developed countries). USH designates a group of clinically and genetically heterogeneous disorders with hearing loss and retinitis pigmentosa (RP). Three different USH types (USH1, 2 and 3; see Table 1) can be distinguished according to the degree of clinical symptomes. USH1 is the most severe subtype, characterized by severe to profound congenital sensorineuronal deafness, constant vestibular dysfunction (balance deficiency) a…
Linkage analysis in Usher syndrome type I (USH1) families from Spain.
1998
Usher syndrome (USH) is an autosomal recessive hereditary disorder characterised by congenital sensorineural hearing loss and gradual visual impairment secondary to retinitis pigmentosa (RP). The disorder is clinically and genetically heterogeneous. With regard to Usher type I (USH1), several subtypes have been described, the most frequent being USH1B located on chromosome 11q13.5. Of 18 USH1 families studied by linkage analysis, 12 (67%) showed significant lod score values for locus D11S527 (Zmax=14.032, theta=0.000) situated on chromosome 11q. Our findings suggest considerable genetic heterogeneity in the Spanish USH1 population. It is important to note that one of our families linked to …
Association of Whirlin with Cav1.3 (α1D) Channels in Photoreceptors, Defining a Novel Member of the Usher Protein Network
2010
Contains fulltext : 88383.pdf (Publisher’s version ) (Closed access) PURPOSE: Usher syndrome is the most common form of hereditary deaf-blindness. It is both clinically and genetically heterogeneous. The USH2D protein whirlin interacts via its PDZ domains with other Usher-associated proteins containing a C-terminal type I PDZ-binding motif. These proteins co-localize with whirlin at the region of the connecting cilium and at the synapse of photoreceptor cells. This study was undertaken to identify novel, Usher syndrome-associated, interacting partners of whirlin and thereby obtain more insights into the function of whirlin. METHODS: The database of ciliary proteins was searched for proteins…
Sequence variants of the DFNB31 gene among Usher syndrome patients of diverse origin.
2010
Contains fulltext : 89306.pdf (Publisher’s version ) (Open Access) PURPOSE: It has been demonstrated that mutations in deafness, autosomal recessive 31 (DFNB31), the gene encoding whirlin, is responsible for nonsyndromic hearing loss (NSHL; DFNB31) and Usher syndrome type II (USH2D). We screened DFNB31 in a large cohort of patients with different clinical subtypes of Usher syndrome (USH) to determine the prevalence of DFNB31 mutations among USH patients. METHODS: DFNB31 was screened in 149 USH2, 29 USH1, six atypical USH, and 11 unclassified USH patients from diverse ethnic backgrounds. Mutation detection was performed by direct sequencing of all coding exons. RESULTS: We identified 38 diff…