Background: BCL6 co-repressor () gene variants are involved in oculofaciocardiodental (OFCD) syndrome, acute myeloid leukaemia, renal tumours, and photoreceptor degenerative diseases. Here, we describe a British family with a pathogenic heterozygous variant in the gene causing congenital nuclear cataract.
Methods: Whole-exome sequencing was conducted on an individual affected by X-linked dominant congenital cataract in a three-generation family to establish the underlying genetic basis.
Eukaryotic cells tether the nucleoskeleton to the cytoskeleton via a conserved molecular bridge, called the LINC complex. The core of the LINC complex comprises SUN-domain and KASH-domain proteins that directly associate within the nuclear envelope lumen. Intra- and inter-chain disulphide bonds, along with KASH-domain protein interactions, both contribute to the tertiary and quaternary structure of vertebrate SUN-domain proteins.
View Article and Find Full Text PDFThe tardigrade Ramazzottius varieornatus has remarkable resilience to a range of environmental stresses. In this study, we have characterised two members of the small heat shock protein (sHSP) family in R. varieornatus, HSP20-3 and HSP20-6.
View Article and Find Full Text PDFIntermediate filaments are critical for cell and tissue homeostasis and for stress responses. Cytoplasmic intermediate filaments form versatile and dynamic assemblies that interconnect cellular organelles, participate in signaling and protect cells and tissues against stress. Here we have focused on their involvement in redox signaling and oxidative stress, which arises in numerous pathophysiological situations.
View Article and Find Full Text PDFRecent studies apparently finding deleterious effects of radiation exposure on cataract formation in birds and voles living near Chernobyl represent a major challenge to current radiation protection regulations. This study conducted an integrated assessment of radiation exposure on cataractogenesis using the most advanced technologies available to assess the cataract status of lenses extracted from fish caught at both Chernobyl in Ukraine and Fukushima in Japan. It was hypothesised that these novel data would reveal positive correlations between radiation dose and early indicators of cataract formation.
View Article and Find Full Text PDFBackground: A five generation family has been analysed by whole exome sequencing (WES) for genetic associations with the multimorbidities of congenital cataract (CC), retinitis pigmentosa (RP) and Crohn's disease (CD).
Methods: WES was performed for unaffected and affected individuals within the family pedigree followed by bioinformatic analyses of these data to identify disease-causing variants with damaging pathogenicity scores.
Results: A novel pathogenic missense variant in : c.
Background: BFSP1 (beaded filament structural protein 1) is a plasma membrane, Aquaporin 0 (AQP0/MIP)-associated intermediate filament protein expressed in the eye lens. BFSP1 is myristoylated, a post-translation modification that requires caspase cleavage at D433. Bioinformatic analyses suggested that the sequences 434-452 were α-helical and amphipathic.
View Article and Find Full Text PDFIonising radiation (IR) is a cause of lipid peroxidation, and epidemiological data have revealed a correlation between exposure to IR and the development of eye lens cataracts. Cataracts remain the leading cause of blindness around the world. The plasma membranes of lens fibre cells are one of the most cholesterolrich membranes in the human body, forming lipid rafts and contributing to the biophysical properties of lens fibre plasma membrane.
View Article and Find Full Text PDFIn the human eye, a transparent cornea and lens combine to form the "refracton" to focus images on the retina. This requires the refracton to have a high refractive index "n," mediated largely by extracellular collagen fibrils in the corneal stroma and the highly concentrated crystallin proteins in the cytoplasm of the lens fiber cells. Transparency is a result of short-range order in the spatial arrangement of corneal collagen fibrils and lens crystallins, generated in part by post-translational modifications (PTMs).
View Article and Find Full Text PDFBackground: Genetically determined cataract is both clinically and molecularly highly heterogeneous. Here, we have identified a heterozygous variant in the lens integral membrane protein LIM2, the second most abundant protein in the lens, responsible for congenital sutural/lamellar cataract in a three-generation Japanese family.
Methods: Whole exome sequencing (WES) was undertaken in one affected and one unaffected individual from a family with autosomal dominant congenital cataract to establish the underlying genetic basis.
Our cluster analysis of the Cancer Genome Atlas for co-expression of HSP27 and CRYAB in breast cancer patients identified three patient groups based on their expression level combination (high HSP27 + low CRYAB; low HSP27 + high CRYAB; similar HSP27 + CRYAB). Our analyses also suggest that there is a statistically significant inverse relationship between HSP27 and CRYAB and known clinicopathological markers in breast cancer. Screening an unbiased 248 breast cancer patient tissue microarray (TMA) for the protein expression of HSP27 and phosphorylated HSP27 (HSP27-82pS) with CRYAB also identified three patient groups based on HSP27 and CRYAB expression levels.
View Article and Find Full Text PDFHuman lens regeneration and the Bag-in-the-Lens (BIL) surgical treatment for cataract both depend upon lens capsule closure for their success. Our studies suggest that the first three days after surgery are critical to their long-term outcomes. Using a rat model of lens regeneration, we evidenced lens epithelial cell (LEC) proliferation increased some 50 fold in the first day before rapidly declining to rates observed in the germinative zone of the contra-lateral, un-operated lens.
View Article and Find Full Text PDFBackground: Congenital cataracts are the most common cause of visual impairment worldwide. Inherited cataract is a clinically and genetically heterogeneous disease. Here we report disease-causing variants in a novel gene, , causing autosomal dominant posterior polar cataract.
View Article and Find Full Text PDFBackground: Lens development is orchestrated by transcription factors. Disease-causing variants in transcription factors and their developmental target genes are associated with congenital cataracts and other eye anomalies.
Methods: Using whole exome sequencing, we identified disease-causing variants in two large British families and one isolated case with autosomal dominant congenital cataract.
Despite the international guidelines on the containment of the coronavirus disease 2019 (COVID-19) pandemic, the European scientific community was not sufficiently prepared to coordinate scientific efforts. To improve preparedness for future pandemics, we have initiated a network of nine European-funded Cooperation in Science and Technology (COST) Actions that can help facilitate inter-, multi-, and trans-disciplinary communication and collaboration.
View Article and Find Full Text PDFBackground: The crystalline lens is mainly composed of a large family of soluble proteins called the crystallins, which are responsible for its development, growth, transparency and refractive index. Disease-causing sequence variants in the crystallins are responsible for nearly 50% of all non-syndromic inherited congenital cataracts, as well as causing cataract associated with other diseases, including myopathies. To date, more than 300 crystallin sequence variants causing cataract have been identified.
View Article and Find Full Text PDFOrgan and tissue development are highly coordinated processes; lens growth and functional integration into the eye (emmetropia) is a robust example. An epithelial monolayer covers the anterior hemisphere of the lens, and its organization is the key to lens formation and its optical properties throughout all life stages. To better understand how the epithelium supports lens function, we have developed a novel whole tissue imaging system using conventional confocal light microscopy and a specialized analysis software to produce three-dimensional maps for the epithelium of intact mouse lenses.
View Article and Find Full Text PDFPediatric cataract is clinically and genetically heterogeneous and is the most common cause of childhood blindness worldwide. In this study, we aimed to identify disease-causing variants in three large British families and one isolated case with autosomal dominant congenital cataract, using whole exome sequencing. We identified four different heterozygous variants, three in the large families and one in the isolated case.
View Article and Find Full Text PDFAlexander disease (AxD) is a fatal neurodegenerative disorder caused by mutations in glial fibrillary acidic protein (GFAP), which supports the structural integrity of astrocytes. Over 70 GFAP missense mutations cause AxD, but the mechanism linking different mutations to disease-relevant phenotypes remains unknown. We used AxD patient brain tissue and induced pluripotent stem cell (iPSC)-derived astrocytes to investigate the hypothesis that AxD-causing mutations perturb key post-translational modifications (PTMs) on GFAP.
View Article and Find Full Text PDFIonizing radiation (IR) damages DNA and other macromolecules, including proteins and lipids. Most cell types can repair DNA damage and cycle continuously their macromolecules as a mechanism to remove defective proteins and lipids. In those cells that lack nuclei and other organelles, such as lens fiber cells and mammalian erythrocytes, IR-induced damage to macromolecules is retained because they cannot be easily replenished.
View Article and Find Full Text PDFBFSP1 (beaded filament structural protein 1, filensin) is a cytoskeletal protein expressed in the eye lens. It binds AQP0 in vitro and its C-terminal sequences have been suggested to regulate the water channel activity of AQP0. A myristoylated fragment from the C-terminus of BFSP1 was found in AQP0 enriched fractions.
View Article and Find Full Text PDFIn the vertebrate eye, limiting oxidation of proteins and lipids is key to maintaining lens function and avoiding cataract formation. A study by Serebryany identifies a surprising contributor to the eye's oxidative defense in their demonstration that γD-crystallin (HγD) functions as an oxidoreductase and uses disulfide exchange to initiate aggregation of mutant crystallins that mimic oxidative damage. These insights suggest a mechanism by which a dynamic pool of closely packed proteins might avoid oxidation-driven protein-folding traps, providing new avenues to understand the basis of a human disease with global impact.
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