The Experts below are selected from a list of 33270 Experts worldwide ranked by ideXlab platform
Rina Rosin-arbesfeld - One of the best experts on this subject based on the ideXlab platform.
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Serum starvation enhances Nonsense Mutation readthrough
Journal of Molecular Medicine, 2019Co-Authors: Amnon Wittenstein, Michal Caspi, Yifat David, Yamit Shorer, Prathamesh T. Nadar-ponniah, Rina Rosin-arbesfeldAbstract:Of all genetic Mutations causing human disease, premature termination codons (PTCs) that result from splicing defaults, insertions, deletions, and point Mutations comprise around 30%. From these Mutations, around 11% are a substitution of a single nucleotide that change a codon into a premature termination codon. These types of Mutations affect several million patients suffering from a large variety of genetic diseases, ranging from relatively common inheritable cancer syndromes to muscular dystrophy or very rare neuro-metabolic disorders. Over the past three decades, genetic and biochemical studies have revealed that certain antibiotics and other synthetic molecules can act as Nonsense Mutation readthrough-inducing drugs. These compounds bind a specific site on the rRNA and, as a result, the stop codon is misread and an amino acid (that may or may not differ from the wild-type amino acid) is inserted and translation occurs through the premature termination codon. This strategy has great therapeutic potential. Unfortunately, many readthrough agents are toxic and cannot be administered over the extended period usually required for the chronic treatment of genetic diseases. Furthermore, readthrough compounds only restore protein production in very few disease models and the readthrough levels are usually low, typically achieving no more than 5% of normal protein expression. Efforts have been made over the years to overcome these obstacles so that readthrough treatment can become clinically relevant. Here, we present the creation of a stable cell line system that constitutively expresses our dual-reporter vector harboring two cancer initiating Nonsense Mutations in the adenomatous polyposis coli (APC) gene. This system will be used as an improved screening method for isolation of new Nonsense Mutation readthrough inducers. Using these cell lines as well as colorectal cancer cell lines, we demonstrate that serum starvation enhances drug-induced readthrough activity, an observation which may prove beneficial in a therapeutic scenario that requires higher levels of the restored protein. Key messages Nonsense Mutations affects millions of people worldwide. We have developed a Nonsense Mutation read-through screening tool. We find that serum starvation enhances antibiotic-induced Nonsense Mutation read-through. Our results suggest new strategies for enhancing Nonsense Mutation read-through that may have positive effects on a large number of patients.
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Serum starvation enhances Nonsense Mutation readthrough
Journal of Molecular Medicine, 2019Co-Authors: Amnon Wittenstein, Michal Caspi, Yifat David, Yamit Shorer, Prathamesh T. Nadar-ponniah, Rina Rosin-arbesfeldAbstract:Of all genetic Mutations causing human disease, premature termination codons (PTCs) that result from splicing defaults, insertions, deletions, and point Mutations comprise around 30%. From these Mutations, around 11% are a substitution of a single nucleotide that change a codon into a premature termination codon. These types of Mutations affect several million patients suffering from a large variety of genetic diseases, ranging from relatively common inheritable cancer syndromes to muscular dystrophy or very rare neuro-metabolic disorders. Over the past three decades, genetic and biochemical studies have revealed that certain antibiotics and other synthetic molecules can act as Nonsense Mutation readthrough-inducing drugs. These compounds bind a specific site on the rRNA and, as a result, the stop codon is misread and an amino acid (that may or may not differ from the wild-type amino acid) is inserted and translation occurs through the premature termination codon. This strategy has great therapeutic potential. Unfortunately, many readthrough agents are toxic and cannot be administered over the extended period usually required for the chronic treatment of genetic diseases. Furthermore, readthrough compounds only restore protein production in very few disease models and the readthrough levels are usually low, typically achieving no more than 5% of normal protein expression. Efforts have been made over the years to overcome these obstacles so that readthrough treatment can become clinically relevant. Here, we present the creation of a stable cell line system that constitutively expresses our dual-reporter vector harboring two cancer initiating Nonsense Mutations in the adenomatous polyposis coli (APC) gene. This system will be used as an improved screening method for isolation of new Nonsense Mutation readthrough inducers. Using these cell lines as well as colorectal cancer cell lines, we demonstrate that serum starvation enhances drug-induced readthrough activity, an observation which may prove beneficial in a therapeutic scenario that requires higher levels of the restored protein.
Michal Caspi - One of the best experts on this subject based on the ideXlab platform.
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Serum starvation enhances Nonsense Mutation readthrough
Journal of Molecular Medicine, 2019Co-Authors: Amnon Wittenstein, Michal Caspi, Yifat David, Yamit Shorer, Prathamesh T. Nadar-ponniah, Rina Rosin-arbesfeldAbstract:Of all genetic Mutations causing human disease, premature termination codons (PTCs) that result from splicing defaults, insertions, deletions, and point Mutations comprise around 30%. From these Mutations, around 11% are a substitution of a single nucleotide that change a codon into a premature termination codon. These types of Mutations affect several million patients suffering from a large variety of genetic diseases, ranging from relatively common inheritable cancer syndromes to muscular dystrophy or very rare neuro-metabolic disorders. Over the past three decades, genetic and biochemical studies have revealed that certain antibiotics and other synthetic molecules can act as Nonsense Mutation readthrough-inducing drugs. These compounds bind a specific site on the rRNA and, as a result, the stop codon is misread and an amino acid (that may or may not differ from the wild-type amino acid) is inserted and translation occurs through the premature termination codon. This strategy has great therapeutic potential. Unfortunately, many readthrough agents are toxic and cannot be administered over the extended period usually required for the chronic treatment of genetic diseases. Furthermore, readthrough compounds only restore protein production in very few disease models and the readthrough levels are usually low, typically achieving no more than 5% of normal protein expression. Efforts have been made over the years to overcome these obstacles so that readthrough treatment can become clinically relevant. Here, we present the creation of a stable cell line system that constitutively expresses our dual-reporter vector harboring two cancer initiating Nonsense Mutations in the adenomatous polyposis coli (APC) gene. This system will be used as an improved screening method for isolation of new Nonsense Mutation readthrough inducers. Using these cell lines as well as colorectal cancer cell lines, we demonstrate that serum starvation enhances drug-induced readthrough activity, an observation which may prove beneficial in a therapeutic scenario that requires higher levels of the restored protein. Key messages Nonsense Mutations affects millions of people worldwide. We have developed a Nonsense Mutation read-through screening tool. We find that serum starvation enhances antibiotic-induced Nonsense Mutation read-through. Our results suggest new strategies for enhancing Nonsense Mutation read-through that may have positive effects on a large number of patients.
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Serum starvation enhances Nonsense Mutation readthrough
Journal of Molecular Medicine, 2019Co-Authors: Amnon Wittenstein, Michal Caspi, Yifat David, Yamit Shorer, Prathamesh T. Nadar-ponniah, Rina Rosin-arbesfeldAbstract:Of all genetic Mutations causing human disease, premature termination codons (PTCs) that result from splicing defaults, insertions, deletions, and point Mutations comprise around 30%. From these Mutations, around 11% are a substitution of a single nucleotide that change a codon into a premature termination codon. These types of Mutations affect several million patients suffering from a large variety of genetic diseases, ranging from relatively common inheritable cancer syndromes to muscular dystrophy or very rare neuro-metabolic disorders. Over the past three decades, genetic and biochemical studies have revealed that certain antibiotics and other synthetic molecules can act as Nonsense Mutation readthrough-inducing drugs. These compounds bind a specific site on the rRNA and, as a result, the stop codon is misread and an amino acid (that may or may not differ from the wild-type amino acid) is inserted and translation occurs through the premature termination codon. This strategy has great therapeutic potential. Unfortunately, many readthrough agents are toxic and cannot be administered over the extended period usually required for the chronic treatment of genetic diseases. Furthermore, readthrough compounds only restore protein production in very few disease models and the readthrough levels are usually low, typically achieving no more than 5% of normal protein expression. Efforts have been made over the years to overcome these obstacles so that readthrough treatment can become clinically relevant. Here, we present the creation of a stable cell line system that constitutively expresses our dual-reporter vector harboring two cancer initiating Nonsense Mutations in the adenomatous polyposis coli (APC) gene. This system will be used as an improved screening method for isolation of new Nonsense Mutation readthrough inducers. Using these cell lines as well as colorectal cancer cell lines, we demonstrate that serum starvation enhances drug-induced readthrough activity, an observation which may prove beneficial in a therapeutic scenario that requires higher levels of the restored protein.
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A flow cytometry-based reporter assay identifies macrolide antibiotics as Nonsense Mutation read-through agents
Journal of Molecular Medicine, 2016Co-Authors: Michal Caspi, Anastasia Firsow, Raja Rajkumar, Nir Skalka, Itay Moshkovitz, Ariel Munitz, Metsada Pasmanik-chor, Hagar Greif, Dalia Megido, Revital KarivAbstract:A large number of human diseases are caused by Nonsense Mutations. These Mutations result in premature protein termination and the expression of truncated, usually nonfunctional products. A promising therapeutic strategy for patients suffering from premature termination codon (PTC)-mediated disorders is to suppress the Nonsense Mutation and restore the expression of the affected protein. Such a suppression approach using specific antibiotics and other read-through promoting agents has been shown to suppress PTCs and restore the production of several important proteins. Here, we report the establishment of a novel, rapid, and very efficient method for screening stop-codon read-through agents. We also show that, in both mammalian cells and in a transgenic mouse model, distinct members of the macrolide antibiotic family can induce read-through of disease-causing stop codons leading to re-expression of several key proteins and to reduced disease phenotypes. Taken together, our results may help in the identification and characterization of well-needed customized pharmaceutical PTC suppression agents. Key messages Establishment of a flow cytometry-based reporter assay to identify Nonsense Mutation read-through agents. Macrolide antibiotics can induce read-through of disease-causing stop codons. Macrolide-induced protein restoration can alleviate disease-like phenotypes.
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erratum to a flow cytometry based reporter assay identifies macrolide antibiotics as Nonsense Mutation read through agents
Journal of Molecular Medicine, 2016Co-Authors: Michal Caspi, Anastasia Firsow, Raja Rajkumar, Nir Skalka, Ariel Munitz, Hagar Greif, Itay Moshkovits, Metsada Pasmanikchor, Dalia Megiddo, Revital KarivAbstract:A large number of human diseases are caused by Nonsense Mutations. These Mutations result in premature protein termination and the expression of truncated, usually nonfunctional products. A promising therapeutic strategy for patients suffering from premature termination codon (PTC)-mediated disorders is to suppress the Nonsense Mutation and restore the expression of the affected protein. Such a suppression approach using specific antibiotics and other read-through promoting agents has been shown to suppress PTCs and restore the production of several important proteins. Here, we report the establishment of a novel, rapid, and very efficient method for screening stop-codon read-through agents. We also show that, in both mammalian cells and in a transgenic mouse model, distinct members of the macrolide antibiotic family can induce read-through of disease-causing stop codons leading to re-expression of several key proteins and to reduced disease phenotypes. Taken together, our results may help in the identification and characterization of well-needed customized pharmaceutical PTC suppression agents.
Amnon Wittenstein - One of the best experts on this subject based on the ideXlab platform.
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Serum starvation enhances Nonsense Mutation readthrough
Journal of Molecular Medicine, 2019Co-Authors: Amnon Wittenstein, Michal Caspi, Yifat David, Yamit Shorer, Prathamesh T. Nadar-ponniah, Rina Rosin-arbesfeldAbstract:Of all genetic Mutations causing human disease, premature termination codons (PTCs) that result from splicing defaults, insertions, deletions, and point Mutations comprise around 30%. From these Mutations, around 11% are a substitution of a single nucleotide that change a codon into a premature termination codon. These types of Mutations affect several million patients suffering from a large variety of genetic diseases, ranging from relatively common inheritable cancer syndromes to muscular dystrophy or very rare neuro-metabolic disorders. Over the past three decades, genetic and biochemical studies have revealed that certain antibiotics and other synthetic molecules can act as Nonsense Mutation readthrough-inducing drugs. These compounds bind a specific site on the rRNA and, as a result, the stop codon is misread and an amino acid (that may or may not differ from the wild-type amino acid) is inserted and translation occurs through the premature termination codon. This strategy has great therapeutic potential. Unfortunately, many readthrough agents are toxic and cannot be administered over the extended period usually required for the chronic treatment of genetic diseases. Furthermore, readthrough compounds only restore protein production in very few disease models and the readthrough levels are usually low, typically achieving no more than 5% of normal protein expression. Efforts have been made over the years to overcome these obstacles so that readthrough treatment can become clinically relevant. Here, we present the creation of a stable cell line system that constitutively expresses our dual-reporter vector harboring two cancer initiating Nonsense Mutations in the adenomatous polyposis coli (APC) gene. This system will be used as an improved screening method for isolation of new Nonsense Mutation readthrough inducers. Using these cell lines as well as colorectal cancer cell lines, we demonstrate that serum starvation enhances drug-induced readthrough activity, an observation which may prove beneficial in a therapeutic scenario that requires higher levels of the restored protein. Key messages Nonsense Mutations affects millions of people worldwide. We have developed a Nonsense Mutation read-through screening tool. We find that serum starvation enhances antibiotic-induced Nonsense Mutation read-through. Our results suggest new strategies for enhancing Nonsense Mutation read-through that may have positive effects on a large number of patients.
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Serum starvation enhances Nonsense Mutation readthrough
Journal of Molecular Medicine, 2019Co-Authors: Amnon Wittenstein, Michal Caspi, Yifat David, Yamit Shorer, Prathamesh T. Nadar-ponniah, Rina Rosin-arbesfeldAbstract:Of all genetic Mutations causing human disease, premature termination codons (PTCs) that result from splicing defaults, insertions, deletions, and point Mutations comprise around 30%. From these Mutations, around 11% are a substitution of a single nucleotide that change a codon into a premature termination codon. These types of Mutations affect several million patients suffering from a large variety of genetic diseases, ranging from relatively common inheritable cancer syndromes to muscular dystrophy or very rare neuro-metabolic disorders. Over the past three decades, genetic and biochemical studies have revealed that certain antibiotics and other synthetic molecules can act as Nonsense Mutation readthrough-inducing drugs. These compounds bind a specific site on the rRNA and, as a result, the stop codon is misread and an amino acid (that may or may not differ from the wild-type amino acid) is inserted and translation occurs through the premature termination codon. This strategy has great therapeutic potential. Unfortunately, many readthrough agents are toxic and cannot be administered over the extended period usually required for the chronic treatment of genetic diseases. Furthermore, readthrough compounds only restore protein production in very few disease models and the readthrough levels are usually low, typically achieving no more than 5% of normal protein expression. Efforts have been made over the years to overcome these obstacles so that readthrough treatment can become clinically relevant. Here, we present the creation of a stable cell line system that constitutively expresses our dual-reporter vector harboring two cancer initiating Nonsense Mutations in the adenomatous polyposis coli (APC) gene. This system will be used as an improved screening method for isolation of new Nonsense Mutation readthrough inducers. Using these cell lines as well as colorectal cancer cell lines, we demonstrate that serum starvation enhances drug-induced readthrough activity, an observation which may prove beneficial in a therapeutic scenario that requires higher levels of the restored protein.
Masafumi Matsuo - One of the best experts on this subject based on the ideXlab platform.
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next generation sequencing discloses a Nonsense Mutation in the dystrophin gene from long preserved dried umbilical cord and low level somatic mosaicism in the proband mother
Journal of Human Genetics, 2016Co-Authors: Mariko Taniguchiikeda, Yasuhiro Takeshima, Mariko Yagi, Masafumi Matsuo, Masahiro Nishiyama, Hiroyuki Awano, Ai Unzaki, Kandai Nozu, Hisahide Nishio, Hiroki KurahashiAbstract:Next-generation sequencing discloses a Nonsense Mutation in the dystrophin gene from long preserved dried umbilical cord and low-level somatic mosaicism in the proband mother
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a Nonsense Mutation created intraexonic splice site is active in the lymphocytes but not in the skeletal muscle of a dmd patient
Human Genetics, 2006Co-Authors: Van Khanh Tran, Yasuhiro Takeshima, Mariko Yagi, Zhujun Zhang, Yasuaki Habara, Kazuhiro Haginoya, Atsushi Nishiyama, Masafumi MatsuoAbstract:Production of semi-functional dystrophin mRNA from the dystrophin gene encoding a premature stop codon has been shown to modify the severe phenotype of Duchenne muscular dystrophy (DMD). In this study, we report the tissue-specific production of semi-functional dystrophin mRNA via activation of a Nonsense Mutation-created intraexonic splice acceptor site. In a DMD patient a novel Nonsense Mutation was identified in exon 42. In his lymphocytes semi-functional dystrophin mRNA with a 63-nucleotide deletion in exon 42 (dys-63) was found to be produced. In vitro splicing assay using hybrid minigenes disclosed that the Mutation-created intraexonic splice acceptor site was activated. In his skeletal muscle cells, however, only the authentically spliced dystrophin mRNA was found. This finding identifies the modulation of the splicing of muscle dystrophin mRNA in cases of DMD as a potential target for therapeutic strategies to generate a milder phenotype for this disease.
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C-terminal truncated dystrophin identified in skeletal muscle of an asymptomatic boy with a novel Nonsense Mutation of the dystrophin gene.
Pediatric Research, 2004Co-Authors: Ryo Suminaga, Yasuhiro Takeshima, Hiroko Wada, Mariko Yagi, Masafumi MatsuoAbstract:Mutations that cause premature stop codons in the dystrophin gene lead to a complete loss of dystrophin from skeletal muscle, resulting in severe Duchenne muscular dystrophy. Here, a C-terminally truncated dystrophin resulting from a novel Nonsense Mutation is shown for the first time to be localized to the muscle plasma membrane. An asymptomatic 8-y-old boy was examined for dystrophin in skeletal muscle because of high serum creatine kinase activity. Remarkably, no dystrophin labeling was seen with an MAb against the C-terminal domain, suggesting the presence of an early stop codon in the dystrophin gene. Labeling with an antibody specific to the N-terminal domain, however, revealed weak, patchy, and discontinuous staining, suggesting limited production of a truncated form of the protein. Molecular analysis revealed a novel Nonsense Mutation (Q3625X) as a result of a single nucleotide change in the patient's genomic DNA (C10873T), leaving 1.6% of dystrophin gene product unsynthesized at the C terminus. Dystrophin mRNA analysis did not show rescue of the Nonsense Mutation as a result of exon-skipping by an alternative splicing mechanism. This is the first report of an asymptomatic dystrophinopathy with a Nonsense Mutation in the dystrophin gene.
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chimeric rna ethylene bridged nucleic acids promote dystrophin expression in myocytes of duchenne muscular dystrophy by inducing skipping of the Nonsense Mutation encoding exon
Human Gene Therapy, 2004Co-Authors: Agus Surono, Yasuhiro Takeshima, Hiroko Wada, Mariko Yagi, Tran Van Khanh, Miho Takagi, Makoto Koizumi, Masafumi MatsuoAbstract:Editing of dystrophin mRNA by induction of exon skipping, using antisense oligonucleotides, has been proposed as one way to generate dystrophin expression in Duchenne muscular dystrophy (DMD) patients. Here, antisense chimeric oligonucleotides consisting of RNA and a new modified nucleic acid are tested for activity to induce skipping of an exon containing a Nonsense Mutation. In a Japanese DMD case, a Nonsense Mutation (R1967X) due to a single nucleotide change in exon 41 of the dystrophin gene (C5899T) was identified. Oligonucleotides consisting of 2′-O-methyl RNA and a new 2′-O,4′-C-ethylene-bridged nucleic acid (ENA) were designed to bind the Mutation site of exon 41, and their ability to induce exon 41 skipping in dystrophin mRNA was evaluated. Finally, among the specific oligonucleotides tested, an 18-mer RNA/ENA chimera was found to have the strongest activity, inducing exon 41 skipping in nearly 90% of dystrophin mRNA. Accordingly, nearly 90% of cultured myocytes were shown to be dystrophin positi...
Kerstin Nagelwolfrum - One of the best experts on this subject based on the ideXlab platform.
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a comparative evaluation of nb30 nb54 and ptc124 in translational read through efficacy for treatment of an ush1c Nonsense Mutation
Embo Molecular Medicine, 2012Co-Authors: Tobias Goldmann, Nora Overlack, Uwe Wolfrum, Fabian Moller, Valery Belakhov, Timor Baasov, Kerstin NagelwolfrumAbstract:Translational read‐through‐inducing drugs (TRIDs) promote read‐through of Nonsense Mutations, placing them in the spotlight of current gene‐based therapeutic research. Here, we compare for the first time the relative efficacies of new‐generation aminoglycosides NB30, NB54 and the chemical compound PTC124 on retinal toxicity and read‐through efficacy of a Nonsense Mutation in the USH1C gene, which encodes the scaffold protein harmonin. This Mutation causes the human Usher syndrome, the most common form of inherited deaf‐blindness. We quantify read‐through efficacy of the TRIDs in cell culture and show the restoration of harmonin function. We do not observe significant differences in the read‐through efficacy of the TRIDs in retinal cultures; however, we show an excellent biocompatibility in retinal cultures with read‐through versus toxicity evidently superior for NB54 and PTC124. In addition, in vivo administration of NB54 and PTC124 induced recovery of the full‐length harmonin a1 with the same efficacy. The high biocompatibilities combined with the sustained read‐through efficacies of these drugs emphasize the potential of NB54 and PTC124 in treating Nonsense Mutation‐based retinal disorders.
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ptc124 mediated translational readthrough of a Nonsense Mutation causing usher syndrome type 1c
Human Gene Therapy, 2011Co-Authors: Tobias Goldmann, Nora Overlack, Uwe Wolfrum, Kerstin NagelwolfrumAbstract:Abstract We investigated the therapeutic potential of the premature termination codon (PTC) readthrough-inducing drug PTC124 in treating the retinal phenotype of Usher syndrome, caused by a Nonsense Mutation in the USH1C gene. Applications in cell culture, organotypic retina cultures, and mice in vivo revealed significant readthrough and the recovery of protein function. In comparison with other readthrough drugs, namely the clinically approved readthrough-inducing aminoglycoside gentamicin, PTC124 exhibits significant better retinal biocompatibility. Its high readthrough efficiency in combination with excellent biocompatibility makes PTC124 a promising therapeutic agent for PTCs in USH1C, as well as other ocular and nonocular genetic diseases.
