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Fus-Kujawa A, Mendrek B, Bajdak-Rusinek K, Diak N, Strzelec K, Gutmajster E, Janelt K, Kowalczuk A, Trybus A, Rozwadowska P, Wojakowski W, Gawron K, Sieroń AL. Gene-repaired iPS cells as novel approach for patient with osteogenesis imperfecta. Front Bioeng Biotechnol 2023; 11:1205122. [PMID: 37456734 PMCID: PMC10348904 DOI: 10.3389/fbioe.2023.1205122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 06/21/2023] [Indexed: 07/18/2023] Open
Abstract
Introduction: The benefits of patient's specific cell/gene therapy have been reported in relation to numerous genetic related disorders including osteogenesis imperfecta (OI). In osteogenesis imperfecta particularly also a drug therapy based on the administration of bisphosphonates partially helped to ease the symptoms. Methods: In this controlled trial, fibroblasts derived from patient diagnosed with OI type II have been successfully reprogrammed into induced Pluripotent Stem cells (iPSCs) using Yamanaka factors. Those cells were subjected to repair mutations found in the COL1A1 gene using homologous recombination (HR) approach facilitated with star polymer (STAR) as a carrier of the genetic material. Results: Delivery of the correct linear DNA fragment to the osteogenesis imperfecta patient's cells resulted in the repair of the DNA mutation with an 84% success rate. IPSCs showed 87% viability after STAR treatment and 82% with its polyplex. Discussion: The use of novel polymer Poly[N,N-Dimethylaminoethyl Methacrylate-co-Hydroxyl-Bearing Oligo(Ethylene Glycol) Methacrylate] Arms (P(DMAEMA-co-OEGMA-OH) with star-like structure has been shown as an efficient tool for nucleic acids delivery into cells (Funded by National Science Centre, Contract No. UMO-2020/37/N/NZ2/01125).
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Affiliation(s)
- Agnieszka Fus-Kujawa
- Department of Medical Genetics, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Barbara Mendrek
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Zabrze, Poland
| | - Karolina Bajdak-Rusinek
- Department of Medical Genetics, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Natalia Diak
- Department of Medical Genetics, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Karolina Strzelec
- Department of Molecular Biology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Ewa Gutmajster
- Biotechnology Centre, Silesian University of Technology, Gliwice, Poland
| | - Kamil Janelt
- Department of Medical Genetics, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Agnieszka Kowalczuk
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Zabrze, Poland
| | - Anna Trybus
- Department of Medical Genetics, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
- Students Scientific Society, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Patrycja Rozwadowska
- Department of Medical Genetics, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
- Students Scientific Society, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Wojciech Wojakowski
- Division of Cardiology and Structural Heart Diseases, Medical University of Silesia, Katowice, Poland
| | - Katarzyna Gawron
- Department of Molecular Biology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Aleksander L. Sieroń
- Formerly Department of Molecular Biology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
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Deguchi M, Tsuji S, Katsura D, Kasahara K, Kimura F, Murakami T. Current Overview of Osteogenesis Imperfecta. ACTA ACUST UNITED AC 2021; 57:medicina57050464. [PMID: 34068551 PMCID: PMC8151368 DOI: 10.3390/medicina57050464] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/29/2021] [Accepted: 05/04/2021] [Indexed: 12/18/2022]
Abstract
Osteogenesis imperfecta (OI), or brittle bone disease, is a heterogeneous disorder characterised by bone fragility, multiple fractures, bone deformity, and short stature. OI is a heterogeneous disorder primarily caused by mutations in the genes involved in the production of type 1 collagen. Severe OI is perinatally lethal, while mild OI can sometimes not be recognised until adulthood. Severe or lethal OI can usually be diagnosed using antenatal ultrasound and confirmed by various imaging modalities and genetic testing. The combination of imaging parameters obtained by ultrasound, computed tomography (CT), and magnetic resource imaging (MRI) can not only detect OI accurately but also predict lethality before birth. Moreover, genetic testing, either noninvasive or invasive, can further confirm the diagnosis prenatally. Early and precise diagnoses provide parents with more time to decide on reproductive options. The currently available postnatal treatments for OI are not curative, and individuals with severe OI suffer multiple fractures and bone deformities throughout their lives. In utero mesenchymal stem cell transplantation has been drawing attention as a promising therapy for severe OI, and a clinical trial to assess the safety and efficacy of cell therapy is currently ongoing. In the future, early diagnosis followed by in utero stem cell transplantation should be adopted as a new therapeutic option for severe OI.
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Liu G, Chen J, Zhou Y, Zuo Y, Liu S, Chen W, Wu Z, Wu N. The genetic implication of scoliosis in osteogenesis imperfecta: a review. JOURNAL OF SPINE SURGERY 2017; 3:666-678. [PMID: 29354746 DOI: 10.21037/jss.2017.10.01] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Osteogenesis imperfecta (OI) is a kind of heritable connective tissue disorder, including blue sclerae, hearing loss, skeletal dysplasia causing bone fragility and deformities. It is typically caused by collagen related gene mutations, which could lead to bone formation abnormalities. Scoliosis is one of the most common and severe spinal phenotype which has been reported in approximately 26-74.5% of all OI patients. Recent breakthroughs have suggested that OI can be divided into more than 16 types based on genetic mutations with different degrees of scoliosis. In this review, we summarize the etiology of scoliosis in OI, especially the genetic studies of different types. We aim to provide a systematic review of the genetic etiology and clinical suggestions of scoliosis in OI.
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Affiliation(s)
- Gang Liu
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Jia Chen
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Yangzhong Zhou
- Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China
| | - Yuzhi Zuo
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Sen Liu
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Research Center of Orthopedics/Rare Disease, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Weisheng Chen
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Zhihong Wu
- Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Research Center of Orthopedics/Rare Disease, Chinese Academy of Medical Sciences, Beijing 100730, China.,Department of Central Laboratory, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Nan Wu
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Research Center of Orthopedics/Rare Disease, Chinese Academy of Medical Sciences, Beijing 100730, China
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Xu XJ, Lv F, Liu Y, Wang JY, Song YW, Asan, Wang JW, Song LJ, Jiang Y, Wang O, Xia WB, Xing XP, Li M. A cryptic balanced translocation involving COL1A2 gene disruption cause a rare type of osteogenesis imperfecta. Clin Chim Acta 2016; 460:33-9. [DOI: 10.1016/j.cca.2016.06.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 06/11/2016] [Indexed: 12/25/2022]
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Mantila Roosa SM, Liu Y, Turner CH. Alternative splicing in bone following mechanical loading. Bone 2011; 48:543-51. [PMID: 21095247 PMCID: PMC3039044 DOI: 10.1016/j.bone.2010.11.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 11/05/2010] [Accepted: 11/08/2010] [Indexed: 12/22/2022]
Abstract
It is estimated that more than 90% of human genes express multiple mRNA transcripts due to alternative splicing. Consequently, the proteins produced by different splice variants will likely have different functions and expression levels. Several genes with splice variants are known in bone, with functions that affect osteoblast function and bone formation. The primary goal of this study was to evaluate the extent of alternative splicing in a bone subjected to mechanical loading and subsequent bone formation. We used the rat forelimb loading model, in which the right forelimb was loaded axially for 3 min, while the left forearm served as a non-loaded control. Animals were subjected to loading sessions every day, with 24 h between sessions. Ulnae were sampled at 11 time points, from 4 h to 32days after beginning loading. RNA was isolated and mRNA abundance was measured at each time point using Affymetrix exon arrays (GeneChip® Rat Exon 1.0 ST Arrays). An ANOVA model was used to identify potential alternatively spliced genes across the time course, and five alternatively spliced genes were validated with qPCR: Akap12, Fn1, Pcolce, Sfrp4, and Tpm1. The number of alternatively spliced genes varied with time, ranging from a low of 68 at 12h to a high of 992 at 16d. We identified genes across the time course that encoded proteins with known functions in bone formation, including collagens, matrix proteins, and components of the Wnt/β-catenin and TGF-β signaling pathways. We also identified alternatively spliced genes encoding cytokines, ion channels, muscle-related genes, and solute carriers that do not have a known function in bone formation and represent potentially novel findings. In addition, a functional characterization was performed to categorize the global functions of the alternatively spliced genes in our data set. In conclusion, mechanical loading induces alternative splicing in bone, which may play an important role in the response of bone to mechanical loading.
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Affiliation(s)
- Sara M Mantila Roosa
- Department of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA.
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Abstract
PURPOSE To identify a molecular genetic cause in patients with a clinical diagnosis of osteogenesis imperfecta (OI) type I/IV. METHODS The authors performed multiplex ligation-dependent probe amplification analysis of the COL1A1 gene in a group of 106 index patients. RESULTS In four families with mild osteogenesis imperfecta and no other phenotypic abnormalities, a deletion of the complete COL1A1 gene on one allele was detected, a molecular finding that to our knowledge has not been described before, apart from a larger chromosomal deletion detected by fluorescent in situ hybridization encompassing the COL1A1 gene in a patient with mild osteogenesis imperfecta and other phenotypic abnormalities. Microarray analysis in three of the four families showed that it did not concern a founder mutation. CONCLUSION The clinical picture of complete COL1A1 allele deletions is a comparatively mild type of osteogenesis imperfecta. As such, multiplex ligation-dependent probe amplification analysis of the COL1A1 gene is a useful additional approach to defining the mutation in cases of suspected osteogenesis imperfecta type I with no detectable mutation.
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Rada JAS, Shelton S, Norton TT. The sclera and myopia. Exp Eye Res 2006; 82:185-200. [PMID: 16202407 DOI: 10.1016/j.exer.2005.08.009] [Citation(s) in RCA: 340] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Revised: 08/03/2005] [Accepted: 08/10/2005] [Indexed: 11/28/2022]
Abstract
Myopia is a very common ocular problem, affecting perhaps one billion people worldwide. Most myopia is produced by lengthening of the vitreous chamber of the ocular globe. High myopia is characterized by scleral thinning and localized ectasia of the posterior sclera. The sclera is a dense, fibrous, viscoelastic connective tissue that forms the outer coat of the eye and consists of irregularly arranged lamellae of collagen fibrils interspersed with proteoglycans and non-collagenous glycoproteins. Scleral fibroblasts are located between scleral lamellae, and are responsible for synthesizing the extracellular matrix in which they reside. Research highlighted in this review clearly demonstrates that the sclera is not a static container of the eye, but rather is a dynamic tissue, capable of altering extracellular matrix composition and its biomechanical properties in response to changes in the visual environment to regulate ocular size and refraction. Based on these studies, a strategy directed at reversing myopia-associated scleral extracellular matrix remodeling events would be warranted, particularly in cases of high myopia in humans.
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Affiliation(s)
- Jody A Summers Rada
- Department of Cell Biology, University of Oklahoma Health Science Center, 940 Stanton L. Young Boulevard, BMSB, Room 553, Oklahoma City, 73104, USA.
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Cabral WA, Marini JC. High proportion of mutant osteoblasts is compatible with normal skeletal function in mosaic carriers of osteogenesis imperfecta. Am J Hum Genet 2004; 74:752-60. [PMID: 15024692 PMCID: PMC1181952 DOI: 10.1086/383252] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2003] [Accepted: 01/27/2004] [Indexed: 12/25/2022] Open
Abstract
Individuals with mosaicism for the autosomal dominant bone dysplasia osteogenesis imperfecta (OI) are generally identified by having more than one affected child. The mosaic carriers have both normal and mutant cell populations in somatic and germline tissues but are unaffected or minimally affected by the type I collagen mutation that manifests clinically in their heterozygous offspring. We determined the proportion of mutant osteoblasts in skeletal tissue of two mosaic carriers who each have a COL1A1 mutation in a high proportion of dermal fibroblasts. Both carriers had normal height and bone histology; the first carrier had normal lumbar spine measurements (L1-L4), as determined by dual-energy x-ray absorptiometry (Z = +1.17). In cultured cells from the first carrier, studied by labeled PCR and single-cell PCR over successive passages, the collagen mutation was present in 85% of fibroblasts and 50% and 75% of osteoblasts from her right iliac crest and left patella, respectively, with minimal selection. The second carrier was studied by PCR amplification of DNA from autopsy paraffin blocks. The proportion of heterozygous cells was 40% in calvarium, 65% in tracheal ring, and 70% in aorta. Thus, in OI, substantially normal skeletal growth, density, and histology are compatible with a 40%-75% burden of osteoblasts heterozygous for a COL1A1 mutation. These data are encouraging for mesenchymal stem-cell transplantation, since mosaic carriers are a naturally occurring model for cell therapy.
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Affiliation(s)
- Wayne A Cabral
- Section on Heritable Disorders of Bone, Bone and Extracellular Matrix Branch, National Institute of Child Health and Development, National Institutes of Health, Bethesda, MD 20892, USA
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Roca X, Sachidanandam R, Krainer AR. Intrinsic differences between authentic and cryptic 5' splice sites. Nucleic Acids Res 2003; 31:6321-33. [PMID: 14576320 PMCID: PMC275472 DOI: 10.1093/nar/gkg830] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2003] [Revised: 08/25/2003] [Accepted: 09/11/2003] [Indexed: 11/14/2022] Open
Abstract
Cryptic splice sites are used only when use of a natural splice site is disrupted by mutation. To determine the features that distinguish authentic from cryptic 5' splice sites (5'ss), we systematically analyzed a set of 76 cryptic 5'ss derived from 46 human genes. These cryptic 5'ss have a similar frequency distribution in exons and introns, and are usually located close to the authentic 5'ss. Statistical analysis of the strengths of the 5'ss using the Shapiro and Senapathy matrix revealed that authentic 5'ss have significantly higher score values than cryptic 5'ss, which in turn have higher values than the mutant ones. beta-Globin provides an interesting exception to this rule, so we chose it for detailed experimental analysis in vitro. We found that the sequences of the beta-globin authentic and cryptic 5'ss, but not their surrounding context, determine the correct 5'ss choice, although their respective scores do not reflect this functional difference. Our analysis provides a statistical basis to explain the competitive advantage of authentic over cryptic 5'ss in most cases, and should facilitate the development of tools to reliably predict the effect of disease-associated 5'ss-disrupting mutations at the mRNA level.
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Affiliation(s)
- Xavier Roca
- Cold Spring Harbor Laboratory, PO Box 100, Cold Spring Harbor, NY 11724, USA
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Dawson PA, Kelly TE, Marini JC. Extension of phenotype associated with structural mutations in type I collagen: siblings with juvenile osteoporosis have an alpha2(I)Gly436 --> Arg substitution. J Bone Miner Res 1999; 14:449-55. [PMID: 10027910 DOI: 10.1359/jbmr.1999.14.3.449] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Mutations in the type I collagen genes have been identified as the cause of all four types of osteogenesis imperfecta (OI). We now report a mutation that extends the phenotype associated with structural abnormalities in type I collagen. Two siblings presented with a history of back pain and were diagnosed with juvenile osteoporosis, based on clinical and radiological examination. Radiographs showed decreased lumbar bone density and multiple compression fractures throughout the thoracic and lumbar spines of both patients. One child has moderate short stature and mild neurosensory hearing loss. However, neither child has incurred the long bone fractures characteristic of OI. Protein studies demonstrated electrophoretically abnormal type I collagen in samples from both children. Enzymatic cleavage of RNA:RNA hybrids identified a mismatch in type I collagen alpha2 (COL1A2) mRNA. DNA sequencing of COL1A2 cDNA subclones defined the mismatch as a single-base mutation (1715G --> A) in both children. This mutation predicts the substitution of arginine for glycine at position 436 (G436R) in the helical domain of the alpha2(I) chain. Analysis of genomic DNA identified the mutation in the asymptomatic father, who is presumably a germ-line mosaic carrier. The presence of the same heterozygous mutation in two siblings strongly suggests that the probands display the full phenotype. Taken together, the clinical, biochemical, and molecular findings of this study extend the phenotype associated with type I collagen mutations to cases with only spine manifestations and variable short stature into adolescence.
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Affiliation(s)
- P A Dawson
- Section on Connective Tissue Disorders, Heritable Disorders Branch, National Institute of Child Health and Human Development, Bethesda, Maryland, USA
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Lin CL, Bristol LA, Jin L, Dykes-Hoberg M, Crawford T, Clawson L, Rothstein JD. Aberrant RNA processing in a neurodegenerative disease: the cause for absent EAAT2, a glutamate transporter, in amyotrophic lateral sclerosis. Neuron 1998; 20:589-602. [PMID: 9539131 DOI: 10.1016/s0896-6273(00)80997-6] [Citation(s) in RCA: 482] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that is characterized by selective upper and lower motor neuron degeneration, the pathogenesis of which is unknown. About 60%-70% of sporadic ALS patients have a 30%-95% loss of the astroglial glutamate transporter EAAT2 (excitatory amino acid transporter 2) protein in motor cortex and spinal cord. Loss of EAAT2 leads to increased extracellular glutamate and excitotoxic neuronal degeneration. Multiple abnormal EAAT2 mRNAs, including intron-retention and exon-skipping, have now been identified from the affected areas of ALS patients. The aberrant mRNAs were highly abundant and were found only in neuropathologically affected areas of ALS patients but not in other brain regions. They were found in 65% of sporadic ALS patients but were not found in nonneurologic disease or other disease controls. They were also detectable in the cerebrospinal fluid (CSF) of living ALS patients, early in the disease. In vitro expression studies suggest that proteins translated from these aberrant mRNAs may undergo rapid degradation and/ or produce a dominant negative effect on normal EAAT2 resulting in loss of protein and activity. These findings suggest that the loss of EAAT2 in ALS is due to aberrant mRNA and that these aberrant mRNAs could result from RNA processing errors. Aberrant RNA processing could be important in the pathophysiology of neurodegenerative disease and in excitotoxicity. The presence of these mRNA species in ALS CSF may have diagnostic utility.
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Affiliation(s)
- C L Lin
- Johns Hopkins University, Department of Neurology, Baltimore, Maryland 21287, USA
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Grassi G, Forlino A, Marini JC. Cleavage of collagen RNA transcripts by hammerhead ribozymes in vitro is mutation-specific and shows competitive binding effects. Nucleic Acids Res 1997; 25:3451-8. [PMID: 9254703 PMCID: PMC146924 DOI: 10.1093/nar/25.17.3451] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We report here the in vitro use of hammerhead ribozymes as an approach to the gene therapy of osteogenesis imperfecta (OI). Our strategy for the treatment of this dominant genetic disorder is based on selective reduction of the level of the mRNA transcripts from the mutant allele. We studied the in vitro cleavage activity of five different hammerhead ribozymes targeted against synthetic transcripts of two naturally occurring human collagen mutations and against a point mutation introduced into a construct containing a portion of the mouse COL1A1 gene. This is the first demonstration that ribozyme cleavage is absolutely dependent on the presence of the ribozyme cleavage site introduced by the disease-causing mutation. Cleavage specificity and activity were unchanged when the cleavage site was located in transcripts of progressively longer length. Cleavage efficiency depended directly on the ratio of ribozyme/substrate, as well as on the time and temperature of incubation. We investigated the competitive effects of both total RNA and normal synthetic transcripts on ribozyme cleavage activity. The ribozyme was able to localize and cleave its specific target even in the presence of a vast excess of total RNA. However, cleavage efficiency was linearly inhibited by the presence of a non- cleavable competitor substrate which contained a ribozyme binding site identical to the site present in the cleavable target. Although this competition could be eliminated by introducing a mismatch into one ribozyme binding arm, the presence of the mismatch decreased ribozyme cleavage efficiency. The mutation- specificity of ribozyme cleavage demonstrated in this work provides support for in vivo studies aimed at ribozyme development as a treatment for dominant negative genetic disorders.
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Affiliation(s)
- G Grassi
- Section on Connective Tissue Disorders, Heritable Disorders Branch, National Institutes of Child Health and Human Development, Building 10, Room 9s241, 10 Center Drive, MSC 1830, Bethesda MD 20892-1830, USA
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