• Annals of Clinical Neurophysiology
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• v.14 no.2
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• pp.53-58
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• 2012

For the last decades, molecular genetics has achieved great advances that the genes on the list of inherited muscle diseases are piling up. Those diseases of overlapping clinico-pathologic findings are now understood with discrete molecular pathogeneses. We are facing an exciting era that the long-waited gene therapy may eventually come true. Skipping of dystrophin exon 51 is on successful clinical trials, which will benefit about 13% of the children suffering from Duchenne muscular dystrophy. Exon skipping is under active investigation to expand the candidates. Hopefully it may cover majority of Duchenne muscular dystrophy mutations and some of other diseases. Adeno-associated virus is one of the most versatile tools for gene transfer. It may overcome the limitation of exon skipping. Here we review exon skipping technique of Duchenne muscular dystrophy and briefly discuss the other strategies being studied to cure inherited muscle diseases.

• Biomolecules & Therapeutics
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• v.31 no.4
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• pp.466-472
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• 2023

Exon skipping is an efficient technique to inhibit specific gene expression induced by a short-sequence peptide nucleic acid (PNA). To date, there has been no study on the effects of PNA on skin pigmentation. In melanocytes, the tripartite complex is responsible for the transport of mature melanosomes from the nucleus to the dendrites. The tripartite complex is composed of Rab27a, Mlph (Melanophilin), and Myosin Va. Defects in the protein Mlph, a melanosome transport-related protein, are known to cause hypopigmentation. Our study shows that Olipass peptide nucleic acid (OPNA), a cell membrane-permeable PNA, targets exon skipping in the Mlph SHD domain, which is involved in Rab27a binding. Our findings demonstrate that OPNA induced exon skipping in melan-a cells, resulting in shortened Mlph mRNA, reduced Mlph protein levels, and melanosome aggregation, as observed by microscopy. Therefore, OPNA inhibits the expression of Mlph by inducing exon skipping within the gene. These results suggest that OPNA, which targets Mlph, may be a potential new whitening agent to inhibit melanosome movement.

• Journal of Genetic Medicine
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• v.11 no.1
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• pp.40-42
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• 2014

Neurofibromatosis type 1 (NF1) is an autosomal dominant disease characterized by neurological, cutaneous, and ophthalmological manifestations. A 33-year-old woman with typical symptoms of NF1 visited Ajou University Hospital. Screening of the whole-messenger RNA region of NF1 at the complementary DNA level by polymerase chain reaction-direct sequencing confirmed the presence of an NF1 mutation at the genomic level. The mutation analysis revealed an in-frame skipping of exon 46 (c.6757_6858del) caused by a point mutation (c. 6792C>A) in exon 46. In this report, we have described the first Korean case of a proband with NF1 that carries an allele with an exon 46 deletion caused by an exonic splicing enhancer site mutation, leading to the skipping of the whole of exon 46 (c.6757_6858del).

• Journal of Interdisciplinary Genomics
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• v.1 no.1
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• pp.1-5
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• 2019

Progressive weakness of skeletal muscle is the hallmark of muscular dystrophies. It is often accompanied by cardiomyopathy and respiratory insufficiency. It has generally been perceived as incurable diseases, while the advent of genetic therapy is changing the paradigm. Most research and achievements have been for the treatment of Duchenne muscular dystrophy, while it is promising to hope for therapies for other myopathies. Drugs for nonsense read-through and exon skipping are already approved for clinical use in Europe and the United States, respectively. Gene therapy using adeno-associated virus is in early phase of clinical trial. In this review, most promising genetic therapies will be briefly described.

• Molecules and Cells
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• v.23 no.2
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• pp.228-238
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• 2007

Since molecular structure of hnRNP is not available in foreseeable future, it is best to construct a working model for hnRNP structure. A geometric problem, assembly of $700{\pm}20$ nucleotides with 48 proteins, is visualized by a frame work in which all the proteins participate in primary binding, followed by secondary, tertiary and quaternary binding with neighboring proteins without additional import. Thus, 40S hnRNP contains crown-like secondary structure (48 stemloops) and appearance of 6 petal (octamers) rose-like architectures. The proteins are wrapped by RNA. Co-transcriptional folding for RNP fibril of FMR1 gene can produce 2,571 stem-loops with frequency of 1 stem-loop/15.3 nucleotides and 53 40S hnRNP beaded structure. By spliceosome driven reactions, there occurs removal of 16 separate lariated RNPs, joining 17 separate beaded exonic structures and anchoring EJC on each exon junction. Skipping exon 12 has 5'GU, 3'AG and very compact folding pattern with frequency of 1 stem-loop per 12 nucleotides in short exon length (63 nucleotides). 5' end of exon 12 contains SS (Splicing Silencer) element of UAGGU. In exons 10, 15 and 17 where both regular and alternative splice sites exist, SS (hnRNP A1 binding site) is observed at the regular splicing site. End products are mature FMR-1 mRNP, 4 species of Pri-microRNAs derived from introns 7,9,15 and 3'UTR of exon17, respectively. There may also be some other regulatory RNAs containing ALU/Line elements as well.

• Molecules and Cells
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• v.38 no.11
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• pp.950-958
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• 2015

BCS1L gene encodes mitochondrial protein and is a member of conserved AAA protein family. This gene is involved in the incorporation of Rieske FeS and Qcr10p into complex III of respiratory chain. In our previous study, AluYRa2-derived alternative transcript in rhesus monkey genome was identified. However, this transcript has not been reported in human genome. In present study, we conducted evolutionary analysis of AluYRa2-exonized transcript with various primate genomic DNAs and cDNAs from humans, rhesus monkeys, and crabeating monkeys. Remarkably, our results show that AluYRa2 element has only been integrated into genomes of Macaca species. This Macaca lineage-specific integration of AluYRa2 element led to exonization event in the first intron region of BCS1L gene by producing a conserved 3' splice site. Intriguingly, in rhesus and crabeating monkeys, more diverse transcript variants by alternative splicing (AS) events, including exon skipping and different 5' splice sites from humans, were identified. Alignment of amino acid sequences revealed that AluYRa2-exonized transcript has short N-terminal peptides. Therefore, AS events play a major role in the generation of various transcripts and proteins during primate evolution. In particular, lineage-specific integration of Alu elements and species-specific Alu-derived exonization events could be important sources of gene diversification in primates.

• Journal of Periodontal and Implant Science
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• v.45 no.2
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• pp.69-75
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• 2015

Purpose: Salivary fluid formation is primarily driven by Ca2+-activated, apical efflux of chloride into the lumen of the salivary acinus. The anoctamin1 protein is an anion channel with properties resembling the endogenous calcium-activated chloride channels. In order to better understand the role of anoctamin proteins in salivary exocrine secretion, the expression of the ten members of the anoctamin gene family in the mouse submandibular gland was studied. Methods: Total RNA extracted from mouse submandibular salivary glands was reverse transcribed using primer pairs to amplify the full-length coding regions of each anoctamin gene and was subcloned into plasmid vectors for DNA sequencing. Alternative splice variants were also screened by polymerase chain reaction using primer pairs that amplified six overlapping regions of the complementary DNA of each anoctamin gene, spanning multiple exons. Results: Multiple anoctamin transcripts were found in the mouse submandibular salivary gland, including full-length transcripts of anoctamin1, anoctamin3, anoctamin4, anoctamin5, anoctamin6, anoctamin9, and anoctamin10. Exon-skipping splicing in the N-terminal exons of the anoctamins1, anoctamin5, and anoctamin6 genes resulted in multiple alternative splice variants. No expression of anoctamin2, anoctamin7, or anoctamin8 was found. Conclusions: The predominant anoctamin transcript expressed in the mouse submandibular gland is anoctamin1ac. The chloride channel protein produced by anoctamin1ac is likely responsible for the $Ca^{2+}$-activated chloride efflux, which is the rate-limiting step in salivary exocrine secretion.