Publications by authors named "Toshifumi Tsukahara"

Article Synopsis
  • Researchers successfully demonstrated RNA editing by fusing cytidine deaminase enzymes APOBEC3A and APOBEC3G with the MS2 system to achieve C-to-U editing in RNA.
  • They designed unique guide RNAs that shaped a loop in the target RNA, enabling it to become single-stranded, which enhances the editing process by these enzymes.
  • Although a mutation in APOBEC3G improved its efficiency slightly, the main finding shows that the MS2 system can combine different enzymes for better RNA editing possibilities.
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Adenosine deaminases acting on RNA (ADARs) have double-stranded RNA binding domains and a deaminase domain (DD). We used the MS2 system and specific guide RNAs to direct ADAR1-DD to target adenosines in the mRNA encoding-enhanced green fluorescence protein. Using this system in transfected HEK-293 cells, we evaluated the effects of changing the length and position of the guide RNA on the efficiency of conversion of amber (TAG) and ochre (TAA) stop codons to tryptophan (TGG) in the target.

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Cardiac transcription factors (TFs) directly reprogram fibroblasts into induced cardiomyocytes (iCMs), where MEF2C acts as a pioneer factor with GATA4 and TBX5 (GT). However, the generation of functional and mature iCMs is inefficient, and the molecular mechanisms underlying this process remain largely unknown. Here, we found that the overexpression of transcriptionally activated MEF2C via fusion of the powerful MYOD transactivation domain combined with GT increased the generation of beating iCMs by 30-fold.

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Article Synopsis
  • Long noncoding RNAs (lncRNAs), particularly long exonic noncoding RNAs (lencRNAs), have been linked to genetic abnormalities, but their specific functions are not fully understood.
  • A study employed a tethering luciferase assay to investigate five lencRNAs associated with cancer, revealing that one specific lencRNA interacts with the MED12 component of the CDK8 complex to regulate gene transcription.
  • This lencRNA also influences genes related to fatty acid metabolism and promotes transcription initiation, indicating that it could modulate the activity of nearby genes post-transcription and splicing.
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The restoration of genetic code by editing mutated genes is a potential method for the treatment of genetic diseases/disorders. Genetic disorders are caused by the point mutations of thymine (T) to cytidine (C) or guanosine (G) to adenine (A), for which gene editing (editing of mutated genes) is a promising therapeutic technique. In C-to-Uridine (U) RNA editing, it converts the base C-to-U in RNA molecules and leads to nonsynonymous changes when occurring in coding regions; however, for G-to-A mutations, A-to-I editing occurs.

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Anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor that is genetically altered in several cancers, including NSCLC, melanoma, lymphoma, and other tumors. Although is associated with various cancers, the relationship between expression and patient prognosis in different cancers is poorly understood. Here, using multidimensional approaches, we revealed the correlation between expression and the clinical outcomes of patients with LUAD, melanoma, OV, DLBC, AML, and BC.

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Approval of therapeutic RNA molecules, including RNA vaccines, has paved the way for next-generation treatment strategies for various diseases. Oligonucleotide-based therapeutics hold particular promise for treating incurable muscular dystrophies, including Duchenne muscular dystrophy (DMD). DMD is a severe monogenic disease triggered by deletions, duplications, or point mutations in the gene, which encodes a membrane-linked cytoskeletal protein to protect muscle fibers from contraction-induced injury.

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Purpose: Anaplastic lymphoma kinase (ALK) is an endorsed molecular target in ALK-rearranged carcinomas, including lung adenocarcinoma. However, the clinical advantage of targeting ALK using druggable inhibitors is almost universally restricted by the development of drug resistance. Therefore, a strategy for combating ALK overexpression remains paramount for ALK-driven cancer.

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Cytidine-to-uridine (C-to-U) RNA editing has been generally observed in land plants; however, reverse (U-to-C) RNA editing is a rare phenomenon. In this study, we investigated the U-to-C RNA editing-related genes in Arabidopsis tissues and the effects on mRNA stability, with a special focus on PPR proteins. A previous study showed the extensive occurrence of U-to-C RNA editing in 12-day and 20-dayold Arabidopsis seedlings.

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The popularity and promise of gene therapy for common genetic diseases are currently increasing. Although effective treatments for genetic disorders are rare, editing of the mutated gene is a possible therapeutic approach for conditions caused by stop codon mutations, including either amber (TAG), opal (TGA) or ochre (TAA) stop codons. Restoration of point-mutated RNAs using artificial RNA editing can be used to modify gene-encoded information and generate functionally distinct proteins from a single gene.

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In the present study, the aerial parts of underwent investigation of their in vitro antioxidant and free radical-scavenging activities in cell-free conditions, their phytoconstituents using gas chromatography-mass spectrometry (GC-MS), and their cytotoxic activity in HeLa cells. was extracted with 80% methanol and successively fractionated with solvents to yield petroleum ether (PEF), chloroform (CHF), ethyl acetate (EAF), and aqueous (AQF) fractions. GC-MS analysis revealed that CHF contained ten phytoconstituents, including different forms of octadecanoic acid methyl esters.

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Cytosine-to-Uridine (C-to-U) RNA editing involves the deamination phenomenon, which is observed in animal nucleus and plant organelles; however, it has been considered the U-to-C is confined to the organelles of limited non-angiosperm plant species. Although previous RNA-seq-based analysis implied U-to-C RNA editing events in plant nuclear genes, it has not been broadly accepted due to inadequate confirmatory analyses. Here we examined the U-to-C RNA editing in Arabidopsis tissues at different developmental stages of growth.

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Article Synopsis
  • * The study focused on assessing the stability of Cas13a and guide RNA, optimizing their use, and targeted the v1 transcript in lung cancer cells, achieving significant knockdown of various RNA and protein levels.
  • * Results indicated that Cas13a is effective in reducing cell viability and shows potential for RNA regulation in therapeutics, paving the way for advancements in personalized medicine.
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Many genetic diseases are caused by T-to-C point mutations. Hence, editing of mutated genes represents a promising strategy for treating these disorders. We engineered an artificial RNA editase by combining the deaminase domain of APOBEC1 (apolipoprotein B mRNA editing catalytic polypeptide 1) with a guideRNA (gRNA) which is complementary to target mRNA.

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Two compounds (7--methylmearnsitrin (7-OM) and roseoside A (RA) were identified and characterized from the leaves of (. ) L. The cytotoxicity of 7-OM and RA on HeLa cells was performed using MTT.

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Site-directed RNA editing (SDRE) technologies have great potential for treating genetic diseases caused by point mutations. Our group and other researchers have developed SDRE methods utilizing adenosine deaminases acting on RNA (ADARs) and guide RNAs recruiting ADARs to target RNAs bearing point mutations. In general, efficient SDRE relies on introducing numerous guide RNAs relative to target genes.

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Editing mutated genes is a potential way for the treatment of genetic diseases. G-to-A mutations are common in mammals and can be treated by adenosine-to-inosine (A-to-I) editing, a type of substitutional RNA editing. The molecular mechanism of A-to-I editing involves the hydrolytic deamination of adenosine to an inosine base; this reaction is mediated by RNA-specific deaminases, adenosine deaminases acting on RNA (ADARs), family protein.

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N6-Methyladenosine (m6A) is the most common internal chemical modification of mRNAs involved in many pathological processes including various cancers. In this study, we investigated the role of m6A methyltransferase METTL3 in TGF-β-induced epithelial-mesenchymal transition (EMT) of lung cancer cell lines. The expression of METTL3 and m6A RNA modification were increased during TGF-β-induced EMT of A549 and LC2/ad lung cancer cells.

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Site directed mutagenesis is a very effective approach to recode genetic information. Proper linking of the catalytic domain of the RNA editing enzyme adenosine deaminase acting on RNA (ADAR) to an antisense guide RNA can convert specific adenosines (As) to inosines (Is), with the latter recognized as guanosines (Gs) during the translation process. Efforts have been made to engineer the deaminase domain of ADAR1 and the MS2 system to target specific A residues to restore G→A mutations.

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Following the sequencing of the human genome, SNP analysis of individual patients has become essential for achieving the best drug response and ensuring optimal care. In this study, we developed a cost-effective probes-on-carrier DNA chip for the detection of SNPs. Our chips harbored three different probes against the TP53 gene, and were capable of detecting wild-type TP53 and SNPs such as rs121912651 and rs11540652.

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Alternative splicing is a post- and co-transcriptional regulatory mechanism of gene expression. Pentatricopeptide repeat (PPR) family proteins were recently found to be involved in RNA editing in plants. The aim of this study was to investigate the tissue-specific expression and alternative splicing of PPR family genes and their effects on protein structure and functionality.

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Introduction: Members of the adenosine deaminase acting on RNA (ADAR) family of enzymes consist of double-stranded RNA-binding domains (dsRBDs) and a deaminase domain (DD) that converts adenosine (A) into inosine (I), which acts as guanosine (G) during translation. Using the MS2 system, we engineered the DD of ADAR1 to direct it to a specific target. The aim of this work was to compare the deaminase activities of ADAR1-DD and various isoforms of ADAR2-DD.

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Genetic polymorphisms, including single nucleotide polymorphisms (SNPs), are responsible for inter-individual variability in susceptibility to cancer and other disorders. Both environmental factors (e.g.

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