• Title/Summary/Keyword: de novo

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Epigenetic Reprogramming in Cloned Embryos

  • Kang, Yong-Kook;Han, Yong-Mahn;Lee, Kyung-Kwang
    • Proceedings of the KSAR Conference
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    • 2001.10a
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    • pp.25-31
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    • 2001
  • During early development, a dramatic reduction in methylation levels occurs in mouse (Monk et al., 1987). The process of epigenetic reprogramming in early embryos erases gamete-specific methylation patterns inherited from the parents (Howlett & Reik 1991, Monk et al., 1987, Oswald et al., 2000, Sanford et al., 1984). This genome-wide demethylation process may be a prerequisite for the formation of pluripotent stem cells that are important for the later development (Reik & Surani 1997). During post-implantation development, a wave of de novo methylation takes place; most of the genomic DNA is methylated at defined developmental timepoints, whereas tissue-specific genes undergo demethylation in their tissues of expression (Kafri et al., 1992, Razin & Kafri 1994). Another demethylation-remethylation cycle of epigenetic reprogramming takes place during gametogenesis and is necessary for resetting of genomic imprinting (Solter 1988). The dynamic epigenetic reprogramming events appear to be basic and are probably conserved in eutherian mammals (see below). (omitted)

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Synthesis and Anti-HIV Activity of Novel 4'-Ethyl-5'-norcarbocyclic Adenosine Phosphonic Acid Analogues

  • Yoo, Jin-Cheol;Li, Hua;Lee, Won-Jae;Hong, Joon-Hee
    • Bulletin of the Korean Chemical Society
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    • v.31 no.11
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    • pp.3348-3352
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    • 2010
  • Novel 4'-ethyl-5'-norcarbocyclic adenosine phosphonic acid analogues were synthesized from propionaldehyde 5 through a de novo acyclic synthetic route using reiterative Grignard additions and ring-closing metathesis (RCM) as key reactions. The synthesized nucleoside phosphonic acids analogues 17, 18, 19, and 21 were subjected to antiviral screening against human immunodeficiency virus.

Development of De Novo Cavernous Hemangioma after Radiosurgery for Cavernous Hemangioma

  • Yeon, Je-Young;Suh, Yeon-Lim;Kim, Jong-Hyun;Lee, Jung-Il
    • Journal of Korean Neurosurgical Society
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    • v.48 no.6
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    • pp.532-533
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    • 2010
  • We report a rare case of cavernous hemangioma (CH) which developed in adjacent location to a preexisting CH after gamma knife radiosurgery (GKRS). A 36-year-old woman underwent GKRS for a CH in the left lentiform nucleus. Three-and-half years after radiosurgery, MRI revealed a new CH in the left caudate nucleus. Surgical excision of the new lesion was performed. The pathological examination confirmed the diagnosis of CH. In radiosurgery for CH, it should be noted that a new CH may develop, which is likely to result from the interaction between radiation and predisposing factors of the patient.

Diagnostic approach for genetic causes of intellectual disability

  • Yim, Shin-Young
    • Journal of Genetic Medicine
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    • v.12 no.1
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    • pp.6-11
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    • 2015
  • Intellectual disability (ID) is the most common disability among people under the age of 20 years. In the absence of obvious non-genetic causes of ID, the majority of cases of severe ID are thought to have a genetic cause. The advent of technologies such as array comparative genomic hybridization, single nucleotide polymorphism genotyping arrays, and massively parallel sequencing has shown that de novo copy number variations and single nucleotide variations affecting coding regions are major causes of severe ID. This article reviews the genetic causes of ID along with diagnostic approaches for this disability.

Inhibition of 5α-reductase of de novo Generation of Short Anti-oxidant Peptides

  • Lee, Sung-Gyu;Kang, Hyun
    • Biomedical Science Letters
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    • v.24 no.3
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    • pp.263-269
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    • 2018
  • This study aims to investigate the biological activities related to hair loss of short anti-oxidant peptides (DK peptides) $5{\alpha}$-reductase inhibition and anti-oxidation. The series of DK peptides were generated amphipathic helical properties using leucines, lysines and tryptophan residues. Cell viability and free radical scavenging activities were performed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The DK peptides were investigated for inhibitory activity against $5{\alpha}$-reductase. Antioxidant activities were determined by means of, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assays. All peptides could inhibit $5{\alpha}$-reductase in lipopolysaccharide-stimulated macrophage. In conclusion, DK peptides was suggested as the most attractive ingredients for improving hair loss, because of the high inhibitory against $5{\alpha}$-reductase inhibition.

REGULATION OF PROENKEPHALIN GENE EXPRESSION AND MET-ENKEPHALIN SECRETION IN BOVINE ADRENAL MEDULLARY CHROMAFFIN CELLS AND C6 RAT GLIOMA CELLS

  • Suh, Hong-Won
    • Toxicological Research
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    • v.9 no.2
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    • pp.195-206
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    • 1993
  • The expression of proenkephalin (proENK) mRNA and Met-enkephalin (ME) secretion in C6 rat glioma cells and bovine adrenal medullary chromaffin (BAMC) cells were elucidated in the present study. The levels of proENK mRNA and ME secreted into the media in BAMC cells were measured in the presence of cycloheximide and 12-tetrade-canoylphorbol-13-acetate (TPA). Cycloheximide (20 nM) abolished the induction of proENK mRNA expression, protein synthesis and ME secretion by TPA (1nM), indicating that de novo protein synthesis was necessary for proENK gene expression and ME secretion.

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High-throughput identification of chrysanthemum gene function and expression: An overview and an effective proposition

  • Nguyen, Toan Khac;Lim, Jin Hee
    • Journal of Plant Biotechnology
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    • v.48 no.3
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    • pp.139-147
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    • 2021
  • Since whole-genome duplication (WGD) of diploid Chrysanthemum nankingense and de novo assembly whole-genome of C. seticuspe have been obtained, they have afforded to perceive the diversity evolution and gene discovery in the improved investigation of chrysanthemum breeding. The robust tools of high-throughput identification and analysis of gene function and expression produce their vast importance in chrysanthemum genomics. However, the gigantic genome size and heterozygosity are also mentioned as the major obstacles preventing the chrysanthemum breeding practices and functional genomics analysis. Nonetheless, some of technological contemporaries provide scientific efficient and promising solutions to diminish the drawbacks and investigate the high proficient methods for generous phenotyping data obtaining and system progress in future perspectives. This review provides valuable strategies for a broad overview about the high-throughput identification, and molecular analysis of gene function and expression in chrysanthemum. We also contribute the efficient proposition about specific protocols for considering chrysanthemum genes. In further perspective, the proper high-throughput identification will continue to advance rapidly and advertise the next generation in chrysanthemum breeding.

Complete genome sequence of Clostridium perfringens B20, a bacteriocin-producing pathogen

  • Elnar, Arxel G.;Kim, Geun-Bae
    • Journal of Animal Science and Technology
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    • v.63 no.6
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    • pp.1468-1472
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    • 2021
  • Clostridium perfringens B20 was isolated from chicken feces collected from a local farm associated with Chung-Ang University (Anseong, Korea). The whole genome of C. perfringens B20 was sequenced using the PacBio RS II platform and assembled de novo. The genome is 2,982,563 bp long and assembled in two contigs. Annotation analyses revealed 2,668 protein-coding sequences, 30 rRNA genes, and 94 tRNA genes, with 28.2% G + C (guanine + cytosine) content. In silico genomic analysis revealed the presence of genes encoding a class IId bacteriocin, lactococcin A, and associated ABC transporter and immunity proteins, as well as a putative bacteriocin gene.

Genome-Wide Comparison of Carbohydrate-Active Enzymes (CAZymes) Repertoire of Flammulina ononidis

  • Park, Young-Jin;Kong, Won-Sik
    • Mycobiology
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    • v.46 no.4
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    • pp.349-360
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    • 2018
  • Whole-genome sequencing of Flammulina ononidis, a wood-rotting basidiomycete, was performed to identify genes associated with carbohydrate-active enzymes (CAZymes). A total of 12,586 gene structures with an average length of 2009 bp were predicted by the AUGUSTUS tool from a total 35,524,258 bp length of de novo genome assembly (49.76% GC). Orthologous analysis with other fungal species revealed that 7051 groups contained at least one F. ononidis gene. In addition, 11,252 (89.5%) of 12,586 genes for F. ononidis proteins had orthologs among the Dikarya, and F. ononidis contained 8 species-specific genes, of which 5 genes were paralogous. CAZyme prediction revealed 524 CAZyme genes, including 228 for glycoside hydrolases, 21 for polysaccharide lyases, 87 for glycosyltransferases, 61 for carbohydrate esterases, 87 with auxiliary activities, and 40 for carbohydrate-binding modules in the F. ononidis genome. This genome information including CAZyme repertoire will be useful to understand lignocellulolytic machinery of this white rot fungus F. ononidis.

A frameshift mutation in the TRPS1 gene showing a mild phenotype of trichorhinophalangeal syndrome type 1

  • Park, Jin-Mo;Lee, Yun Jeong;Park, Jin-Sung
    • Journal of Genetic Medicine
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    • v.15 no.2
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    • pp.97-101
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    • 2018
  • Tricho-rhino-phalangeal syndrome (TRPS) is a hereditary disorder characterized by craniofacial and skeletal abnormalities. A mutation of the TRPS1 gene leads to TRPS type I or type III. A 20-year-old male patient visited our neurologic department with chronic fatigue. He presented with short stature, sparse hair, pear-shaped nose, and brachydactyly. Radiologic study showed short metacarpals, metatarsals with cone-shaped epiphyses, hypoplastic femur and hip joint. Panel sequencing for OMIM (Online Mendelian Inheritance in Man) listed genes revealed a de novo heterozygous frameshift mutation of c.1801_1802delGA (p.Arg601Lysfs*3) of exon 4 of the TRPS1 gene. The diagnosis of TRPS can be challenging due to the rarity and variable phenotype of the disease, clinicians should be aware of its characteristic clinical features that will lead a higher rate of diagnosis.