• Korean Journal of Animal Reproduction
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• v.27 no.4
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• pp.299-307
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• 2003

The effects of additions/deletions in glycosylated residues of recombinant human EPO (rhEPO) produced in CHO-K1 on their secretion were examined. hEPO cDNA was amplified from human liver mRNA and cloned into the pCR2.1 TOPO. Using overlapping-extension site-directed mutagenesis method, glycosylation sites at 24th, 38th, 83rd, and 126th were respectively or accumulatively removed by substituting its asparagine (or serine) with glutamine. To add novel glycosylation sites, 69 and 105th leucine was mutated to asparagine. Mutant and wild type rhEPO constructs were cloned into the pcDNA3 expression vector with CMV promoter and transfected into CHO cell line, CHO-K1, to produce mutant rhEPO mutant rhEPO proteins. Enzyme-linked immunosorbant assay (ELISA) and Western analysis with monoclonal anti-EPO antibody were performed using supernatants of the cultures showing transient and stable expressions respectively. Addition of novel glycosylation reduced rhEPO secretion dramatically while deletion mutants had little effect except some double deletion mutants ($\Delta$24/83 and $\Delta$38/83) and triple mutant ($\Delta$24/38/83). This fact suggests that not single but combination of changes in glycosyl groups affect secretion of rhEPO in cell culture, possibly via changes in their conformations.

• Clinical and Experimental Pediatrics
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• v.56 no.8
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• pp.355-358
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• 2013

Kabuki syndrome (KS) is a rare genetic disease with a distinctive dysmorphic face, intellectual disability, and multiple congenital abnormalities. KS is inherited in an autosomal dominant manner. As the primary cause of KS, MLL2 mutations have been identified in 56-76% of affected individuals who have been tested, suggesting that there may be additional genes associated with KS. Recently, a few KS individuals have been found to have de novo partial or complete deletions of an X chromosome gene, KDM6A, which encodes a histone demethylase that interacts with MLL2. Nevertheless, mutations in MLL2 are the major cause of KS. Although there are a few reports of KS patients in Korea, none of these had been confirmed by genetic analysis. Here, we report a case of a Korean patient with clinical features of KS. Using direct sequencing, we identified a frameshift heterozygous mutation for MLL2 : (c.5256_5257delGA;p.Lys1753Alafs$^*34$). Clinically, the patient presented with typical facial features, and diagnosis of KS was based on the diagnostic criteria. While KS is a rare disease, other malformations that overlap with those found in individuals with KS are common. Hence, the diagnosis of KS by mutational analysis can be a valuable method for patients with KS-like syndromes. Furthermore, in the near future, other genes could be identified in patients with KS without a detectable MLL2 mutation.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.885-895
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• 2019

Plant biotechnologists have long dreamed of technologies to manipulate genes in plants at will. This dream has come true partly through the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology, which now has been used to edit genes in several important crops. However, there are many restrictions in editing a gene precisely using the CRISPR/Cas9 technology because CRISPR/Cas9 may cause deletions or additions in some regions of the target gene. Several other technologies have been developed for gene targeting and precision editing. Among these, base editors might be the most practically and efficiently used compared to others. Base editors are tools which are able to cause a transition from cytosine into thymine, or from adenine into guanine very precisely on specific sequences. Cytosine base editors basically consist of nCas9, cytosine deaminase, and uracil DNA glycosylase inhibitor (UGI). Adenine base editors consist of nCas9 and adenine deaminase. These were first developed for human cells and have since also been applied successfully to crops. Base editors have been successfully applied for productivity improvement, fortification and herbicide resistance of crops. Thus, base editor technologies start to open a new era for precision gene editing or breeding in crops and might result in revolutionary changes in crop breeding and biotechnology.

• Korean Journal of Plant Tissue Culture
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• v.27 no.5
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• pp.407-409
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• 2000

Outer envelope membrane proteins of chloroplasts encoded by the nuclear genome are transported without the N-terminal transit peptide. Here, we investigated the targeting mechanism of AtOEP7, an Arabidopsis homolog of small outer envelope membrane proteins in vivo. AtOEP7 was expressed transiently in protoplasts or stably in transgenic plants as fusion proteins with GFP. In both cases AtOEP7:GFP was targeted to the outer envelope membrane when assayed under a fluorescent microscope or by Western blot analysis. Except the transmembrane domain, deletions of the N- or C-terminal regions of AtOEP7 did not affect targeting although a region closed to the C-terminal side of the transmembrane domain affected the targeting efficiency. Targeting experiments with various hybrid transmembrane mutants revealed that the amino acid sequence of the transmembrane domain determines the targeting specificity The targeting mechanism was further studied using a fusion protein, AtOEP7：NLS：GFP, that had a nuclear localization signal. AtOEP7：NLS：GFP was efficiently targeted to the chloroplast envelope despite the presence of the nuclear localization signal. Taken together, these results suggest that the transmembrane domain of AtOEP7 functions as the sole determinant of targeting specificity and that AtOEP7 may be associated with a cytosolic component during translocation to the chloroplast envelope membrane.

• Journal of Genetic Medicine
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• v.14 no.2
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• pp.75-79
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• 2017

Duchenne and Becker muscular dystrophies (DMD and BMD, respectively) are X-linked neuromuscular disorders characterized by progressive muscle weakness and severe skeletal muscle degeneration. BMD is a milder form with a later onset. Patients with BMD tend to survive much longer than those with DMD. The differentiation between DMD and BMD is important in the genetic counseling of affected patients and their families. Since muscle biopsies are invasive procedures, the differential diagnosis of BMD and DMD is often dependent on the mutation identified in the DMD gene in affected patients. However, when a novel DMD mutation is identified, the differential diagnosis should be based on muscle biopsy findings with other clinical findings. Here we describe two Korean patients with BMD confirmed by muscle biopsy and genetic testing. Two novel exonic deletions in the DMD gene were identified.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1716-1721
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• 2003

Steroid hormones and their receptors play an important role in reproductive process. Estrogen is intimately involved with pregnancy and its function is mediated through the estrogen receptor which has been chosen as a candidate gene to study litter size in pigs. In this study, we report that two estrogen receptor variants, designated pER-1 and pER-2 were co-expressed in the uteri of normal cycling Lan-Yu pig (Sus vittatus; a small-ear miniature in Taiwan) with the pER-1 expression level appeared to be several times higher than that of pER-2. These receptor variants were isolated using reverse transcription-PCR from the pig uteri and their sequences were determined. The pER-1 and pER-2 sequences, which are homologous to those found in other mammalian estrogen receptors, encode putative proteins consisting of 574 and 486 amino acids, respectively. A deletion in exon I was identified in both sequences, with deletion lengths of 63 bp in pER-1 and 327 bp in pER-2. The deletion in pER-1 is internal to that in pER-2 and both deletions resulted in a truncation of the B domain, which confers the transactivating activity of estrogen receptor protein. This result describes the existence of estrogen receptor variants with a deletion in exon I and implies the possibility that physiological functioning of an estrogen receptor may not require the presence of an intact B domain.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7125-7128
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• 2014

Background: Acquired genetic alterations and presence of sensitizing mutations in the tyrosine kinase domain of EGFR and other signaling molecules have been found in different subsets of primary lung adenocarcinoma. The commonest EGFR mutations are small in frame deletions of exon 19 and a point mutation (L858R) in exon 21, having a combined occurrence of around 90%. The objective of this study was to determine the frequency and types of EGFR mutations in primary lung adenocarcinomas in Pakistan. Materials and Methods: EGFR mutations in tumor samples were screened by multiplex real time PCR. Briefly, DNA from formalin fixed paraffin-embedded tissue was amplified with primers and probes specific to 43 different EGFR mutations in a Cobas z 480 instrument. The assay detects mutations in four exons (18-21) of the EGFR gene. Results: Out of 94 patients, 65 were males and 29 females with a M:F ratio of 2.2: 1. The median age was 62 years (range, 28 - 85 years). In our biopsy samples 70 (74%) cases were of primary lung adenocarcinoma, whereas 24 (26%) were confirmed metastatic adenocarcinoma of primary lung origin. EGFR mutation was positive in 29% of the patients. The highest frequency of L858R was observed in 48% of these, followed by deletion in exon 19 (44%). In addition, other rare mutations such as compound G718X:S768I and insertions in exon 20 insertion were detected in approximately 4% of the patients. Conclusions: This study showed that Del 19 and L858R are the most frequent mutations in Pakistani lung adenocarcinoma patients and around 29% of the patients were found eligible for erlotinib therapy.

• Journal of Gastric Cancer
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• v.20 no.1
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• pp.29-40
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• 2020

Purpose: Gastrointestinal stromal tumors (GISTs) frequently harbor activating gene mutations in either KIT or platelet-derived growth factor receptor A (PDGFRA) and are highly responsive to several selective tyrosine kinase inhibitors. In this study, a targeted next-generation sequencing (NGS) assay with an Oncomine Focus Assay (OFA) panel was used for the genetic characterization of molecular targets in 30 Korean patients with GIST. Materials and Methods: Using the OFA that enables rapid and simultaneous detection of hotspots, single nucleotide variants (SNVs), insertion and deletions (Indels), copy number variants (CNVs), and gene fusions across 52 genes relevant to solid tumors, targeted NGS was performed using genomic DNA extracted from formalin-fixed and paraffin-embedded samples of 30 GISTs. Results: Forty-three hotspot/other likely pathogenic variants (33 SNVs, 8 Indels, and 2 amplifications) in 16 genes were identified in 26 of the 30 GISTs. KIT variants were most frequent (44%, 19/43), followed by 6 variants in PIK3CA, 3 in PDGFRA, 2 each in JAK1 and EGFR, and 1 each in AKT1, ALK, CCND1, CTNNB1, FGFR3, FGFR4, GNA11, GNAQ, JAK3, MET, and SMO. Based on the mutation types, majority of the variants carried missense mutations (60%, 26/43), followed by 8 frameshifts, 6 nonsense, 1 stop-loss, and 2 amplifications. Conclusions: Our study confirmed the advantage of using targeted NGS with a cancer gene panel to efficiently identify mutations associated with GISTs. These findings may provide a molecular genetic basis for developing new drugs targeting these gene mutations for GIST therapy.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.3
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• pp.324-329
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• 2014

To facilitate the construction of genetically-modified pigs, we produced cloned embryos derived from porcine fibroblasts transfected with a pair of engineered zinc finger nuclease (ZFN) plasmids to create targeted mutations and enriched using a reporter plasmid system. The reporter expresses RFP and eGFP simultaneously when ZFN-mediated site-specific mutations occur. Thus, double positive cells ($RFP^+/eGFP^+$) were selected and used for somatic cell nuclear transfer. Two types of reporter based enrichment systems were used in this study; the cloned embryos derived from cells enriched using a magnetic sorting-based system showed better developmental competence than did those derived from cells enriched by flow cytometry. Mutated sequences, such as insertions, deletions, or substitutions, together with the wild-type sequence, were found in the cloned porcine blastocysts. Therefore, genetic mutations can be achieved in cloned porcine embryos reconstructed with ZFN-treated cells that were enriched by a reporter-based system.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2879-2883
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• 2013

Objective: To investigate differences in mutations of epidermal growth factor receptor (EGFR) gene and relationships with clinicopathological features in patients with non-small cell lung cancer (NSCLC) between Uygur and Han ethnic groups. Methods: The Scorpions amplification refractory mutation system (Scorpions ARMS) was used to measure mutations in exons 18, 19, 20 and 21 of the EGFR gene in paraffin-embedded tumor tissue from NSCLC cases, and statistical analysis was performed to investigate links with clinicopathological features in different histological types of NSCLC. Results: Results from ARMS testing showed EGFR mutations in tumor tissues from six (6) of 50 NSCLC patients of Uygur ethnic group, with a positive rate of 12.0%; four of them (4) had exon 19 deletion in EGFR, and two (2) had L858R point mutation in exon 21 of EGFR. Statistically significant difference was noted in EGFR genetic mutation between adenocarcinoma and non-adenocarcinoma (P < 0.05), but no differences with gender, age group, smoking status, or stage (P > 0.05). EGFR mutations were detected in tumor tissues from 27 of 49 NSCLC patients of Han ethnic group, with a positive rate of 55.1%; 19 of them had exon 19 deletions, seven (7) had L858R point mutations in exon 21 of EGFR and one (1) had mutations in both exon 18 G719X and exon 20 T790M of EGFR. Statistically significant differences were noted in EGFR genetic mutations between genders and between adenocarcinoma and non-adenocarcinoma (P<0.05), but not with age group, smoking status, or stage (P > 0.05). Conclusion: Statistically significant differences were noted in the positive rates of EGFR genetic mutations in NSCLC patients between Uygur and Han ethnic groups, with lower positive rates for the Uygur cases.