• 대한치과교정학회지
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• 제29권5호
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• pp.511-519
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• 1999

생역학적으로 우수한 스프링을 설계하기 위해서 스프링의 형태에 여러 가지 변화를 주면서 각 상황에서 force system이 변하는 양상을 수치분석계산과 spring tester를 이용한 실험과 비교하였다. 주어진 해부학적인 한계 내에서 최대한 생역학적 효율을 높이는 요소들을 제시하였다. 1. 스프링의 높이가 증가하면 M/F ratio는 증가하고 L/D rate은 감소한다. 2. 스프링의 최소 굽힘 모멘트 부위보다 위에 wire를 첨가하면 M/F ratio는 증가하고 L/D rate은 감소한다. 3. 스프링의 최소 굽힘 모멘트 부위보다 아래에 wire를 첨가하면 M/F ratio는 감소하고 L/D rate도 감소한다. 4. 스프링의 위쪽에 아무리 wire를 많이 첨가하여도 스프링의 높이 이상의 M/F ratio는 얻을 수 없다. 5. 제한된 높이의 스프링으로 충분한 M/F ratio를 얻기 위해서는 부가적인 모멘트가 필요하다. 6. 스프링의 수평 길이가 증가할 수록 M/F ratio와 L/D rate는 감소하므로 부가적인 모멘트는 점점 각도가 증가할 수 있도록 스프링 전체에 부여할 필요가 있다. 7. L/D rate는 재료, 단면, 그리고 형태에 영향을 받지만 M/F ratio는 재료나 단면에 관계없이 스프링의 형태에만 영향을 받는다.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2001년도 Proceedings of 2001 International Symposium
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• pp.83-89
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• 2001

Recent advances in the structural and molecular biology uncovered that a set of translation factors resembles a tRNA shape and, in one case, even mimics a tRNA function for deciphering the genetic ：ode. Nature must have evolved this 'art' of molecular mimicry between protein and ribonucleic acid using different protein architectures to fulfill the requirement of a ribosome 'machine'. Termination of protein synthesis takes place on the ribosomes as a response to a stop, rather than a sense, codon in the 'decoding' site (A site). Translation termination requires two classes of polypeptide release factors (RFs)： a class-I factor, codon-specific RFs (RFI and RF2 in prokaryotes; eRFI in eukaryotes), and a class-IT factor, non-specific RFs (RF3 in prokaryotes; eRF3 in eukaryotes) that bind guanine nucleotides and stimulate class-I RF activity. The underlying mechanism for translation termination represents a long-standing coding problem of considerable interest since it entails protein-RNA recognition instead of the well-understood codon-anticodon pairing during the mRNA-tRNA interaction. Molecular mimicry between protein and nucleic acid is a novel concept in biology, proposed in 1995 from three crystallographic discoveries, one, on protein-RNA mimicry, and the other two, on protein-DNA mimicry. Nyborg, Clark and colleagues have first described this concept when they solved the crystal structure of elongation factor EF- Tu：GTP：aminoacyl-tRNA ternary complex and found its overall structural similarity with another elongation factor EF-G including the resemblance of part of EF-G to the anticodon stem of tRNA (Nissen et al. 1995). Protein mimicry of DNA has been shown in the crystal structure of the uracil-DNA glycosylase-uracil glycosylase inhibitor protein complex (Mol et al. 1995; Savva and Pear 1995) as well as in the NMR structure of transcription factor TBP-TA $F_{II}$ 230 complex (Liu et al. 1998). Consistent with this discovery, functional mimicry of a major autoantigenic epitope of the human insulin receptor by RNA has been suggested (Doudna et al. 1995) but its nature of mimic is. still largely unknown. The milestone of functional mimicry between protein and nucleic acid has been achieved by the discovery of 'peptide anticodon' that deciphers stop codons in mRNA (Ito et al. 2000). It is surprising that it took 4 decades since the discovery of the genetic code to figure out the basic mechanisms behind the deciphering of its 64 codons.

• BMB Reports
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• 제52권5호
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• pp.304-311
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• 2019

The cytoplasmic FMR1-interacting protein family (CYFIP1 and CYFIP2) are evolutionarily conserved proteins originally identified as binding partners of the fragile X mental retardation protein (FMRP), a messenger RNA (mRNA)-binding protein whose loss causes the fragile X syndrome. Moreover, CYFIP is a key component of the heteropentameric WAVE regulatory complex (WRC), a critical regulator of neuronal actin dynamics. Therefore, CYFIP may play key roles in regulating both mRNA translation and actin polymerization, which are critically involved in proper neuronal development and function. Nevertheless, compared to CYFIP1, neuronal function and dysfunction of CYFIP2 remain largely unknown, possibly due to the relatively less well established association between CYFIP2 and brain disorders. Despite high amino acid sequence homology between CYFIP1 and CYFIP2, several in vitro and animal model studies have suggested that CYFIP2 has some unique neuronal functions distinct from those of CYFIP1. Furthermore, recent whole-exome sequencing studies identified de novo hot spot variants of CYFIP2 in patients with early infantile epileptic encephalopathy (EIEE), clearly implicating CYFIP2 dysfunction in neurological disorders. In this review, we highlight these recent investigations into the neuronal function and dysfunction of CYFIP2, and also discuss several key questions remaining about this intriguing neuronal protein.

• BMB Reports
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• 제44권8호
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• pp.529-534
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• 2011

Ribosomal protein S3 (rpS3) is a multifunctional protein involved in translation, DNA repair, and apoptosis. The relationship between rpS3 and cyclin-dependent kinases (Cdks) involved in cell cycle regulation is not yet known. Here, we show that rpS3 is phosphorylated by Cdk1 in G2/M phase. Co-immunoprecipitation and GST pull-down assays revealed that Cdk1 interacted with rpS3. An in vitro kinase assay showed that Cdk1 phosphorylated rpS3 protein. Phosphorylation of rpS3 increased in nocodazole-arrested mitotic cells; however, treatment with Cdk1 inhibitor or Cdk1 siRNA significantly attenuated this phosphorylation event. The phosphorylation of a mutant form of rpS3, T221A, was significantly reduced compared with wild-type rpS3. Decreased phosphorylation and nuclear accumulation of T221A was much more pronounced in G2/M phase. These results suggest that the phosphorylation of rpS3 by Cdk1 occurs at Thr221 during G2/M phase and, moreover, that this event is important for nuclear accumulation of rpS3.

• Mycobiology
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• 제43권3호
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• pp.354-359
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• 2015

Blossom blight in strawberry was first observed in a green house in Nonsan, Damyang, and Geochang areas of Korea, between early January to April of 2012. Disease symptoms started as a grey fungus formed on the stigma, which led to the blossom blight and eventually to black rot and necrosis of the entire flower. We isolated the fungi purely from the infected pistils and maintained them on potato dextrose agar (PDA) slants. To test Koch's postulates, we inoculated the fungi and found that all of the isolates caused disease symptoms in the flower of strawberry cultivars (Seolhyang, Maehyang, and Kumhyang). The isolates on PDA had a velvet-like appearance, and their color ranged between olivaceous-brown and smoky-grey to olive and almost black. The intercalary conidia of the isolates were elliptical to limoniform, with sizes ranging from $5.0{\sim}10.5{\times}2.5{\sim}3.0{\mu}m$ to $4.0{\sim}7.5{\times}2.0{\sim}3.0{\mu}m$, respectively. The secondary ramoconidia of these isolates were 0- or 1-septate, with sizes ranging betweem $10.0{\sim}15.0{\times}2.5{\sim}3.7{\mu}m$ and $8.7{\sim}11.2{\times}2.5{\sim}3.2{\mu}m$, respectively. A combined sequence analysis of the internal transcribed spacer regions, partial actin (ACT), and translation elongation factor 1-alpha (TEF) genes revealed that the strawberry isolates belonged to two groups of authentic strains, Cladosporium cladosporioides and C. tenuissimum. Based on these results, we identified the pathogens causing blossom blight in strawberries in Korea as being C. cladosporioides and C. tenuissimum.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.403-411
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• 2005

The relationship between plasmid (~9.5 kb) and pediocin PA-1 in P. acidilactici K10 was confirmed by plasmid curing. The pediocin operon of P. acidilactici K10 was amplified by PCR (polymerase chain reaction), and the nucleotide sequence was analyzed. The sequence of the pediocin operon of P. acidilactici K10 was similar to those of P. acidilactici strains producing pediocin PA-1/ AcH. For the expression of pediocin PA-1 in E. coli, a pQEPED (pQE-30 Xa::mature pedA) was constructed. His-tagged recombinant pediocin PA-1 (-6.5 kDa) was translated by cell-free in vitro transcription and translation using pQEPED as a DNA template. Theresult of slot blotting assay showed that transcription of recombinant pedA in E. coli M15 was induced by the addition of isopropyl-$\beta$-D-thiogalactopyranoside (IPTG) at the final concentration of 1 mM. Although the recombinant pediocin PA-1 inhibited the growth of E. coli, it was expressed in the host strain and purified by nickel-nitrilotriacetic acid (Ni-NTA) metal-affinity chromatography under denaturing condition. This is the first report for the production and one-step purification of biologically active recombinant pediocin PA-1 in E. coli.

• 식물조직배양학회지
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• 제22권1호
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• pp.19-23
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• 1995

당근의 현탁배양 캘러스 세포가 고온에 노출되었을때 다른 식물에서 알려진 것과 유사한 열충격반응을 나타낸다. 이는 기존의 유전자의 발현을 억제하고 새로운 열충격단백질을 생산하기 위한 열충격유전자의 발현을 촉진한다. 이러한 열충격유전자의 고온조건에서의 발현은 주로 전사과정에서 이루어지는 것으로 알려져 있다. 그러나 몇가지의 경우에서 이들 열충격 유전자의 발현이 번역과정에서 조절되는 것으로 보고된 바 있다. 본 고에서는 열충격 과정과는 무관한 토끼의 적혈구로 만들어진 시험관 내 번역시스템과 2차원단백질분리 시스템을 이용하여 생성된 단백질의 양을 통해, 번역에 사용된 mRNA의 양을 추정하였다. 이를 생체내에서 같은 조건에서 만들어진 단백질의 양과 비교할 때에 당근세포내의 특정 mRNA의 양과 해당 열충격단백질의 양이 $ 30^{\circ}C$에서 불일치함을 확인하였다. 이를 통해 당근의 캘러스 세포가 열충격 반응을 나타내는 가장 낮은 온도인 $30^{\circ}C$에서 mRNA의 양과는 다소 무관하게 해당 열충격단백질을 번역을 촉진하는 과정이 있음을 추정할 수 있었다.

• BMB Reports
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• 제54권9호
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• pp.470-475
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• 2021

Low-dose metronomic chemotherapy has been introduced as a less toxic and effective strategy to inhibit tumor angiogenesis, but its anti-angiogenic mechanism on endothelial progenitor cells (EPCs) has not been fully elucidated. Here, we investigated the functional role of regulated in development and DNA damage response 1 (REDD1), an endogenous inhibitor of mTORC1, in low-dose doxorubicin (DOX)-mediated dysregulation of EPC functions. DOX treatment induced REDD1 expression in bone marrow mononuclear cells (BMMNCs) and subsequently reduced mTORC1-dependent translation of endothelial growth factor (VEGF) receptor (Vegfr)-2 mRNA, but not that of the mRNA transcripts for Vegfr-1, epidermal growth factor receptor, and insulin-like growth factor-1 receptor. This selective event was a risk factor for the inhibition of BMMNC differentiation into EPCs and their angiogenic responses to VEGF-A, but was not observed in Redd1-deficient BMMNCs. Low-dose metronomic DOX treatment reduced the mobilization of circulating EPCs in B16 melanoma-bearing wild-type but not Redd1-deficient mice. However, REDD1 overexpression inhibited the differentiation and mobilization of EPCs in both wild-type and Redd1-deficient mice. These data suggest that REDD1 is crucial for metronomic DOX-mediated EPC dysfunction through the translational repression of Vegfr-2 transcript, providing REDD1 as a potential therapeutic target for the inhibition of tumor angiogenesis and tumor progression.

• 대한원격탐사학회지
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• 제37권3호
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• pp.567-575
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• 2021

고해상도 스테레오 위성영상에서 제공되는 초기 RPC의 보정과 이로부터 생성된 DEM 보정을 위해서는 지상기준점 획득이 선행되어야 한다. 기준점 획득은 현장답사와 GPS 측량, 지상기준점에 대응하는 영상좌표 독취 등을 수행해야 하는 매우 번거로운 작업이다. 그리고 접근이 힘들거나 불가능한 지역(갯벌, 극지대, 화산지대 등)에는 기준점 설치와 측정이 힘들기 때문에 이를 대체할 수 있는 방법이 필요하다. 이 연구에서 WorldView-2 위성영상과 초기 RPC로부터 제작된 DEM 보정을 위해 기준점의 지상좌표와 영상좌표 측량을 피하고 기 구축된 지상좌표 패키지만을 활용한 3차원 표면매칭 기법을 제안한다. 국토지리정보원 국토정보플랫폼에서 공공삼각점의 위치정보를 획득하고 제작된 DEM과 3차원 표면매칭을 실시하여 DEM을 보정하였다. 3차원 표면매칭으로 얻은 3축 이동과 회전량의 정확도를 평가하기 위하여 검사점으로 확인한 결과 평면오차는 2 m, 수직오차는 1 m 이내의 결과를 얻을 수 있었다.

• 한국초지조사료학회지
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• 제37권3호
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• pp.231-236
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• 2017

Salt stress is one of the most limiting factors that reduce plant growth, development and yield. However, identification of salt-inducible genes is an initial step for understanding the adaptive response of plants to salt stress. In this study, we used an annealing control primer (ACP) based GeneFishing technique to identify differentially expressed genes (DEGs) in Italian ryegrass seedlings under salt stress. Ten-day-old seedlings were exposed to 100 mM NaCl for 6 h. Using 60 ACPs, a total 8 up-regulated genes were identified and sequenced. We identified several promising genes encoding alpha-glactosidase b, light harvesting chlorophyll a/b binding protein, metallothionein-like protein 3B-like, translation factor SUI, translation initiation factor eIF1, glyceraldehyde-3-phosphate dehydrogenase 2 and elongation factor 1-alpha. These genes were mostly involved in plant development, signaling, ROS detoxification and salt acclimation. However, this study provides new molecular information of several genes to understand the salt stress response. These genes would be useful for the enhancement of salt stress tolerance in plants.