CuxS를 導入한 Acrylonitrile-Acrylamide 共重合體의 電氣的 性質

여창열,김동철,송해영 忠南大學校 産業技術硏究所 1989 산업기술연구논문집 Vol.4 No.2

To improve the electrical conductivity of acrylonitrile film, acrylonitrile copolymer was synthesiz ed conductive polymer, which was acrylonitrile-acrylamide complex induced by CuxS The conclusion obtained from this study are as follows ; 1. The conductivity of CuxS-AN-AA film was much influenced by pH, conentrations of CuSO₄, (NH₃OH)₂SO₄, Na₂S₂O₃and reaction time. 2. The volume and Surface resistivities of CuxS-AN-AA film were increased by order of 10(Ω㎝) in volume resistivities, 10(Ω) in surface resistivities than those of AN-AA copolymer. 3. The Tm value of CuxS-induced copolymer was lower than that of AN-AA copolymer in DSC Curve, 4. CuxS-AN-AA copolymer complex was decreased in tensile properties

한국산 풀색먼지벌레족

여창열 慶北大學校 基礎科學硏究所 1993 慶北大學敎 基礎科學硏究所 硏究論文集 Vol.14 No.-

韓國産 풀색먼지벌레族(딱정벌레科, 초시목)의 系統分類 : Coleoptera, Carabidae

余彰悅,李昌彦 韓國自然史博物學會 1993 生物과 自然 Vol.23 No.2

Spermathecae and hind wing venations of thirteen species under tribe Callistini from Korea were observed. Cluster analysis and principal component analysis for eleven species were performed in order to study phylogentic relationships, two species were excluded because of missing data. For the numerical analysis, eighteen quantitative characters and eighteen qualitative characters were used, most of them are used as keys for classifying genera, subgenera including morphology of genitalia. Spermathecae of thirteen species were illustrated in figure. Haplochlaenius costiger and Chlaenius circumdatus which bearing well developed copulatory piece had very simple spermatheca, spermathecal duct and spermathecal gland were not divided as a independent organ. The spermatheca of Ch. virgulifer, whose endophallus have chitinized but copulatory piece not present, was constituted with short and not curved spermathecal duct, rudimentary spermathecal reservoir and spermathecal gland which connected to spermathecal duct by its gland duct. The other species which bearing most simple form of aedeagus (no copulatory piece and not chitinized endophallus) had rather diversified spermatheca that compsed of curved or turned spermathecal duct, well developed (enlarged or elongated) spermathecal reservoir, spermathecal gland and obvious spermathecal appendix. In those species under subgenus Chlaeniellus, spermathecal gland was opened at spermathecal appendix, characteristically. General feathers of wing venation are enlarged third radial cell with considerably reduced anterior sector cell and presence of posterior sector. Callistomimus modestus distinguished by absence of wedge cell. Relative wing size ranged from 3.5 to 2.3 except Ch. naeviger whose mean value was about 1.4. In the case of Ch. naeviger, there occured brachyptery. According to cluster analysis, Ch. variicornis and Ch. pallipes were closely related and subgenus Spilochlaenius, Ilaenchus and Pachydinodes combined gradually with former group. but subgenus Chlaeniellus and Chlaeniostenus dispersed, respectively. similiar result were obtained from principal component analysis. One species, Chlaenius prostenus, is newly added to Korean fauna, and then 24 species, 10 subgenera, 5 genera under tribe Callistini have been recorded from Korea.

Xenopus laevis rDNA Replication Initiates in the Intergenic Spacer

여창열 한국유전학회 2004 Genes & Genomics Vol.26 No.4

Initiation of DNA replication in metazoan, in general, occurs within specific initiation zones. The metazoan rRNA genes (rDNAs) are arranged in tandem repeated units and replication of the rDNA initiates within the intergenic spacer (IGS) in adult tissues and late stage embryos. However, in embryos undergoing rapid cell division and in extracts from these embryos, rDNA replication has been reported to initiate at multiple, random sites throughout the rDNA. We performed time course analyses of initiation of Xenopus laevis rDNA replication in Xenopus egg extracts by two-dimensional (2D) agarose gel electrophoresis. We found that the first initiation events in rDNA occur preferentially in the intergenic spacer and that, later on, initiation events can occur at multiple sites throughout the rDNA.

Xenopus Protein O-Fucosyltransferase 1 (XPOFUT1) Is Important for Axial Patterning

여창열 한국유전학회 2006 Genes & Genomics Vol.28 No.2

Protein O-fucosyltransferase 1 (POFUT1) catalyzes the addition of O-fucose to a number of cell surface and secreted proteins containing EGF-like repeats. Drosophila and mouse POFUT1 play crucial roles for modulating notch signaling, and mouse embryos lacking POFUT1 show severe defects in somitogenesis, vasculogenesis, cardiogenesis and neurogenesis. We isolated a cDNA encoding putative protein O-fucosyltransferase from Xenopus laevis and named this cDNA as XPOFUT1 based on the sequence homology and functional conservation with human POFUT1. XPOFUT1 is expressed maternally and zygotically. During gastrula stages, it is expressed around the blastopore lip. During tailbud and tadpole stages, the expression of XPOFUT1 is restricted to the brain, eye, branchial arches, pronephros and somites. In order to study the roles of XPOFUT1, we designed a morpholino antisense oligonucleotide (MO) against XPOFUT1. Injection of XPOFUT1 MO caused anterior and posterior truncation of body axis. Our results suggest that XPOFUT1 plays important roles in axial patterning during Xenopus development.

The Expression of VegT Requires Both Xenopus Nodal-Related and FGF Signaling Pathways during Early Xenopus Embryogenesis

김연진,여창열 한국유전학회 2006 Genes & Genomics Vol.28 No.2

Xenopus nodal-related (Xnr) proteins and FGF play crucial roles during mesoderm induction in amphibian Xenopus laevis embryos. The endogenous and ectopic Xnr-induced expression of mesodermal genes, including VegT, requires FGF signaling such that their expression is abolished when FGF signaling is inhibited. However, the molecular mechanism for the interaction between the two signaling pathways is largely unknown. In order to understand their interaction, we isolated a 2.2 kb-long DNA fragment immediately upstream of Xenopus laevis VegT transcription start site and identified a 274 bp-long fragment that requires both Xnr and FGF signaling for transcriptional activation. From this sequence we identified two regulatory elements; one was necessary for Xnr1-induced activation and the other for FGF-induced activation. Our results suggest that the expression of VegT is regulated, at least in part, by two distinct transcription factors which mediate Xnr and FGF signaling, respectively.

CuxS를 도입한 Acrylonitrile-Sodium-p-Styrenesulfonate 공중합체의 전기적 성질

김동철,송해영,여창열,Kim, Dong-Cheol,Song, Hae-Yeong,Yeo, Chang-Yeol 한국섬유공학회 1990 한국섬유공학회지 Vol.27 No.3

To improve the electrical conductivity of acrylonitrile film, acrylonitrile copolymer was synthesized conductive polymer, which was acrylonitrile-sodium-p-styrene sulfonate complex induced by CuxS. The conclusion obtained from this study are as follows: 1. CuxS-AN-SS film was much influenced by pH, concentrations of CuSO4, (NH3OH)2 SO4, Na2S2O3 and reaction time. 2. The volume and surface resistivities of CuxS-AN-SS was increased by order of 106(cm) in volume resistivities, 107(cm) in surface resistivities than that of AN-SS. 3. The Tm value of CuxS-induces copolymer was lower than that of AN-SS copolymer. 4. The tensile properties of CuxS-AN-SS were generally decreased, and particulary the tensile strength of CuxS-AN-SS was decreased about 45% as compare with that of AN-SS.

구리 이온을 도입한 PAN과 A-PAN의 도전성에 관한 연구

백중현,송해영,손원근,여창열 忠南大學校 産業技術硏究所 1990 산업기술연구논문집 Vol.5 No.2

The PAN-Cu(Ⅱ) and A-PAN-Cu(Ⅱ) complexes were the most stable in the pH 11. The morphology of CuxS-induced PAN, A-PAN had changed into compact form. The Cu(Ⅱ) complex exhibited surface resistivity around 10Ω㎝ when modified iodine in acetone. The resistivity was significantly affected by the amounts of added cupric chloride, iodine and results were satisfactorily obtained by adding more than 20wt% of cupric chloride and about 3wt% iodine. The optimum conduction for the introducing of CuxS was at the CuSO₄concentration of 30g/ℓand the reaction time of 3hrs. The electrical conductivity of CuxS-induced PAN and A-PAN was higher by order of 10-⁴than of the Cu(Ⅱ)complex.

PKA-Mediated Stabilization of FoxH1 Negatively Regulates ERα Activity

Jinah Yum,Hyung Min Jeong,Seulki Kim,Jin Won Seo,Younho Han,Kwang-Youl Lee,여창열 한국분자세포생물학회 2009 Molecules and cells Vol.28 No.1

Estrogen receptor α (ERα) mediates the mitogenic effects of estrogen. ERα signaling regulates the normal growth and differentiation of mammary tissue, but uncontrolled ERα activation increases the risk to breast cancer. Estrogen binding induces ligand-dependent ERα activation, thereby facilitating ERα dimerization, promoter binding and coactivator recruitment. ERα can also be activated in a ligand-independent manner by many signaling pathways, including protein kinase A (PKA) signaling. However, in several ERα-positive breast cancer cells, PKA inhibits estrogen-dependent cell growth. FoxH1 represses the transcriptional activities of estrogen receptors and androgen receptors (AR). Interestingly, FoxH1 has been found to inhibit the PKA-induced and ligand-induced activation of AR. In the present study, we examined the effects of PKA activation on the ability of FoxH1 to represses ERα transcriptional activity. We found that PKA increases the protein stability of FoxH1, and that FoxH1 inhibits PKAinduced and estradiol-induced activation of an estrogen response element (ERE). Furthermore, in MCF7 cells, cçñeN knockdown increased the PKA-induced and estradiol- induced activation of the ERE. These results suggest that PKA can negatively regulate ERα, at least in part, through FoxH1.