고해상도 전사체 분석법을 통한 신경손상 후 척수 소교세포의 신경병증성 통증 유전자 발현에 관한 연구

학위논문 (박사)-- 서울대학교 대학원 치의학대학원 치의과학과, 2017. 8. 오석배.Microglia are resident immune cells responsible for maintaining homeostasis and sensing neuronal injury in the central nervous system (CNS). Microglial activation in response to peripheral nerve injury is known to be important in inducing pain hypersensitivities. Activated microglia is accompanied by changes in hypertrophic morphology, rate of proliferation, and alterations in gene expression. Large-scale screening to identify pain-related genes on tissue level such as in dorsal root ganglion (DRG) and spinal cord has revealed significantly altered expression of a number of genes. However, most of these genes are neuronal not microglial, indicating that whole tissue analysis may have limitations in finding targets from minor fraction of whole tissue transcriptome. In the present study, I adopted high resolution transcriptome assay from individually collected pools of 10 spinal microglia cells to identify changes in expression levels and cell-to-cell variation of activated microglial genes in peripheral nerve injury model. Differentially expressed genes (DEGs) analysis revealed that miR-29c was a critical factor for microglia activation and the development of neuropathic pain at post-operative day 1 (POD1). According to gene ontology analysis, early POD1 microglia exhibited a very distinct expression profile compared to late POD7 microglia, possibly leading to the transition from initiation to maintenance of neuropathic pain. Genes related to sensing function were influenced at POD1 while expressions of genes induced by signaling pathways were more predominant at POD7. Variation analysis revealed that 56 genes in group C genes showed decreased variance in injury with concomitant increase in variance in sham. In fact, only the group C genes showed tight clustering of the four experimental conditions. The 56 microglial genes, including Gria1, the gene encoding AMPA receptor subunit GluA1, potentially linked to the maintenance of neuropathic pain. Gria1 may regulate TNFα release via changing permeability of the AMPA receptor to Ca2+ influx. This study provides insights into spinal microglial biology and reveals novel microglial targets for the treatment of neuropathic pain.Background 1 1. Microglial activation 1 2. Microglial activation in neuropathic pain 5 3. Gene expression in neuropathic pain 4 Purpose 7 Introduction 8 Materials and Methods 11 Results 33 Discussion 74 Reference 82 국문초록 99Docto

사람 신경교종에서 protein kinase B(PKB)/ Akt 경로를 억제하는 암

Dept. of Medical Science/석사[한글]신경교종은 성인의 중추신경계에서 가장 흔하게 발생하는 종양으로 성인 뇌종양의 40-50%를 차지한다. 악성 신경교종의 환자는 나쁜 예후와 높은 사망률을 나타낸다. Akt 신호경로의 조절은 종양형성에 있어서 매우 중요하다. 이 연구에서는 신경교종에서 Akt 신호 경로를 음성적으로 조절하는 PHLPP 의 역할을 알아보기 위해 30 개의 신경교종과 23 개의 정상 뇌 조직을 이용하여 mRNA 와 단백질의 발현을 real-time PCR 과 웨스턴 블롯팅 방법을 이용해서 분석하고 정상뇌조직과 신경교종의 발현을 비교하였다. 신경교종 환자의 조직에서 PHLPP 의 mRNA 와 단백질 모두의 발현정도는 정상 뇌조직에서 보다 상당히 낮았다. PTEN 의 발현도 정상조직과 비교할 때 신경교종에서 더 낮게 발현되었다. 이와 반대로, 인산화된 Akt 는 23 개의 정상조직 중에서 21 개에서 발현되지않은 반면 신경교종의 대부분에서 발현이 나타났다. 따라서 우리는 PHLPP 는 암억제 유전자이며 신경교종에서 PHLPP 와 pAkt 가 역관계에 있음을 밝혔다. 이러한 연구결과는 PHLPP 와 PTEN 이 Akt 신호경로를 음성적으로 조절하며 앞으로 PHLPP 가 신경교종의 유전자 치료 또는 새로운 화학요법에서 중요한 타깃이 될 수 있을 것이라는 사실을 제시한다.prohibitio

Multi-channel Multi-rate based QoS Routing Algorithm over Mobile Ad Hoc Networks

Master본 논문에서는 이동 애드 혹 네트워크 상에서 멀티미디어 전송을 위해 요청된 대역폭을 보장하는 다중 채널 다중 전송률 기반의 QoS 라우팅 알고리즘을 제안한다. 우선 주기적인 채널 모니터링을 기반으로 대역폭을 예측한다. 제안한 라우팅 알고리즘은 가용 대역폭의 최대화와 대역폭 제약조건을 만족하면서 이용할 수 있는 채널의 수의 최대값을 가지는 경로를 찾는다. IEEE 802.11 환경을 기반으로 하여 다중 채널과 다중 전송률을 지원한다. 마지막으로, 실험 결과를 통해 제안하는 전송 기법의 성능을 검증한다

Development of Pre-breeding Materials in Capsicum spp. and Map-based Cloning of a Male Sterile Gene, ms1035 in Tomato

학위논문 (박사)-- 서울대학교 대학원 : 식물생산과학부(원예과학전공), 2014. 2. 강병철.Tomato and pepper belong to the Solanaceae family and economically important vegetable crops worldwide. The main objectives of tomato and pepper breeding are developing high yield, pest resistant, and quality cultivars. Narrowed genetic diversity in commercial lines due to under-utilization of germlasm is a serious problem in tomato and pepper breeding. Therefore, discovering of allelic diversity and characterization of useful traits are essential for breeding. In the first chapter, species identification markers for Capsicum spp. were developed. Identification of Capsicum species has always been controversial because of ambiguous morphological behaviors. Moreover, most previous studies for species identification using molecular markers also had disadvantages that were low reproducibility and unsuitability for handling large quantities of samples. Here, SNP markers derivd from conserved ortholog set II (COS II) and the Waxy gene were developed as candidate maker set for species identification. Furthermore, phylogenetic analysis supported that C. annuum, C. baccatum, and C. pubescens clades were clearly separated. Closely related species C. chinense and C. frutescens were divided into subclades, indicating that the two species are apparently different. C. chacoense, the most controversial species, was belonged to C. baccatum clade. These results provide the information of genetic relationship of Capsicum species and reliable species classification method. In the second chapter, allele mining was performed to find useful allelic variation of a virus resistance gene in natural germplasm pool and ethyl methanesulfonate (EMS) mutagenized population to enhance the genetic diversity of Capsicum species. A fast and accurate method was developed to mine the useful alleles in significant number of germplasm using high resolution melting (HRM) analysis. Of 248 pepper germplasm, 13 newly obtained allelic variations of eIF4E were identified and one accession of them, C03946 (pvrHRM113) from C. baccatum was shown to carry strong resistance to TEV-HAT virus. Furthremore, five more allelic variations from EMS-mutageneized M1 population were also identified. Therefore, this result provides the strength of genetic diversity in Capsicum spp. and a useful tool for mining novel alleles. In the third chapter, a male sterile gene of tomato was characterized. Male sterility is the one of the most important characteristics for plant breeding. Here, the map-based cloning of the ms1035 mutant of tomato was performed and a responsible gene encoding a bHLH transcription factor was discovered. With morphological defects and molecular evidence, Ms1035 played a pivotal role for pollen development after meiotic stage. ms1035 was firstly isolated gene in tomato discovered by map-based cloning among the pollen development related genes at early stage. This provides that the insight of molecular evidence for tomato pollen development and utilization of male sterility line to improve tomato breeding.Contents Abstract i Contents iv List of tables ix List of figures xi List of abbreviations xiii General introduction 1 Literature review 6 Chapter I Identification of Capsicum Species Using SNP Markers Based on High-Resolution Melting Analysis Abstract 61 Introduction 63 Materials and methods Plant materials 67 Morphological trait observation 67 Genomic DNA extraction 67 Marker screening 70 HRM analysis conditions 70 DNA sequence analysis 71 Dendrogram tree and genetic distance analysis 71 Results Species identification based on morphology 72 Development of species identification markers using nuclear DNA sequences 74 Phylogenetic analysis of Capsicum species 77 Discussion 83 References 88 Chapter II A Survey of Natural and EMS-induced Variations of eIF4E Using High-Resolution Melting Analysis in Capsicum Species Abstract 94 Introduction 96 Materials and methods Plant materials 99 Chemical mutagenesis 99 DNA extraction 101 HRM analysis 101 Sequencing and sequence alignment of eIF4E fragment 102 Virus inoculation and disease resistant evaluation 103 Results Screening of pvrHRM variation in Capsicum germplasm using HRM 104 Nucleotide and amino acid changes in natural variants 105 Virus resistance test on new allelic variants 108 Generation of an EMS mutant population 111 Application of HRM to mutation screening 116 Discussion 119 References 124 Chapter III Tomato Male Sterile Gene, ms1035 Regulates Tapetum Degeneration and Meiosis Abstract 131 Introduction 133 Materials and methods Plant materials 137 Phenotypic observation and genetic analysis of ms1035 137 Scanning electron microscopic (SEM) analysis 138 Light microscopic analysis and transmission electron microscopic (TEM) observation 138 DAPI staining analysis for meiotic process 139 DNA extraction 140 Alignment of BAC clone and marker development using high-resolution melting (HRM) analysis 140 Fine mapping of ms1035 141 Total RNA isolation and RT-PCR 142 5’ RACE analysis for transcription start site survey 142 Phylogenetic analysis 145 Complementation of the dyt1 mutant 145 Localization of expressed Ms1035 by in situ hybridization 146 RNA transcriptome analysis by RNAseq 147 Results ms1035 shows complete sterility with no ability to produce viable pollen 149 Pollen development of ms1035 is arrested at tetrad stages 149 Defe cts in degeneration of tapetal cells result in failure of pollen development in ms1035 154 Meiosis of ms1035 is arrested at anaphase I 158 ms1035 encodes a bHLH transcription factor 160 Localization of the Ms1035 gene by RNA in situ hybridization 166 Complementation of male sterility with a full length Ms1035 gene 169 Comparison of global gene expression between male sterilie and fertile plants by RNAseq analysis 173 Discussion 186 References 193 Abstract in Korean 203Docto

Fitting GARCH-GPD Model for VaR Estimation of KOSPI

MasterKOSPI data의 return value of loss를 2007/11/01 부터 2009/10/31 까지 VaR의 measure를 이용해서 예측하였다. VaR을 좀더 정확하게 예측하기 위해서 loss distribution function을 normal base가 아닌 GPD base로 선택하였다. 이 선택에 대한 근거는 앞의 Extreme Value Theory이다. GPD의 parameter를 fitting 하기 위해서 maximum likelihood estimator 기법을 사용하고, 현재 market에서 실질적으로 보여지고 있는 Volatility clustering의 현상을 model에 더하여 fitting의 정도를 높이기 위해 GARCH model을 이용한 volatility prediction을 하였다. 이러한 복합적인 모델이 normal distribution assumption 이나 no-GARCH fitting model을 사용했을 때 보다 더욱 잘 fitting 된 다는 것을 violation의 갯수와 Back-Testing으로 나타내었다.We examine the suitability of the GARCH-GPD model in predicting extreme financial losses. The GARCH-GPD model is a two-stage model consisting of the GARCH model to deal with stochastic volatility in financial time series and the GPD model to handle heavy tails in financial losses. This model is fitted to KOSPI data from 2005/10/31 to 2009/10/31 to obtain a series of one-day VaR's. We observe that these one-day VaR's based on the GARCH-GPD model perform better than those obtained by other models such as unconditional approaches and conditional normal model

이동 애드 혹 네크워크 상에서 경로 지연과 데이터 전송률을 고려한 멀티레이트 기반의 효율적인 전송 알고리즘

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Graphene Oxide as Multi-Functional p-Dopant of Flexible, Transparent Single-Walled Carbon Nanotube Electrodes for Flexible

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