• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2000년도 잠사과학 100주년 국제심포지엄 및 추계학술대회
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• pp.62-62
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• 2000

No Abstract.See Full-text

• Molecules and Cells
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• 제25권2호
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• pp.258-264
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• 2008

Deschampsia antarctica is the only monocot that thrives in the tough conditions of the Antarctic region. It is an invaluable resource for the identification of genes associated with tolerance to various environmental pressures. In order to identify genes that are differentially regulated between greenhouse-grown and Antarctic field-grown plants, we initiated a detailed gene expression analysis. Antarctic plants were collected and greenhouse plants served as controls. Two different cDNA libraries were constructed with these plants. A total of 2,112 cDNA clones was sequenced and grouped into 1,199 unigene clusters consisting of 243 consensus and 956 singleton sequences. Using similarity searches against several public databases, we constructed a functional classification of the ESTs into categories such as genes related to responses to stimuli, as well as photosynthesis and metabolism. Real-time PCR analysis of various stress responsive genes revealed different patterns of regulation in the different environments, suggesting that these genes are involved in responses to specific environmental factors.

• Journal of Microbiology and Biotechnology
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• 제17권8호
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• pp.1330-1337
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• 2007

To better understand the gene expression of the cold-adapted polar diatom, we conducted a survey of the Chaetoceros neogracile transcriptome by cDNA sequencing and expression of interested cDNAs from the Antarctic diatom. A non-normalized cDNA library was constructed from the C. neogracile, and a total of 2,500 cDNAs were sequenced to generate 1,881 high-quality expressed sequence tags (ESTs) (accession numbers EL620615-EL622495). Based on their clustering, we identified 154 unique clusters comprising 342 ESTs. The remaining 1,540 ESTs did not cluster. The number of unique genes identified in the data set is thus estimated to be 1,694. Taking advantage of various tools and databases, putative functions were assigned to 939 (55.4%) of these genes. Of the remaining 540 (31.9%) unknown sequences, 215 (12.7%) appeared to be C. neogracile-specific since they lacked any significant sequence similarity to any sequence available in the public databases. C. neogracile consisted of a relatively high percentage of genes involved in metabolism, genetic information processing, cellular processes, defense or stress resistance, photosynthesis, structure, and signal transduction. From the ESTs, the expression of these putative C. neogracile genes was investigated: fucoxanthin chlorophyll (chl) a,c-binding protein (FCP), ascorbate peroxidase (ASP), and heat-shock protein 90 (HSP90). The abundance of ASP and HSP90 changed substantially in response to different culture conditions, indicating the possible regulation of these genes in C. neogracile.

• 한국작물학회지
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• 제55권2호
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• pp.151-158
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• 2010

지금까지 양구슬냉이의 유전정보는 거의 연구되지 않았으므로 우리는 양구슬냉이의 잎으로부터 cDNA library를 제작하고 발현유전자의 종류와 기능별 분류를 조사하였다. 그 결과를 요약하면 다음과 같다. 1. cDNA library에서 1334개 의 클론들을 얻었고 삽입된 단편들의 염기서열의 평균길이는 736bp였다. 우리는 1269개의 high-quality expressed sequence tags (ESTs) 서열을 얻었다. 이러한 EST의 클러스터 분석결과 고유 염기서열(unigene)을 가진 유전자의 수는 851개를 나타냈다. 2. Unigene 476개는 GeneBank에 기능이 알려진 유전자들과 고도의 상동성을 나타내었다. 다른 375개의 unigene들은 기능이 알려지지 않은 것들이었다. 나머지 63개는 NCBI데이터베이스에 어떤 유전자와도 상동성을 보이지 않았고 이러한 유전자들은 아마도 양구슬냉이의 잎에서 발현되는 새로운 유전자일 것으로 보인다. 3. 데이터베이스에서 상동성을 나타낸 EST들을 기능별 주석에 따라서 17개의 카테고리로 분류하였다. 대표적으로 가장 분포도가 높은 카테고리는 결합 기능 또는 보조인자 요구의 단백질(27%), 대사(11%), 세포 소기관 위치(11%), 세포수송과 수송기관 그리고 수송 경로(7%), 에너지(6%), 대사와 단백질 기능의 조절(6%) 등이 있다. 이러한 우리의 연구 결과는 양구슬냉이의 유용한 유전적 자원과 전반적인 mRNA 발현 정보를 제공해 줌으로써 대체 에너지 작물로 떠오르는 양구슬냉이의 다양한 분자적 연구에 기여할 것으로 사료된다.

• Journal of Plant Biotechnology
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• 제36권3호
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• pp.281-288
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• 2009

Seed germination is the important stage to express many genes for regulation of energy metabolism, starch degradation and cell division from seed dormancy state. For the functional analysis of seed germination mechanisms, we were analyzed the rice cDNA clones (Oryzasativa cultivar Ilpum) obtained from seed imbibition during 48 hours. Total number of 18,101 Expressed Sequence Tags (ESTs) were clustered using SeqMan program. Among them, 8,836 clones were identified as unique clones. We identified the chitinase gene specifically expressed in seed germination and amylase gene involved to starch degradation from the full length cDNA analysis, and several genes were registered to NCBI GeneBank. To analyzed the commonly expressed genes between inmature seed and germinated seed, 25,66 inmature ESTs and 18,101 germinated ESTs were clustered using SeqMan program and identified 2,514 clones as commonly expressed unigene. Among them, alpha-glubulin and alcohol dehydrogenase I were supposed to LEA genes only expressed in the immature and germinated seed stages. For the clustering of orthologous group genes, we further analyzed the 8,836 EST clones from germinating seeds using NCBI clusters of orthologous groups database. Among the clones, 5,076 clones were categorized into information storage and processing, cellular processes and signaling, metabolism and poorly characterized genes, proportioning 783 (14.29%), 1,484 (27%), 1,363 (24.8%) and 1,869 (34%) clones to the previous four categories, respectively.

• 한국패류학회지
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• 제29권3호
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• pp.181-187
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• 2013

In order to investigate environmental stress inducible genes in abalone, we analyzed differentially expressed transcripts from a Pacific abalone, Haliotis discus hannai, after exposure to heat-, cold- or hyposalinity-shock by suppression subtractive hybridization (SSH) method. 1,074 unique sequences from SSH libraries were composed to 115 clusters and 986 singletons, the overall redundancy of the library was 16.3%. From the BLAST search, of the 1,316 ESTs, 998 ESTs (75.8%) were identified as known genes, but 318 clones (24.2%) did not match to any previously described genes. From the comparison results of ESTs pattern of three SSH cDNA libraries, the most abundant EST was different in each SSH library: small heat shock protein p26 (sHSP26) in heat-shock, trypsinogen 2 in cold-shock, and actin in hyposalinity SSH cDNA library. Based on sequence similarities, several response-to-stress genes such as heat shock proteins (HSPs) were identified commonly from the abalone SSH libraries. HSP70 gene was induced by environmental stress regardless of temperature-shock or salinity-stress, while the increase of sHSP26 mRNA expression was not detected in cold-shock but in heat-shock condition. These results suggest that the suppression subtractive hybridization method is an efficient way to isolate differentially expressed gene from the invertebrate environmental stress-response transcriptome.

• 한국수산과학회지
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• 제36권5호
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• pp.442-448
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• 2003

Melanin concentrating hormone (MCH) regulating color change of fish skin was identified from brain cDNA library of Olive flounder (Paralichthys olivaceus) during the analysis of Expressed Sequence Tags (ESTs). Olive flounder MCH gene consisted of 598 nucleotides encoding 150 amino acids. Olive flounder MCH protein revealed to contain signal peptide of 19 amino acid residues, pro-MCH of 131 amino acids being processed to biologically active and mature form of hormone with 25 amino acid residues at the carboxyl terminus. A comparative structural analysis revealed that Olive flounder MCH precursor had low sequence identity with other fish species and mammalian counterparts, while the amino acid sequences of mature hormone had a relatively high identity and more conserved. RT-PCR analysis revealed that olive flounder MCH precersor gene was expressed spectically only in the brain and not in other tissues.

• Bioinformatics and Biosystems
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• 제1권2호
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• pp.99-102
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• 2006

BLAST(Basic Local Alignment Search Tool)는 서열 데이터베이스 탐색을 위하여 가장 많이 사용되는 프로그램이다. 전체 서열간의 최적 글로벌 정렬을 수행하는 대신에 지역적 유사성이 있는 부분을 찾아 서열 짝짓기를 수행하는 특징을 갖는다. 일반적인 연구자들은 서열 상동성 검색을 위해 NCBI에 접속하여 웹 브라우저를 통해 온라인으로 BLAST를 수행하게 되는데, 이 경우 사용자 각각의 네트워크 환경이나 입력할 데이터양에 따른 검색속도의 지연 및 제한 등과 같은 여러 문제에 부딪히게 되고, 또한 보안유지가 필요한 서열 데이터의 유출 가능성이 존재한다. 그러므로 대량의 서열 데이터에 대하여 빠르고 안전하게 BLAST 상동성 검색이 가능한 Local BLAST 검색 시스템의 필요성이 증대되고 있다. 본 연구에서는 NCBI의 Genbank에서 공개된 동물의 발현 유전자 단편들(ESTs)에 대한 데이터를 이용하여 소, 돼지, 닭, 등의 경제형질과 연관된 유용 유전자만을 추출하여 이들만으로 구성된 새로운 데이터베이스를 구축하였고, 또한 이들을 사용할 수 있는 새로운 검색시스템을 개발하였다 자체 제작한 Perl script를 사용하여 필요한 데이터를 축종별로 추출 하여 새로운 DB를 구축하였으며 이 속에는 소의 경우 650,046개, 돼지의 경우 368,120개, 닭의 경우 693,005개의 발현 유전자 단편들(ESTs)이 포함된다. 또한 이들 DB 분석이 가능한 Local Animal BLAST Web 검색시스템(http://bioinfo.kohost.net)을 고성능 병렬 PC Cluster 시스템과 연동하도록 자체 구축함으로써 본 시스템이 보다 효율적인 생물정보학 연구수행이 기여할 것으로 기대된다.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2003년도 제46회 춘계 학술연구 발표회
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• pp.52-52
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• 2003

Expressed sequence tags(ESTs) constitute a rapid and informative strategy for studying gene-expression profiles of specific stages and tissues. In this report, a cDNA library constructed from late larval Hydropsyche sp. was used to generate ESTs. Caddis larval silk-gland produce silk which are used in constructing their retreats and cases in the aquatic situation. (omitted)

• 한국발생생물학회지:발생과생식
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• 제19권4호
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• pp.227-234
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• 2015

The objective of this study was to investigate the expression of bovine luteum expressed sequence tags (ESTs), vascular endothelial growth factor (VEGF), and tumor necrosis factor receptor 1 (TNFR1) and the presence of functional ESTs in the bovine corpus luteum (CL) during different stages of the estrus cycle. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed a difference in the expression of ESTs during the CL stage. Concentration of ESTs in the CL tissue increased significantly from the mid-luteal stage and decreased thereafter. RT-PCR analysis showed higher levels of the EST genes in the CL of the mid-luteal stage than in other stages, and the same level of expression of VEGF. Immunohistochemistry analysis of the tissue from CL formation to regression showed low cytosol and aggregation of the nucleus. And activity caspase 3 (apoptosis detector) was most strongly detected in the CL1 stage of bovine. During the estrous cycle, the cytosol was magnified and differentiation of the nucleus was clearly manifested. The ESTs affected the CL, and the relationship between VEGF and TNFR1 played a pivotal role for CL development and activation, dependent on the stage of CL. These results suggest local production of ESTs, the presence of functional ESTs in the bovine CL, and that ESTs play a role in regulating the function of cell death in bovine CL.