미생물 유전체의 in silico분석에 의한 보존적 유전자 탐색

강호영,신창진,강병철,박준형,신동훈,최정현,조환규,차재호,이동근 한국생명과학회 2002 생명과학회지 Vol.12 No.5

미생물 유전체(genome)들 사이의 보존된 유전자 (con-served gene)를 밝히는 것은 생명의 본질을 이해하는데 있어 다양한 의미를 갖는다고 할 수 있을 것이다. 본 연구에서는 보존적 유전자를 찾아내고, distance value를 이용하여 구한 보존성의 정도 C(conservation score)를 이용하여 종간의 유전자 변이의 정도를 단백질 관점에서 분석하였다. 분석에 사용된 자료는 COGs 데이티베이스의 총 43종의 미생물 유전체들이며, 이들은 총 n,009개의 유전자들을 포함하는 3,852 개의 ortholog들로 구성되어있었다. 분석 결과 43종의 미생물 유전체에 대하여 총 $\ulcorner$2개의 유전자들이 보존적인 것으로 나타났으며, 이들 중 72.2%인 52종의 유전자가 단백질 합성에 관련되는 것으로 나타났다. 이들 보존적 유전자들에 대하여 보존성의 정도 C를 계산하여 보존성의 순위를 얻었으며, 가장 잘 보존된 유전자는 CTPase-trans-lation elogation factor (COG0050)로 나타났다. 그리고 72개의 보존적 유전자가 나타내는 CU 모두를 이용한 분석결과 고세균(archaea)과 진정세균(bacteria)이 각각 독자적인 그룹을 형성하는 것을 관찰하였다. 본 연구의 결과에서 도출한 72개의 보존적 유전자는 생명체의 본질적 기능에 중요한 역할을 담당하는 것으로 사료되었고, 생명체의 진화 과정에서 이 유전자들이 보존된 이유와 기능적 연계에 대한 생물학적 연구에 기초 자료를 제공할 것으로 판단되어 진다. Conserved genes are importantly used to understand the major function in survival and replication of living organism. This study was focused on identification of conserved genes in microbial species and measuring the degree of conservation. For this purpose, in silico analysis was performed to search conserved genes based on the conservation level within microbial species. The ortholog list of COGs (Clusters of Orthologous Groups of proteins) in NCBI was used and whole genomes of 43 microbial species were included in that list. The distance value, derived from CLUSTALW multiple alignment program, was used as a descriptor of the conservation level of orthologs. It was revealed that 43 microbial genomes hold 72 conserved orthologs in common. The majority(72.2%) of the conserved genes was related to "translation, ribosomal structure and biogenesis" functional category. A GTPase-translation elogation factor(COG0050) was the best conserved gene from the distance value analysis. The 72 conserved genes, found in this research, would be useful not only to study minimal function genes but also new drug target among pathogens and to make a model of the virtual cell.tual cell.

Genomic Analysis of miR-21-3p and Expression Pattern with Target Gene in Olive Flounder

Jo, Ara,Lee, Hee-Eun,Kim, Heui-Soo Korea Genome Organization 2017 Genomics & informatics Vol.15 No.3

MicroRNAs (miRNAs) act as regulators of gene expression by binding to the 3' untranslated region (UTR) of target genes. They perform important biological functions in the various species. Among many miRNAs, miR-21-3p is known to serve vital functions in development and apoptosis in olive flounder. Using genomic and bioinformatic tools, evolutionary conservation of miR-21-3p was examined in various species, and expression pattern was analyzed in olive flounder. Conserved sequences (5'-CAGUCG-3') in numerous species were detected through the stem-loop structure of miR-21-3p. Thus, we analyzed target genes of miR-21-3p. Among them, 3' UTR region of PPIL2 gene indicated the highest binding affinity with miR-21-3p based on the minimum free energy value. The PPIL2 gene showed high expression levels in testis tissue of the olive flounder, whereas miR-21-3p showed rather ubiquitous expression patterns except in testis tissue, indicating that miR-21-3p seems to control the PPIL2 gene expression in a complementary repression manner in various tissues of olive flounder. Taken together, this current study contributes to infer the target gene candidates for the miR-21-3p using bioinformatics tools. Furthermore, our data offers important information on the relationship between miR-21-3p and target gene for further functional study.

미생물의 보존적 유전자 탐색

이동근,이재화,이상현,하배진,심두희,박은정,김진욱,이화월,남천석,김남영,이어진,백진욱,하종명,Lee Dong-Geun,Lee Jae-Hwa,Lee Sang-Hyeon,Ha Bae-Jin,Shim Doo-Hee,Park Eun-Kyung,Kim Jin-Wook,Li Hua-Yue,Nam Chun-Suk,Kim Nam Young,Lee Eo-Jin,Back J 한국생명과학회 2005 생명과학회지 Vol.15 No.2

생명체의 본질적 기능에 중요한 역할을 담당하는 유전자들을 밝히기 위해 미생물 유전체들 사이의 공통적 유전자를 밝히는 COG알고리듬을 이용하였다. 진핵생물 3종을 포함한 66종의 미생물에서 63개의 유전자가 보존적이었으며, 단백질 합성에 관여하는 유전자들이 총 52개로 생명현상에서의 단백질의 중요성을 알 수 있었다. 각 보존적 유전자들의 distance value를 이용하여 종간의 유전자 변이의 정도를 보면, ribosomal protein S12 (COG0048)와 ribosomal protein L14 (COG0093)의 보존성이 가장 높았다. 보존적 유전자들의 평균과 분산으로 유전체 분석을 수행한 결과, 고세균과 진정세균의 각 그룹 등 근연종들이 독자적 그룹을 형성하였다. 하지만 각 그룹내의 속 및 유전체의 수와 유전체 변이의 정도는 비례하지 않는 것을 알 수 있었다. To figure out conserved genes in 66 microbial species and measuring the degree of conservation, analyses based on COG (Clusters of Orthologous Groups of proteins) algorithm were applied. Sixty-six microbial genomes, including three eukaryotes, hold 63 conserved orthologs in common. The majority $(82.5\%)$ of the conserved genes was related to translation, meaning the importance of protein in living creatures. Ribosomal protein S12 (COG0048) and L14 (COG0093) were more conserved genes than others from the distance value analysis. Phylogenetically related microbes grouped in genome analysis by average and standard deviation of 63 conserved genes. The 63 conserved genes, found in this research, would be useful in basic research and applied ones such as antibiotic development.

원핵생물과 공통인 진핵생물의 보존적 유전자 탐색

이동근 한국생명과학회 2013 생명과학회지 Vol.24 No.4

생물들에서 생명의 본질적 기능을 수행하는 단백질들의 종류와 보존성을 밝히기 위해 COG (Clusters of Orthologous Groups of proteins) 알고리즘을 이용하였다. 66종의 미생물에서 보존적인 63개의 ortholog 그룹들은 진핵생물 7종에서 104개의 ortholog들로 확산되었으며, 7종 모두의 핵에 보존적인 KOG (euKaryotic Orthologous Group)은 71개였다. 71개 중 단백질 합성에 관여하는 유전자들이 총 54개로 생명현상에서의 단백질의 중요성을 확인할 수 있었다. Distance value로 보존적 유전자가 생물종 사이에 나타내는 유전자 변이의 정도를 파악하니 ‘Translation initiation factor’인 KOG3403과 KOG3271 그리고 ‘Prolyl-tRNA synthetase’ (KOG4163) 등이 높은 보존성을 보였다. 보존적 KOG들의 평균과 분산으로 유전체 분석을 수행하여 꼬마선충이 KOG 평균사이의 편차가 제일 커 유전자의 변이가 다양한 것을 알 수 있었다. 본 연구결과는 기초연구와 항생제 개발 등에 이용될 수 있을 것이다. The clusters of orthologous groups of proteins (COG) algorithm was applied to identify essential proteins in eukaryotes and to measure the degree of conservation. Sixty-three orthologous groups, which were conserved in 66 microbial genomes, enlarged to 104 eukaryotic orthologous groups (KOGs) and 71 KOGs were conserved at the nuclear genome of 7 eucaryotes. Fifty-four of 71 translation-related genes were conserved, highlighting the importance of proteins in modern organisms. Translation initiation factors (KOG0343, KOG3271) and prolyl-tRNA synthetase (KOG4163) showed high conservation based on the distance value analysis. The genes of Caenorhabditis elegans appear to harbor high genetic variation because the genome showed the highest variation at 71 conserved proteins among 7 genomes. The 71 conserved genes will be valuable in basic and applied research, for example, targeting for antibiotic development.

Genomic Analysis of miR-21-3p and Expression Pattern with Target Gene in Olive Flounder

조아라,이희은,김희수 한국유전체학회 2017 Genomics & informatics Vol.15 No.3

MicroRNAs (miRNAs) act as regulators of gene expression by binding to the 3’ untranslated region (UTR) of target genes. They perform important biological functions in the various species. Among many miRNAs, miR-21-3p is known to serve vital functions in development and apoptosis in olive flounder. Using genomic and bioinformatic tools, evolutionary conservation of miR-21-3p was examined in various species, and expression pattern was analyzed in olive flounder. Conserved sequences (5’-CAGUCG-3’) in numerous species were detected through the stem-loop structure of miR-21-3p. Thus, we analyzed target genes of miR-21-3p. Among them, 3’ UTR region of PPIL2 gene indicated the highest binding affinity with miR-21-3p based on the minimum free energy value. The PPIL2 gene showed high expression levels in testis tissue of the olive flounder, whereas miR-21-3p showed rather ubiquitous expression patterns except in testis tissue, indicating that miR-21-3p seems to control the PPIL2 gene expression in a complementary repression manner in various tissues of olive flounder. Taken together, this current study contributes to infer the target gene candidates for the miR-21-3p using bioinformatics tools. Furthermore, our data offers important information on the relationship between miR-21-3p and target gene for further functional study.

Conserved Sequences of Replicase Gene-Mediated Resistance to Potyvirus through RNA Silencing

Li Xu,YunZhi Song,JunHua Zhu,XingQi Guo,ChangXiang Zhu,FuJiang Wen 한국식물학회 2009 Journal of Plant Biology Vol.52 No.6

Nuclear inclusion protein b (NIb) genes of three Potato virus Y isolates PVY-SD1 (O strain), PVY-SD4 (N strain), PVY-SD5 (NTN strain), and Tobacco etch virus isolate TEV-SD1 in Shandong Province were cloned and sequenced. Sequence analysis showed that the sequence homology of the entire NIb gene among the four viruses ranged from 65% to 95%. Hairpin RNA (hpRNA) constructs were designed based on five conserved regions derived from PVY-SD1 and introduced into tobacco plants. After asexual propagation, the transgenic plants were analyzed for resistance to PVY-SD1, PVY-SD4, PVY-SD5, and TEV-SD1. We obtained resistance ratios of 26.2%, 22.7%, 36.4%, 20.3%, and 21.7% to PVY-SD1. When inoculated with the PVY-SD5 virus, the transgenic plants had resistance ratios ranging from 2.4% to 15.9%, but no resistance at all to the other viruses, PVY-SD4 and TEV-SD1. No correlation was found between resistance of transgenic plants and the transgene copy numbers. Northern blot and small interfering RNA (siRNA) analysis demonstrated that the resistance was attributable to RNA silencing. Genetic analysis demonstrated that virus resistance was stably inherited in progeny T1 and T2. These results indicate that the siRNA molecules against conserved regions can confer virus resistance but are restricted to viruses with more than 90% sequence homology.

원핵생물과 공통인 진핵생물의 보존적 유전자 탐색

이동근(Dong-Geun Lee) 한국생명과학회 2013 생명과학회지 Vol.23 No.4

생물들에서 생명의 본질적 기능을 수행하는 단백질들의 종류와 보존성을 밝히기 위해 COG (Clusters of Orthologous Groups of proteins) 알고리즘을 이용하였다. 66종의 미생물에서 보존적인 63개의 ortholog 그룹들은 진핵생물 7종에서 104개의 ortholog들로 확산되었으며, 7종 모두의 핵에 보존적인 KOG (euKaryotic Orthologous Group)은 71개였다. 71개 중 단백질 합성에 관여하는 유전자들이 총 54개로 생명현상에서의 단백질의 중요성을 확인할 수 있었다. Distance value로 보존적 유전자가 생물종 사이에 나타내는 유전자 변이의 정도를 파악하니 ‘Translation initiation factor’인 KOG3403과 KOG3271 그리고 ‘Prolyl-tRNA synthetase’ (KOG4163) 등이 높은 보존성을 보였다. 보존적 KOG들의 평균과 분산으로 유전체 분석을 수행하여 꼬마선충이 KOG 평균사이의 편차가 제일 커 유전자의 변이가 다양한 것을 알 수 있었다. 본 연구결과는 기초연구와 항생제 개발 등에 이용될 수 있을 것이다. The clusters of orthologous groups of proteins (COG) algorithm was applied to identify essential proteins in eukaryotes and to measure the degree of conservation. Sixty-three orthologous groups, which were conserved in 66 microbial genomes, enlarged to 104 eukaryotic orthologous groups (KOGs) and 71 KOGs were conserved at the nuclear genome of 7 eucaryotes. Fifty-four of 71 translation-related genes were conserved, highlighting the importance of proteins in modern organisms. Translation initiation factors (KOG0343, KOG3271) and prolyl-tRNA synthetase (KOG4163) showed high conservation based on the distance value analysis. The genes of Caenorhabditis elegans appear to harbor high genetic variation because the genome showed the highest variation at 71 conserved proteins among 7 genomes. The 71 conserved genes will be valuable in basic and applied research, for example, targeting for antibiotic development.

Functional Prediction of Imprinted Genes in Chicken Based on a mammalian comparative Expression Network

HyoYoung Kim,문선진,김희발 한국유전체학회 2008 Genomics & informatics Vol.6 No.1

Little evidence supports the existence of imprinted genes in chicken. Imprinted genes are thought to be intimately connected with the acquisition of parental resources in mammals; thus, the predicted lack of this type of gene in chicken is not surprising, given that they leave their offspring to their own heritance after conception. In this study, we identified several imprinted genes and their orthologs in human, mouse, and zebrafish, including 30 previously identified human and mouse imprinted genes. Next, using the HomoloGene database, we identified six orthologous genes in human, mouse, and chicken; however, no orthologs were identified for SLC22A18, and mouse Ppp1r9a was not included in the HomoloGene database. Thus, from our analysis, four candidate chicken imprinted genes (IGF2, UBE3A, PHLDA2, and GRB10) were identified. To expand our analysis, zebrafish was included, but no probe ID for UBE3A exists in this species. Thus, ultimately, three candidate imprinted genes (IGF2, PHLDA2, and GRB10) in chicken were identified. GRB10 was not significant in chicken and zebrafish based on the Wilcoxon-Mann- Whitney test, whereas a weak correlation between PHLDA2 in chicken and human was identified from the Spearman's rank correlation coefficient. Significant associations between human, mouse, chicken, and zebrafish were found for IGF2 and GRB10 using the Friedman's test. Based on our results, IGF2, PHLDA2, and GRB10 are candidate imprinted genes in chicken. Importantly, the strongest candidate was PHLDA2.

Functional Prediction of Imprinted Genes in Chicken Based on a Mammalian Comparative Expression Network

Kim, Hyo-Young,Moon, Sun-Jin,Kim, Hee-Bal Korea Genome Organization 2008 Genomics & informatics Vol.6 No.1

Little evidence supports the existence of imprinted genes in chicken. Imprinted genes are thought to be intimately connected with the acquisition of parental resources in mammals; thus, the predicted lack of this type of gene in chicken is not surprising, given that they leave their offspring to their own heritance after conception. In this study, we identified several imprinted genes and their orthologs in human, mouse, and zebrafish, including 30 previously identified human and mouse imprinted genes. Next, using the HomoloGene database, we identified six orthologous genes in human, mouse, and chicken; however, no orthologs were identified for SLC22A18, and mouse Ppp1r9a was not included in the HomoloGene database. Thus, from our analysis, four candidate chicken imprinted genes (IGF2, UBE3A, PHLDA2, and GRB10) were identified. To expand our analysis, zebrafish was included, but no probe ID for UBE3A exists in this species. Thus, ultimately, three candidate imprinted genes (IGF2, PHLDA2, and GRB10) in chicken were identified. GRB10 was not significant in chicken and zebrafish based on the Wilcoxon-Mann-Whitney test, whereas a weak correlation between PHLDA2 in chicken and human was identified from the Spearman's rank correlation coefficient. Significant associations between human, mouse, chicken, and zebrafish were found for IGF2 and GRB10 using the Friedman's test. Based on our results, IGF2, PHLDA2, and GRB10 are candidate imprinted genes in chicken. Importantly, the strongest candidate was PHLDA2.

Changing Environment Promotes Genetic Variation under Stabilizing Selection

Jeung, Mingull 한국유전학회 2004 Genes & Genomics Vol.26 No.4

Populations with diallele two-locus system were simulated with the Monte-Carlo method in order to examine the role of changing environment in retaining genetic variation under stabilizing selection. Without stabilizing selection the heterozygosities of the populations decreased slightly in 100 generations. Stabilizing selection without gene-environment interaction dropped the heterozygosities rapidly and depleted the genetic variation. A changing environment in which two alleles respond to environmental conditions in parallel, however, suppresses the tendency of stabilizing selection that depletes genetic variation. Certain intermediate environmental disturbance relates to community stability, and many endangered species show low genetic heterozygosities. Thus it is necessary to understand what kind of environmental changes will promote genetic variation. Environmental disturbance appropriate to the species to be conserved, therefore, should be incorporated into a preservation plan.