• 제목/요약/키워드: evolution and phylogeny

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Genomic Features of Retroelements and Implications for Human Disease

  • Kim, Heui-Soo
    • Genomics & Informatics
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    • 제3권4호
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    • pp.133-141
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    • 2005
  • Most of the endogenous retroviral genes integrated into the primate genome after the split of New World monkeys in the Oligocene era, approximately 33 million years ago. Because they can change the structure of adjacent genes and move between and within chromosomes they may play important roles in evolutionas well as in many kinds of disease and the creation of genetic polymorphism. Comparative analysis of HERVs (human endogenous retroviruses) and their LTR (long terminal repeat) elements in the primate genomes will help us to understand the possible impact of HERV elements in the evolution and phylogeny of primates. For example, HERV-K LTR and SINE-R elements have been identified that have been subject to recent change in the course of primate evolution. They are specific elements to the human genome and could be related to biological function. The HERV-M element is related to the superfamily of HERV-K and is integrated into the periphilin gene as the truncated form, 5'LTR-gag-pol-3'LTR. PCR and RT-PCR approaches indicated that the insertion of various retrotransposable elements in a common ancestor genome may make different transcript variants in different primate species. Examination of the HERV-W elementrevealed that env fragments were detected on human chromosomes 1, 3-7, 12, 14, 17, 20, and X, whilst the pol fragments were detected on human chromosomes 2-8, 10-15, 20, 21, X, and Y. Bioinformatic blast search showed that almost full-length of the HERV-W family was identified on human chromosomes 1-8, 11-15, 17, 18, 21, and X. Expression analysis of HERV-W genes (gag, pol, and env) in human tissues by RT-PCR indicated that gag and pol were expressed in specific tissues, whilst env was constituitively expressed in all tissues examined. DNA sequence based phylogenetic analysis indicated that the gag, pol and env genes have evolved independently during primate evolution. It will thus be of considerable interest to expand the current HERV gene information of various primates and disease tissues.

A genetic approach to comprehend the complex and dynamic event of floral development: a review

  • Jatindra Nath Mohanty;Swayamprabha Sahoo;Puspanjali Mishra
    • Genomics & Informatics
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    • 제20권4호
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    • pp.40.1-40.8
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    • 2022
  • The concepts of phylogeny and floral genetics play a crucial role in understanding the origin and diversification of flowers in angiosperms. Angiosperms evolved a great diversity of ways to display their flowers for reproductive success with variations in floral color, size, shape, scent, arrangements, and flowering time. The various innovations in floral forms and the aggregation of flowers into different kinds of inflorescences have driven new ecological adaptations, speciation, and angiosperm diversification. Evolutionary developmental biology seeks to uncover the developmental and genetic basis underlying morphological diversification. Advances in the developmental genetics of floral display have provided a foundation for insights into the genetic basis of floral and inflorescence evolution. A number of regulatory genes controlling floral and inflorescence development have been identified in model plants such as Arabidopsis thaliana and Antirrhinum majus using forward genetics, and conserved functions of many of these genes across diverse non-model species have been revealed by reverse genetics. Transcription factors are vital elements in systems that play crucial roles in linked gene expression in the evolution and development of flowers. Therefore, we review the sex-linked genes, mostly transcription factors, associated with the complex and dynamic event of floral development and briefly discuss the sex-linked genes that have been characterized through next-generation sequencing.

Close Relationship Between SARS-Coronavirus and Group 2 Coronavirus

  • Kim, Ok-Ju;Lee, Dong-Hun;Lee, Chan-Hee
    • Journal of Microbiology
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    • 제44권1호
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    • pp.83-91
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    • 2006
  • The sudden appearance and potential lethality of severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) in humans has resulted in a focusing of new attention on the determination of both its origins and evolution. The relationship existing between SARS-CoV and other groups of coronaviruses was determined via analyses of phylogenetic trees and comparative genomic analyses of the coronavirus genes: polymerase (Orflab), spike (S), envelope (E), membrane (M) and nucleocapsid (N). Although the coronaviruses are traditionally classed into 3 groups, with SARS-CoV forming a $4^{th}$ group, the phylogenetic position and origins of SARS-CoV remain a matter of some controversy. Thus, we conducted extensive phylogeneitc analyses of the genes common to all coronavirus groups, using the Neighbor-joining, Maximum-likelihood, and Bayesian methods. Our data evidenced largely identical topology for all of the obtained phylogenetic trees, thus supporting the hypothesis that the relationship existing between SARS-CoV and group 2 coronavirus is a monophyletic one. Additional comparative genomic studies, including sequence similarity and protein secondary structure analyses, suggested that SARS-Co V may bear a closer relationship with group 2 than with the other coronavirus groups. Although our data strongly suggest that group 2 coronaviruses are most closely related with SARS-CoV, further and more detailed analyses may provide us with an increased amount of information regarding the origins and evolution of the coronaviruses, most notably SARS-CoV.

New Records of Three Tintinnopsis Species and Redescription of One Antetintinnopsis Species (Protozoa: Ciliophora) from Coastal Waters of Korea

  • Ji Hye Moon;Jae-Ho Jung
    • Animal Systematics, Evolution and Diversity
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    • 제40권1호
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    • pp.1-15
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    • 2024
  • Our study aimed to investigate the diversity of tintinnid species in Korea by collecting samples from coastal waters. As a result, we identified and redescribed three newly recorded species of the genus Tintinnopsis Stein, 1867 and one previously recorded species of the genus Antetintinnopsis Wang et al., 2021 in Korea. The loricae morphology and molecular phylogeny based on the 18S rDNA sequences of these four were analyzed. Tintinnopsis kiaochowensis Yin, 1956 is characterized by having an irregular collar with spiral turns and an obconical-shaped bowl. Tintinnopsis orientalis Kofoid and Campbell, 1929 is characterized by the inverted bell-shaped lorica with size of 121-140×86-94 ㎛. Tintinnopsis parvula Jörgensen, 1912 is characterized by its narrower collar than bowl and acute angle of the bowl (39-75°). The recorded species, Antetintinnopsis gracilis (Kofoid and Campbell, 1929) Wang et al., 2021 is characterized by a cylindrical collar narrower than the bowl width and with a size of 98-131×37-46 ㎛.

The Complete Mitochondrial Genome of Dendronephthya gigantea (Anthozoa: Octocorallia: Nephtheidae)

  • Park, Eun-Ji;Kim, Bo-A;Won, Yong-Jin
    • Animal Systematics, Evolution and Diversity
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    • 제26권3호
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    • pp.197-201
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    • 2010
  • We sequenced the whole mitochondrial genome of Dendronephthya gigantea (Anthozoa: Octocorallia: Nephteidae), the first mitochondrial genome sequence report in the Family Nephtheidae. The mitochondrial genome of D. gigantea was 18,842 bp in length, and contained 14 protein coding genes (atp6 and 8, cox1-3, cytb, nd1-6 and 4L, and msh1), two ribosomal RNAs, and only one transfer RNA. The gene content and gene order is identical to other octocorals sequenced to date. The portion of the noncoding regions is slightly larger than the other octocorals (5.08% compared to average 3.98%). We expect that the information of gene content, gene order, codon usage, noncoding region and protein coding gene sequence could be used in the further analysis of anthozoan phylogeny.

New Record of a Sea Urchin Echinometra mathaei (Echinoidea: Camarodonta: Echinometridae) from Jeju Island, Korea and Its Molecular Analysis

  • Lee, Taek-Jun;Shin, Sook
    • Animal Systematics, Evolution and Diversity
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    • 제28권3호
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    • pp.178-184
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    • 2012
  • Echinoids were collected at depths of 5-10 m in Munseom, Jeju Island by SCUBA diving on November 23, 2008 and September 15, 2009. Two specimens were identified as Echinometra mathaei (Blainville, 1825) based on morphological characteristics and molecular analyses of mitochondrial cytochrome c oxidase subunit I partial sequences. Echinometra mathaei collected from Korea was redescribed with photographs and was compared with other species from GenBank based on molecular data. Phylogenetic analyses showed that no significant differences were between base sequences of E. mathaei from Korea and that from GenBank. To date, 13 echinoids including this species have been reported from Jeju Island, and 32 echinoids have been recorded in Korea.

아프리카산 Lotobia속(파리목, 애기똥파리과)의 2신종과 속내의 계통분석 및 Lotobia속이 애기똥파리아과 내에서 차지하는 계통학적인 위치 고찰 (Descriptions of Two New Lotobia Species with Reanalysis of Intrageneric Relationships and Discussion of the Systematic Status of Lotobia Lioy within the Subfamily Sphaerocerinae (Dipter : Sphaeroceridae))

  • 한호연;김계중
    • Animal Systematics, Evolution and Diversity
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    • 제12권1호
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    • pp.33-43
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    • 1996
  • 아프리카산 2신종, Lotobia nigeriana와 L. southafricana를 그림과 함께 기재한다. 이 두 종은 형태적으로 상당히 유사하나 색깔과 웅성생식기의 구조에 입각, 구분이 가능하다. 이로서 Lotobia속은 전세계적으로 24종이 기록되며 이들의 종간 유연관계를 분지계통학적으 로 분석하였다. Lotobia속의 synapomorphy들을 다시 제시하였고 근연속들의 계통분류학적 인 현황도 아울러 언급하였다.

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진화하는 셀룰라 오토마타를 이용한 자율이동로봇군의 행동제어 (Behavior Control of Autonomous Mobile Robots using ECANS1)

  • 이동욱;정영준;심귀보
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 G
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    • pp.2183-2185
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    • 1998
  • In this paper, we propose a method of designing neural networks using biological inspired developmental and evolutionary concept. The living things are best information processing system in themselves. One individual is developed from a generative cell. And a species of this individual have adapted itself to the environment by evolution. Ontogeny of organism is embodied in cellular automata and phylogeny of species is realized by evolutionary algorithms. The connection among cells is determined by a rule of cellular automata. In order to obtain the best neural networks in the environment, we evolve the arrangement of initial cells. The cell, that is neuron of neural networks, is modeled on chaotic neuron with firing or rest state like biological neuron. A final output of network is measured by frequency of firing state. The effectiveness of the proposed scheme is verified by applying it to navigation problem of robot.

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Molecular Variation of Endosymbiotic Bacteria Wolbachia in Bemisia tabaci and Related Whiteflies

  • Jahan, S.M. Hemayet;Lee, Kyeong-Yeoll
    • Current Research on Agriculture and Life Sciences
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    • 제30권2호
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    • pp.115-123
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    • 2012
  • Whiteflies harbor several secondary endosymbionts, which are maternally inherited from mother to offspring, that have major effects on host preferences, biology, and evolution. Here, we identified Wolbachia bacteria in sweetpotato whitefly (Bemisia tabaci) as well as whitefly popluations from other countries by comparison of 16S rDNA sequences. Wolbachia were detected in all tested indigenous B. tabaci populations (Bangladesh, Myanmar, Nepal, and the Philippines) as well as Q1 biotype of Korea, whereas they were absent from B biotype of Korea and Q biotype of China. Wolbachia were also detected in all five tested Aleurodicus dispersus populations as well as Tetraleurodes acaciae, whereas they were not detected in all seven Trialeurodes vaporariorum populatuions. In addiiton, Wolbachia were detected in parasitic wasp (Encarsia formosa) of B. tabaci as well as honeybee (Apis mellifera). Among the 19 whitefly populations from different countries, our analysis identified four phylogenetic groups of Wolbachia, thereby demonstrating the high diversity of this genus. Wolbachia phylogeny suggests a correlation of geographical range with ecological variation at the species level.

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진화하는 셀룰라 오토마타 신경망의 하드웨어 구현에 관한 연구 (A Study on Implementation of Evolving Cellular Automata Neural System)

  • 반창봉;곽상영;이동욱;심귀보
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
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    • pp.255-258
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    • 2001
  • This paper is implementation of cellular automata neural network system which is a living creatures' brain using evolving hardware concept. Cellular automata neural network system is based on the development and the evolution, in other words, it is modeled on the ontogeny and phylogeny of natural living things. The proposed system developes each cell's state in neural network by CA. And it regards code of CA rule as individual of genetic algorithm, and evolved by genetic algorithm. In this paper we implement this system using evolving hardware concept Evolving hardware is reconfigurable hardware whose configuration is under the control of an evolutionary algorithm. We design genetic algorithm process for evolutionary algorithm and cells in cellular automata neural network for the construction of reconfigurable system. The effectiveness of the proposed system is verified by applying it to time-series prediction.

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