• Title/Summary/Keyword: evolution and phylogeny

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Phylogeny, host-parasite relationship and zoogeography

  • Hasegawa, Hideo
    • Parasites, Hosts and Diseases
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    • v.37 no.4
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    • pp.197-213
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    • 1999
  • Phylogeny is the evolutionary history of a group or the lineage of organisms and is reconstructed based on morphological, molecular and other characteristics. The genealogical relationship of a group of taxa is often expressed as a phylogenetic tree. The difficulty in categorizing the phylogeny is mainly due to the existence of frequent homoplasies that deceive observers. At the present time, cladistic analysis is believed to be one of the most effective methods of reconstructing a phylogenetic tree. Excellent computer program software for phylogenetic analysis is available. As an example, cladistic analysis was applied for nematode genera of the family Acuariidae, and the phylogenetic tree formed was compared with the system used currently. Nematodes in the genera Nippostrongylus and Heligmonoides were also analyzed, and the validity of the reconstructed phylogenetic trees was observed from a zoogeographical point of view. Some of the theories of parasite evolution were briefly reviewed as well. Coevolution of parasites and humans was discussed with special reference to the evolutionary relationship between Enterobius and primates.

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African great apes (chimpanzee and gorilla) : feature, phylogeny and evolution (아프리카 대형 유인원(침팬지, 고릴라) : 특징, 계통 및 진화)

  • 홍경원;김희수
    • Journal of Life Science
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    • v.13 no.2
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    • pp.175-183
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    • 2003
  • The chimpanzee and gorilla are classified into hominidae, catarrhini, primates. These species are originated from Africa, so called African great apes. Recently, primatologists have classified that there are 2 species 5 subspecies of the chimpanzee and gorilla, respectively. Since the human genome project has been finished, the chimpanzee genome project has been launched to understand human evolution and genetic diseases. The sequences of chimpanzee chromosome 22 homologous to human chromosome 21 were completed, and then the Y chromosome of chimpanzee is being analyzed. Comparative analysis of human, chimpanzee and gorilla could provide the key for understanding of various human diseases and human origin. By detecting human specific-functional genes or mobile genetic elements (HERV, LINE, SINE) through primate research, we could understand what is human being\ulcorner gradually, For these comparative researches, we summarized fundamental knowledge of the feature, phylogeny and evolution of African great apes including humans.

Sirtuin/Sir2 Phylogeny, Evolutionary Considerations and Structural Conservation

  • Greiss, Sebastian;Gartner, Anton
    • Molecules and Cells
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    • v.28 no.5
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    • pp.407-415
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    • 2009
  • The sirtuins are a protein family named after the first identified member, S. cerevisiae Sir2p. Sirtuins are protein deacetylases whose activity is dependent on $NAD^+$ as a cosubstrate. They are structurally defined by two central domains that together form a highly conserved catalytic center, which catalyzes the transfer of an acetyl moiety from acetyllysine to $NAD^+$, yielding nicotinamide, the unique metabolite O-acetyl-ADP-ribose and deacetylated lysine. One or more sirtuins are present in virtually all species from bacteria to mammals. Here we describe a phylogenetic analysis of sirtuins. Based on their phylogenetic relationship, sirtuins can be grouped into over a dozen classes and subclasses. Humans, like most vertebrates, have seven sirtuins: SIRT1-SIRT7. These function in diverse cellular pathways, regulating transcriptional repression, aging, metabolism, DNA damage responses and apoptosis. We show that these seven sirtuins arose early during animal evolution. Conserved residues cluster around the catalytic center of known sirtuin family members.

Ribosomal Protein S4 Genes in Macaca fuscata: Sequence, Evolution, and Phylogeny

  • Kim, Heui-Soo
    • Journal of Life Science
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    • v.11 no.1
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    • pp.34-38
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    • 2001
  • The cDNA encoding ribosomal protein S4(RPS 4) from an ovary cDNA library of the Japanese monkey (Macaca fuscata) was cloned and sequenced. The RPS4X gene from monkey X chromosome encodes a deduced protein of 263 amino acids and share 99.1% cDNA sequence similarity and 100% amino acid sequence identify with the human RPS4X. Rate of synonymous substitution was higher in RPS4Y than in RPS4X in comparison to the monkey and human. The ratio of synonymous and nonsynonymous substitutions per site indicated that directional selection has nor occurred in RPS4 genes. Phylogenetic analysis using the neighbor-joining method revealed that X and Y-linked RPS4 genes have evolved independently.

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