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Chang-Bae Kim

Publications and source records attributed to Chang-Bae Kim.

15 recordsLinked to original sources
PubMed2006

DNA barcoding Korean birds.

DNA barcoding, an inventory of DNA sequences from a standardized genomic region, provides a bio-barcode for identifying and discovering species. Several recent studies suggest that the sequence diversity in a 648 bp region of the mitochondrial gene for cytochrome c oxi- dase I (COI) might serve as a DNA barcode for identify- ing animal species such as North American birds, in- sects and fishes. The present study tested the effective- ness of a COI barcode in discriminating Korean bird species. We determined the 5' terminus of the COI bar- code for 92 species of Korean birds and found that spe- cies identification was unambiguous; the genetic differ- ences between closely related species were, on average, 25 times higher than the differences within species. We identified only one misidentified species out of 239 specimens in a genetic resource bank, so confirming the accuracy of species identification in the banking system. We also identified two potential composite species, calling for further investigation using more samples. The finding of large COI sequence differences between species confirms the effectiveness of COI barcodes for identifying Korean bird species. To bring greater reliability to the identification of species, increased in- tra- and interspecies sampling, as well as supplementa- tion of the mitochondrial barcodes with nuclear ones, is needed.

Animals↗
PubMed2006

Sequence-level analysis of the diploidization process in the triplicated FLOWERING LOCUS C region of Brassica rapa.

Strong evidence exists for polyploidy having occurred during the evolution of the tribe Brassiceae. We show evidence for the dynamic and ongoing diploidization process by comparative analysis of the sequences of four paralogous Brassica rapa BAC clones and the homologous 124-kb segment of Arabidopsis thaliana chromosome 5. We estimated the times since divergence of the paralogous and homologous lineages. The three paralogous subgenomes of B. rapa triplicated 13 to 17 million years ago (MYA), very soon after the Arabidopsis and Brassica divergence occurred at 17 to 18 MYA. In addition, a pair of BACs represents a more recent segmental duplication, which occurred approximately 0.8 MYA, and provides an exception to the general expectation of three paralogous segments within the B. rapa genome. The Brassica genome segments show extensive interspersed gene loss relative to the inferred structure of the ancestral genome, whereas the Arabidopsis genome segment appears little changed. Representatives of all 32 genes in the Arabidopsis genome segment are represented in Brassica, but the hexaploid complement of 96 has been reduced to 54 in the three subgenomes, with compression of the genomic region lengths they occupy to between 52 and 110 kb. The gene content of the recently duplicated B. rapa genome segments is identical, but intergenic sequences differ.

Brassica rapa↗
PubMed2006

Molecular evolution of the periphilin gene in relation to human endogenous retrovirus m element.

HERV-M (human endogenous retrovirus M), related to the super family of HERV-K, has a methionine (M) tRNA primer-binding site, and is located within the periphilin gene on human chromosome 12q12. HERV-M has been integrated into the periphilin gene as the truncated form, 5'LTR-gag-pol-3'LTR. Polymerase chain reaction (PCR) and reverse transcription-polymerase chain reaction (RT-PCR) approaches were conducted to investigate its evolutionary origins. Interestingly, the insertion of retroelements in a common ancestor genome can make different transcript variants in different species. In the case of the periphilin gene, human (10 variants) and mouse (2 variants) lineages show different transcript variants. Insertion of HERV-M (variant 1-3) could affect the protein-coding region. Also, Alusq/x (variant 4-9) and L1ME4a (mammalian-wide subfamilies of LINE-1) (variant 10) in humans and SINE (short interspersed repetitive element) and RLTR15 (the mouse putative long terminal repeat) (variant 2) in mice could be driving forces in transcript diversification of the periphilin gene during mammalian evolution. The HERV-M derived transcripts (variant 1-3) were expressed in different human tissues, whereas they were not detected in crab-eating monkey and squirrel monkey tissues by RT-PCR amplification. Taken together, HERV-M seems to have been integrated into our common ancestor genome after the divergence of simians and prosimians, and then was actively expressed during hominoid evolution.

Alternative Splicing↗
PubMed2006

The mitochondrial genome of the smaller tea tortrix Adoxophyes honmai (Lepidoptera: Tortricidae).

Almost complete mitochondrial genome from a representative of an insect order Lepidoptera, the smaller tea tortrix Adoxophyes honmai was determined. The 15,680 bp long A. honmai genome encodes 13 putative proteins, two ribosomal RNAs and 22 tRNAs. The nucleotide sequences of A. honmai mitochondrial DNA have been compared with those of five species from the Lepidoptera and insects in the other orders that are available in the databases. The orientation and gene order of A. honmai is almost same to that of other insects with a few minor exceptions in the order of tRNAs and distribution of non-coding regions. Nucleotide composition, amino acid composition and codon usage are in the range of values estimated from other insect mitogenomes. In AT rich region of A. honmai, tandem reiterations are observed with repeats of TAA. In a preliminary phylogenetic analysis based on the concatenated 7 protein coding genes, A. honmai, an apoditrysian tortricid moth joined basally within the monophyly of Lepidoptera, supporting its relationship with other more derived species including obtectomeran Ostrinia species.

Animals↗
PubMed2005

A combined approach for locating box H/ACA snoRNAs in the human genome.

A novel combined method for locating box H/ACA small nucleolar RNAs (snoRNAs) is described, together with a software tool. The method adopts both a probabilistic hidden Markov model (HMM) and a minimum free energy (MFE) rule, and filters possible candidate box H/ACA snoRNAs obtained from genomic DNA sequences. With our novel method 12 known box H/ACA snoRNAs, and one strong candidate were identified in 30 nucleolar protein genomic sequences.

Algorithms↗
PubMed2005

Molecular phylogeny and geography of Korean medaka fish (Oryzias latipes).

The phylogeny and geography of the medaka (Oryzias latipes) populations of Korea were investigated by analyzing sequence data for the mitochondrial control region. From the 41 haplotypes including 25 Korean haplotypes detected in 64 Korean specimens and data for the Japanese and Chinese populations, phylogenetic and nested clade analyses were executed to examine the phylogeny of haplogroups and the relation of the genetic architecture of the haplotypes to the historical geography of the Korean medaka fish. The analyses suggest that there are two very distinct lineages of Korean medaka, and that these result from reproductive isolation mechanisms due to geographic barriers. The southeastern lineage has experienced recent range expansion to the western region. The northwestern lineage, sister to Chinese populations, showed evidence of internal range expansion with shared haplotypes.

Animals↗
PubMed2005

Correlation of the rates of solvolysis of 2-phenyl-2-ketoethyl bromide and tosylate.

[reaction: see text] The extended Grunwald-Winstein equation has been applied to the specific rates of solvolysis of 2-phenyl-2-ketoethyl bromide and tosylate and the correlation parameters are consistent with an S(N)2 mechanism over the full range of solvents. The k(OTs)/k(Br) ratios are close to unity, consistent with this assignment. Comparisons with the specific rates of solvolysis of 2-phenylethyl bromide and methyl tosylate show only a modest influence upon introduction of the carbonyl group.

Journal Article↗
PubMed2005

Evolution of microRNAs located within Hox gene clusters.

MicroRNAs (miRNAs) form an abundant class of non-coding RNA genes that have an important function in post-transcriptional gene regulation and in particular modulate the expression of developmentally important transcription factors including Hox genes. Two families of microRNAs are genomically located in intergenic regions in the Hox clusters of vertebrates. Here we describe their evolution in detail. We show that the micro RNAs closely follow the patterns of protein evolution in the Hox clusters, which is characterized by cluster duplications followed by differential gene loss.

Animals↗
PubMed2004

The complete mitochondrial genome of the javeline goby Acanthogobius hasta (Perciformes, Gobiidae) and phylogenetic considerations.

We isolated Acanthogobius hasta mitochondrial DNA by long-polymerase chain reaction (long-PCR) with conserved primers, and sequenced this mitogenome with primer walking. The resultant A. hasta mitochondrial DNA sequence was found to consist of 16,663 bp with a structural organization conserved relative to that of other fish. In this paper, we report the basic characteristics of the A. hasta mitochondrial genome including structural organization, base composition of rRNAs and the tRNAs and protein-encoding genes, and characteristics of mitochondrial tRNAs. These findings are applicable to molecular phylogenetics in the suborder Gobioidei.

Animals↗
PubMed2004

Molecular phylogenetic status of the Korean goral and Japanese serow based on partial sequences of the mitochondrial cytochrome b gene.

To investigate the molecular phylogenetic status of the Korean goral, Nemorhaedus caudatus raddeanus, and Japanese serow, Capricornis crispus, we determined partial sequences of the mitochondrial cytochrome b gene of twelve Korean gorals and sixteen Japanese serows, and compared them with those of the major lineages of Rupicaprini species including two other Nemorhaedus species and two other Capricornis species. The Korean gorals examined possessed two haplotypes with only one nucleotide difference between them, while the Japanese serows showed slightly higher sequence diversity with five haplotypes. Genetic distances and molecular phylogenetic trees indicated that there is considerable genetic divergence between the Korean goral and N. caudatus (the Chinese goral) [Groves and Shields (1996)], but virtually none between Korean and Russian gorals. The Korean and Russian gorals may therefore be distinct from the Chinese goral. The data highlight the importance of conservation of the goral populations of these regions, and the need to reconsider the taxonomic status of Korean and Russian gorals. Our study also clearly demonstrated sufficient genetic distance between serows and gorals to justify their assignment to separate genera. Of the three species of Capricornis, the Formosan serow, C. swinhoei is more closely related to C. sumatraensis than to the Japanese serow, suggesting that the Formosan serow is a distinct species. Preliminary data on intraspecific genetic variation in the Japanese serow are also presented.

Animals↗
PubMed2003

Hox genes from the earthworm Perionyx excavatus.

The Hox genes of the oligochaete, Perionyx excavatus, were surveyed using PCR and phylogenetic analysis. We were able to identify 11 different Hox gene fragments. Comparative and phylogenetic analyses revealed that this oligochaete would have at least five Hox genes of the anterior group, including three copies of labial-type, five of the central group and one of the posterior group. This is the first report regarding sequence information and phylogenetic analysis of Hox genes in the earthworm.

Animals↗
PubMed2003

Phylogenetic analysis of the mammalian Hoxc8 non-coding region.

The non-coding intergenic regions of Hox genes are remarkably conserved among mammals. To determine the usefulness of this sequence for phylogenetic comparisons, we sequenced an 800-bp fragment of the Hoxc9-Hoxc8 intergenic region from several species belonging to different mammalian clades. Results obtained from the phylogenetic analysis are congruent with currently accepted mammalian phylogeny. Additionally, we found a TC mini satellite repeat polymorphism unique to felines. This polymorphism may serve as a useful marker to differentiate between mammalian species or as a genetic marker in feline matings. This study demonstrates usefulness of a comparative approach employing non-coding regions of Hox gene complexes.

Animals↗
PubMed2002

Characterization of Hox genes in the bichir, Polypterus palmas.

It has been suggested that the increase in the number of Hox genes may have been one of the key events in vertebrate evolution. Invertebrates have one Hox cluster, while mammals have four. Interestingly, the number of Hox gene clusters is greater in the teleost fishes, zebrafish and medaka, than in mouse and human. The greater number of Hox clusters in the teleosts suggests that Hox gene duplication events have occurred during the radiation of ray-finned fishes. The question is when the Hox gene duplication event(s) that lead to seven Hox clusters in the teleosts actually occurred. We have addressed this question by studying the Hox genes in the bichir, Polypterus palmas. A preliminary PCR-estimation of the number of Hox genes suggests that Polypterus has five different Hox9 cognate group genes, which may be an indication of more than four Hox clusters in the bichir.

Amino Acid Sequence↗
PubMed2002

Molecular evolution of the HoxA cluster in the three major gnathostome lineages.

The duplication of Hox clusters and their maintenance in a lineage has a prominent but little understood role in chordate evolution. Here we examined how Hox cluster duplication may influence changes in cluster architecture and patterns of noncoding sequence evolution. We sequenced the entire duplicated HoxAa and HoxAb clusters of zebrafish (Danio rerio) and extended the 5' (posterior) part of the HoxM (HoxA-like) cluster of horn shark (Heterodontus francisci) containing the hoxa11 and hoxa13 orthologs as well as intergenic and flanking noncoding sequences. The duplicated HoxA clusters in zebrafish each house considerably fewer genes and are dramatically shorter than the single HoxA clusters of human and horn shark. We compared the intergenic sequences of the HoxA clusters of human, horn shark, zebrafish (Aa, Ab), and striped bass and found extensive conservation of noncoding sequence motifs, i.e., phylogenetic footprints, between the human and horn shark, representing two of the three gnathostome lineages. These are putative cis-regulatory elements that may play a role in the regulation of the ancestral HoxA cluster. In contrast, homologous regions of the duplicated HoxAa and HoxAb clusters of zebrafish and the HoxA cluster of striped bass revealed a striking loss of conservation of these putative cis-regulatory sequences in the 3' (anterior) segment of the cluster, where zebrafish only retains single representatives of group 1, 3, 4, and 5 (HoxAa) and group 2 (HoxAb) genes and in the 5' part of the clusters, where zebrafish retains two copies of the group 13, 11, and 9 genes, i.e., AbdB-like genes. In analyzing patterns of cis-sequence evolution in the 5' part of the clusters, we explicitly looked for evidence of complementary loss of conserved noncoding sequences, as predicted by the duplication-degeneration-complementation model in which genetic redundancy after gene duplication is resolved because of the fixation of complementary degenerative mutations. Our data did not yield evidence supporting this prediction. We conclude that changes in the pattern of cis-sequence conservation after Hox cluster duplication are more consistent with being the outcome of adaptive modification rather than passive mechanisms that erode redundancy created by the duplication event. These results support the view that genome duplications may provide a mechanism whereby master control genes undergo radical modifications conducive to major alterations in body plan. Such genomic revolutions may contribute significantly to the evolutionary process.

Amino Acid Motifs↗