• Fisheries and Aquatic Sciences
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• 제15권4호
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• pp.325-335
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• 2012

The present study characterized the fast skeletal myosin light chain-2 gene (mlc2f) in the euryhaline Javanese ricefish (Oryzias javanicus: Beloniformes). Coding nucleotide and deduced amino acid sequences of Javanese ricefish mlc2f were well conserved in the vertebrate lineage. Javanese ricefish mlc2f showed a typical seven-exon structure, and its promoter exhibited transcription factor binding motifs common to most muscle-specific genes. However, Javanese ricefish mlc2f also displayed tandem duplications of intronic sequences in both intron 1 and intron 3. Based on quantitative reverse transcription-polymerase chain reaction, the mlc2f transcripts were highly predominant in skeletal muscles of adults and were differentially modulated during embryonic development. Microinjection of the mlc2f promoter-driven red fluorescent protein (RFP) reporter construct successfully exhibited heterologous expression of the fluorescent reporter, primarily in muscular areas of hatchlings, although the distribution pattern of RFP signals was not uniform due to the mosaic nature of the introduced transgene. Data from this study indicate that the Javanese ricefish mlc2f gene has undergone "intra-intronic" duplication events in a species-specific manner and that the mlc2f regulator may also be useful in heterologous expression assays of the skeletal muscles of this species.

• Animal Systematics, Evolution and Diversity
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• 제8권2호
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• pp.177-182
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• 1992

1986년 4월부터 1991년 2월까지 한국의 서남해로 유입하는 하천과 인접 도서지방에 서식하는 송사리 Oryzias latipes의 표본을 조사한 바, 조사수역의 모든 표본은 척추골 수가 28-31개이고, 가슴지느러미 기조수는 9개이며, 2n 염색체 수가 46개 이었다. 이러한 특징은 동해로 유입하는 하천과 남해의 인접 도서지방에 분포하는 O. latipes latipes와는 구별되고, 중국산 O.latipes sinensis와 일치되어 한국 미기록 아종으로 보고하고 이 아종의 국명은 대륙송사리로 명명한다.

• Fisheries and Aquatic Sciences
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• 제15권4호
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• pp.317-324
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• 2012

We characterized the cytoskeletal beta-actin (${\beta}$-ACT) gene (actb) and its 5'-upstream regulatory region in the Javanese ricefish Oryzias javanicus. The gene and protein structures were deduced from amino acid sequences of the actb gene and conserved in the teleost lineage. The O. javanicus actb gene has common transcription factor binding motifs in its regulatory region found in teleostean orthologues. Following quantitative reverse transcription-PCR, actb gene transcripts were detected in all tissues examined; however, the basal expression levels were different. During early development, O. javanicus actb mRNA levels showed a gradual increase and peaked between late somitogenesis and the heartbeat stage. Microinjection of O. javanicus embryos with the actb gene promoter-driven red fluorescent protein (RFP) gene reporter vector showed a ubiquitous distribution of RFP signals, although most exhibited a mosaic pattern of transgene expression. A small number of microinjected embryos displayed a wide distribution of RFP signals over their entire body, which resembled the expression pattern of endogenous actb. Data from this study provide a basis to develop a transgenic system with ubiquitous expression of foreign genes in O. javanicus.

• 한국어류학회지
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• 제18권3호
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• pp.163-169
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• 2006

한국산 송사리속 어류 2종 Oryzias latipes와 O. sinensis에 대한 분포역을 조사한 결과 O.sinensis는 서해안과 그 내륙지역에 제한되어 분포한 반면에 O. latipes는 한반도의 대부분 지역에 분포하고 있었고, 특히 서해안 지역의 대천지역에서는 두 종이 혼서하고 있었다. 또한 송사리와 대륙송사리는 척추골수와 새파수에서 잘 구분되고 있는데 척추골 수에서는 송사리가 평균 31개, 대륙송사리가 평균 30개이었으며 새파수는 송사리가 평균 15개, 대륙송사리가 평균 12개를 갖는다. 또한 체측반문에 있어서 송사리는 체측에 반점들이 존재하였지만 대륙송사리는 없었으며, 산란시기에 송사리는 배지느러미와 뒷지느러미에 노란색을 띠는 반면에 대륙송사리는 검은색을 띠고 있었다.

• Fisheries and Aquatic Sciences
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• 제14권2호
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• pp.93-104
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• 2011

Two hepcidin paralogs (ojhamp1 and ojhamp2) were isolated and characterized from a euryhaline Javanese ricefish (Oryzias javanicus: Beloniformes). The ojhamp1 cDNA encoded 90 or 91 amino acids (aa) of a typical HAMP1 preproprotein. This preproprotein is believed to cleave and yield the 66 or 67 aa-proprotein, followed by the 26 aa-mature peptide, composed of 8 conserved cysteine residues and the QSHL amino terminal motif. The ojhamp2 cDNA encoded 89 aa of HAMP2 preproprotein, cleaved to yield a 65 aa proprotein, and subsequently the 25 aa-mature peptide. The mature OJHAMP1 possessed a cationic isoelectric point (pI), whereas OJHAMP2 had an anionic charge. At the genomic level, both ojhamp1 and ojhamp2 share a conserved tripartite structure (three exons interrupted by two introns) with other vertebrate hepcidin genes. However, the ojhamp1 was shown to exist as two distinct mRNA species, encoding 90 or 91 aa, due to alternative splicing at the junction site between intron I and exon II. Both ojhamp1 and ojhamp2 transcripts were detected in a wide range of tissue types with varying levels of basal expression, although the highest expression was observed in the liver for both isoforms. Transcriptional response to bacterial challenge using Edwardsiella tarda showed that ojhamp1 was moderately upregulated in the liver but remained unchanged in the kidney. However, the ojhamp2 was significantly suppressed in both the kidney and liver, suggesting a potential diversification between the two paralogs.

• 대한수의학회지
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• 제57권1호
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• pp.67-69
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• 2017

In the present study, Aeromonas (A.) hydrophila was isolated from a captive-bred adult freshwater stingray (Potamotrygon motoro) reared at a commercial aquarium in Korea. The stingray had bites on its fins, hemorrhages on the ventral part, and congested internal organs. A bacterium was isolated from kidney and subsequently identified as A. hydrophila. Based on phylogenetic analysis results, the isolate in the present study (SNUAh-LA1) was most closely related to A. hydrophila AH10 (China) and A. hydrophila AKR1 (Korea). It is most likely that the pathogen infection resulted from Potamotrygon motoro cohabiting with ricefish (Oryzias latipes).