• The Korea Genome Conference
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• 2004.07a
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• pp.34.2-34.2
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• 2004

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.05a
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• pp.62-62
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• 2004

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.198-198
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• 2021

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.10a
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• pp.102-102
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• 2003

• Proceedings of the Korean Society of Potoscience Conference
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• 2006.06a
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• pp.57-57
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• 2006

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.04a
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• pp.199-199
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• 2005

• Genomics & Informatics
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• v.21 no.4
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• pp.47.1-47.12
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• 2023

Silver barb (Barbonymus gonionotus) is among the most economically important freshwater fish species in Thailand. It ranks fourth in economic value and third in production weight for fisheries and culture in Thailand. An XX/XY sex-determination system based on gynogenesis was previously reported for this fish. In this study, the molecular basis underlying the sex-determination system was further investigated. Genome-wide single-nucleotide polymorphism data were generated for 32 captive-bred silver barb individuals, previously scored by phenotypic sex, to identify sex-linked regions associated with sex determination. Sixty-three male-linked loci, indicating putative XY chromosomes, were identified. Male-specific loci were not observed, which indicates that the putative Y chromosome is young and the sex determination region is cryptic. A homology search revealed that most male-linked loci were homologous to the Mariner/Tc1 and Gypsy transposable elements and are probably the remnants of an initial accumulation of repeats on the Y chromosome from the early stages of sex chromosome differentiation. This research provides convincing insights into the mechanism of sex determination and reveals the potential sex determination regions in silver barb. The study provides the basic data necessary for increasing the commercial value of silver barbs through genetic improvements.

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.44.2-44.2
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• 2006

• Genomics & Informatics
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• v.4 no.2
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• pp.77-79
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• 2006

In order to identify novel proapoptotic genes, we screened approximately 1,000 hypothetical genes whose functions are completely unknown. After these genes were transiently expressed in HeLa cells, their nuclei images were captured using automated high-speed fluorescence microscope, through which the ratio of apoptotic nuclei was estimated. We selected genes that induce greater than 3-fold increase in apoptotic nuclei compared to that of the vector control. The candidate proapoptotic genes were sequenced and their effects on cell death were further confirmed by the additional assay, DNA fragmentation ELISA. Finally, we were able to identify 4 full-length hypo-thetical genes with proapoptotic activity.

• Genomics & Informatics
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• v.21 no.3
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• pp.39.1-39.15
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• 2023

DNA barcoding without assessing reliability and validity causes taxonomic errors of species identification, which is responsible for disruptions of their conservation and aquaculture industry. Although DNA barcoding facilitates molecular identification and phylogenetic analysis of species, its availability in clariid catfish lineage remains uncertain. In this study, DNA barcoding was developed and validated for clariid catfish. 2,970 barcode sequences from mitochondrial cytochrome c oxidase I (COI) and cytochrome b (Cytb) genes and D-loop sequences were analyzed for 37 clariid catfish species. The highest intraspecific nearest neighbor distances were 85.47%, 98.03%, and 89.10% for COI, Cytb, and D-loop sequences, respectively. This suggests that the Cytb gene is the most appropriate for identifying clariid catfish and can serve as a standard region for DNA barcoding. A positive barcoding gap between interspecific and intraspecific sequence divergence was observed in the Cytb dataset but not in the COI and D-loop datasets. Intraspecific variation was typically less than 4.4%, whereas interspecific variation was generally more than 66.9%. However, a species complex was detected in walking catfish and significant intraspecific sequence divergence was observed in North African catfish. These findings suggest the need to focus on developing a DNA barcoding system for classifying clariid catfish properly and to validate its efficacy for a wider range of clariid catfish. With an enriched database of multiple sequences from a target species and its genus, species identification can be more accurate and biodiversity assessment of the species can be facilitated.