• Molecules and Cells
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• v.37 no.10
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• pp.705-712
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• 2014

The early steps of neural development in the vertebrate embryo are regulated by sets of transcription factors that control the induction of proliferative, pluripotent neural precursors, the expansion of neural plate stem cells, and their transition to differentiating neural progenitors. These early events are critical for producing a pool of multipotent cells capable of giving rise to the multitude of neurons and glia that form the central nervous system. In this review we summarize findings from gain- and loss-of-function studies in embryos that detail the gene regulatory network responsible for these early events. We discuss whether this information is likely to be similar in mammalian embryonic and induced pluripotent stem cells that are cultured according to protocols designed to produce neurons. The similarities and differences between the embryo and stem cells may provide important guidance to stem cell protocols designed to create immature neural cells for therapeutic uses.

• BMB Reports
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• v.49 no.2
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• pp.93-98
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• 2016

Germline stem cells (GSCs) are the best understood adult stem cell types in the nematode Caenorhabditis elegans, and have provided an important model system for studying stem cells and their cell fate in vivo, in mammals. In this review, we propose a mechanism that controls GSCs and their cell fate through selective activation, repression and mobilization of the specific mRNAs. This mechanism is acutely controlled by known signal transduction pathways (e.g., Notch signaling and Ras-ERK MAPK signaling pathways) and P granule (analogous to mammalian germ granule)-associated mRNA regulators (FBF-1, FBF-2, GLD-1, GLD-2, GLD-3, RNP-8 and IFE-1). Importantly, all regulators are highly conserved in many multi-cellular animals. Therefore, GSCs from a simple animal may provide broad insight into vertebrate stem cells (e.g., hematopoietic stem cells) and their cell fate specification.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.603-609
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• 2011

Telomeres are special structures at the ends of eukaryotic chromosomes. Vertebrate telomeres consist of tandem repeats of conserved TTAGGG sequence and associated proteins. Birds are interesting models for molecular studies on aging and cellular senescence because of their slow aging rates and longer life spans for their body size. In this longitudinal study, we explored the possibility of using telomeres as an age-marker to predict age in Single Comb White Leghorn layer chickens. We quantified the relative amount of telomeric DNA in isolated peripheral blood lymphocytes by the Quantitative Fluorescence in situ Hybridization technique on interphase nuclei (IQ FISH) using telomere-specific DNA probes. We found that the amount of telomeric DNA (ATD) reduced significantly with an increase in chronological age of the chicken. Especially, the telomere shortening rates are greatly increased in growing individuals compared to laying and old-aged individuals. Therefore, using the ATD values obtained by IQ FISH we established the possibility of age prediction in chickens based on the telomere theory of aging. By regression analysis of the ATD values at each age interval, we formulated an equation to predict the age of chickens. In conclusion, the telomeric DNA values by IQ FISH analyses can be used as an effective age-marker in predicting the chronological age of chickens. The study has implications in the breeding and population genetics of poultry, especially the reproductive potential.

• Journal of fish pathology
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• v.1 no.1
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• pp.59-64
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• 1988

Anaesthetis have been in use for a long time in aquaculture because working with anaesthetized aquatic vertebrate was found to be advantages in many technical operations. However, most anaesthetics applied at present have a strong toxic effect on fish. Lidocaine belong to a group of anaesthetics which are used in human medicine. This chemical was evaluated as anaesthetics for seven species of fishes. The response varied for seven test species. Lidocaine was preferable to other conventional fish anaesthetics since it is cheap, safe and convenient to use.

• Biomedical Science Letters
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• v.16 no.1
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• pp.33-38
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• 2010

Culinary herbs and spices have received much attention since they contain high concentrations of bioactive ingredients for antioxidant and anti-inflammatory activities. Protection effect of the herb and spice against acute alcohol consumption has been investigated using zebrafish as a vertebrate model. During 30 days bathed in water containing 1% Et-OH and the designated herb or spice, the survival rate of the Et-OH group was decreased sharply (up to 20% at 10 days). The cinnamon-fed group showed the highest and longer survival rate up to 80% up to for 30 days under the presence of Et-OH, while clove-fed group showed 40% survival rate for 25 days. Et-OH group serum exhibited the weakest antioxidant ability from ferric ion removal ability (FRA) assay; FRA ability was increased in the cinnamon-fed group up to 414%, while the clove and laurel group increased 256% and 309%, respectively. Histologic observation and Oil-red O staining showed hepatic tissue damage was severe in the Et-OH group. The cinnamon- or clove-fed group showed much ameliorated hepatic tissue morphology with minimized steatosis. The cinnamon- or clove-fed group showed lower serum GOT and GPT levels than the Et-OH group. Among hepatic tissue extract, the clove-fed group exhibited the lowest level of GOT and GPT. These results suggest that consumption of cinnamon and clove might be beneficial to attenuate progress of acute fatty liver change by alcohol consumption.

• Korean Journal of Veterinary Service
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• v.33 no.4
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• pp.361-366
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• 2010

This study was carried out to investigate the characters of short-tailed dogs (DongGyeong dogs) with anatomical insights, molecular genetics in Gyeongju. The present study was conducted to further characterize of short-tailed dog population in Gyeongju. The short-tailed dog was analyzed in the distribution of 55 individual. The anatomical insights were by x-ray. For discovery of specific genes expressions were measured by Hot-start PCR analysis. Anatomy survey, the number of vertebral typical consists of more than 20. 88.9% of short-tailed dog populations consists of 3-8 vertebrates. The 54 individuals of the 47 observe the vestigial tailed of the sacrum. No detected sacrococcygeal vertebrae degradation individuals were malformation defects. The 3 genes were DEGs (differentially expressed genes) in Dong-Gyeong dogs. We succeeded in finding 3 novel DongGyeong dogs specific genes by using Hot-start PCR analysis, this study suggests that these novel genes may play role (s) in DongGyeong dogs.

• Journal of Ecology and Environment
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• v.40 no.1
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• pp.1-4
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• 2016

Recent ocean warming near the Korean peninsula and our lack of knowledge of an important vertebrate group, the sea snakes, encouraged us to clarify this part of Korea's regional fauna. We re-examined photographs that had been used to report the slender-necked sea snake (Hydrophis melanocephalus) in 1995. We discovered it was misidentified. To determine the correct identity of the sea snake, we studied 13 original photographs taken at the collecting site in Sooyoung Bay, Busan-si, in 1995 and determined the snake to be Laticauda semifasciata based on enlarged ventral scales, definitive for Laticaudinae sea snakes, and internasal scales, pale blue body color, divided rostral scale, and evident "V"-shaped stripes on the body trunk, definitive for L. semifasciata. Therefore, the snake caught 30 years ago in Korean waters should be considered the first record of a Laticaudinae sea snake in Korean waters. L. semifasciata is listed as near threatened setting the stage for urgently needed studies of sea snakes in Korea and supporting those currently underway.

• Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.185-193
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• 2009

A complete cDNA, which encodes for a myostatin-like protein (Es-MSTN), was isolated from the Chinese mitten crab, Eriocheir sinensis. Es-MSTN was composed of 2,397 nucleotides and the open reading frame (ORF) specified a protein containing 468 amino acids. Es-MSTN exhibited 32% amino acid sequence identity and 52% similarity to human myostatin. Multiple sequence alignment analysis indicated that Es-MSTN possessed the conserved proteolytic cleavage site (RXXR) for maturation of the protein and nine cysteine residues for disulfide bridges. Besides the conserved structural features, Es-MSTN also exhibits its unique characters; a longer N-terminal domain which is involved in protein folding and latent form of myostatin and absence of the cleavage site for BMP-1/tolloid family of metalloproteinase to activate mature myostatin. Phylogenetic analysis suggests that Es-MSTN showed the closely related to both vertebrate myostatin and GDF11. Es-MSTN is expressed highly in the claw muscle, leg muscle, thoracic muscle and heart, and moderately in the hindgut suggesting that Es-MSTN may play important roles in the muscle tissues. As homolog of mammalian myostatin and GDF11, Es-MSTN may be involved in development of muscular tissue and further study will help to produce high-quality seafood.

• Fisheries and Aquatic Sciences
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• v.15 no.4
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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.

• Fisheries and Aquatic Sciences
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• v.20 no.12
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• pp.31.1-31.11
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• 2017

Background: Liver-expressed antimicrobial peptide-2 (LEAP-2) is an important component of innate immune system in teleosts. In order to understand isoform-specific involvement and regulation of LEAP-2 genes in mud loach (Misgurnus mizolepis, Cypriniformes), a commercially important food fish, this study was aimed to characterize gene structure and expression characteristics of two paralog LEAP-2 isoforms. Results: Mud loach LEAP-2 isoforms (LEAP-2A and LEAP-2B) showed conserved features in the core structure of mature peptides characterized by four Cys residues to form two disulfide bonds. The two paralog isoforms represented a tripartite genomic organization, known as a common structure of vertebrate LEAP-2 genes. Bioinformatic analysis predicted various transcription factor binding motifs in the 5'-flanking regions of mud loach LEAP-2 genes with regard to development and immune response. Mud loach LEAP-2A and LEAP-2B isoforms exhibited different tissue expression patterns and were developmentally regulated. Both isoforms are rapidly modulated toward upregulation during bacterial challenge in an isoform and/or tissue-dependent fashion. Conclusion: Both LEAP-2 isoforms play protective roles not only in embryonic and larval development but also in early immune response to bacterial invasion in mud loach. The regulation pattern of the two isoform genes under basal and stimulated conditions would be isoform-specific, suggestive of a certain degree of functional divergence between isoforms in innate immune system in this species.