• Journal of Life Science
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• v.25 no.12
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• pp.1347-1353
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• 2015

The fleshy shrimp, Fenneropenaeus chinensis, is the family of Penaeidae and one of the most economically important marine culture species in Korea. However, its genetic characteristics have never been studied. In this study, a total of 240 wild F. chinensis individuals were collected from four locations as follows: Narodo (NRD, n = 60), Beopseongpo (BSP, n = 60), Chaesukpo (CSP, n = 60), and Cheonsuman (CSM, n = 60). Genetic variability and the relationships among four wild F. chinensis populations were analyzed using 13 newly developed microsatellite loci. Relatively high levels of genetic variability (mean allelic richness = 16.87; mean heterozygosity = 0.845) were found among localities. Among the 52 population loci, 13 showed significant deviation from the Hardy–Weinberg equilibrium. Neighbor-joining, principal coordinate, and molecular variance analyses revealed the presence of three subpopulations (NRD, CSM, BSP and CSP), which was consistent with clustering based on genetic distance. The mean observed heterozygosity values of the NRD, CSM, BSP, and CSP populations were 0.724, 0.821, 0.814, and 0.785 over all loci, respectively. These genetic variability and differentiation results of the four wild populations can be applied for future genetic improvement using selective breeding and to design suitable management guidelines for Korean F. chinensis culture.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.1
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• pp.31-37
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• 2019

Objective: At least eight local duck breeds have been recognized and documented as national germplasm of Indonesia so far. It is necessary to genetically characterize the local duck breeds for aiding conservation and future improvement strategies. Thus, this study was carried out to assess genetic diversity and phylogenetic relationship of eight local duck populations of Indonesia using microsatellite markers. Methods: In total, 240 individuals (30 individuals each population) from Alabio (AL), Bayang (BY), Magelang (MG), Mojosari (MJ), Pegagan (PG), Pitalah (PT), Rambon (RM), and Turi (TR) duck populations were genotyped using 22 microsatellite markers. Results: The results showed a moderate level of genetic diversity among populations, with a total of 153 alleles detected over all loci and populations, ranging from 3 to 22 alleles per locus. Observed (Ho) and expected heterozygosity (He), as well as polymorphism information content over all loci and populations were 0.440, 0.566, and 0.513, respectively. Heterozygote deficiency in the overall populations ($F_{IT}=0.237$), was partly due to the heterozygote deficiency within populations ($F_{IS}=0.114$) and moderate level of genetic differentiation among populations ($F_{ST}=0.137$). The most diverse population was MG (He = 0.545) and the least diverse population was AL (He = 0.368). The majority of populations were relatively in heterozygote deficiency (except AL), due to inbreeding. The genetic distances, phylogenetic trees, and principal coordinates analysis concluded that the populations can be grouped into two major clusters, resulting AL, MG, and MJ in one cluster separated from the remaining populations. Conclusion: The present study revealed a considerable genetic diversity of studied populations and thus, proper management strategies should be applied to preserve genetic diversity and prevent loss of alleles.

• Animal Bioscience
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• v.34 no.7
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• pp.1123-1133
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• 2021

Objective: Shandong indigenous pig breeds are important Chinese pig resources. Their progressive population decline in recent decades has attracted attention towards their conservation. Conservation genetics of these indigenous breeds are essential for developing a conservation and utilization scheme. Methods: A high-density single nucleotide polymorphism (HD-SNP) chip-based comparative analysis of genetic characteristics was performed for seven Shandong indigenous pig breeds in the context of five Western commercial breeds. Results: The results showed that Shandong indigenous pig breeds varied greatly in genetic diversity, effective population size, inbreeding level, and genetic distance with the Western commercial breeds. Specifically, Laiwu and Dapulian displayed low genetic diversity, and had a genetically distant relationship with the Western commercial breeds (average F statistics [F_ST] value of 0.3226 and 0.2666, respectively). Contrastingly, the other five breeds (Yantai, Licha, Yimeng, Wulain, and Heigai) displayed high genetic diversity within breed and had some extent of mixture pattern with the Western commercial breeds, especially Duroc and Landrace (F_ST values from 0.1043 to 0.2536). Furthermore, intensive gene flow was discovered among the seven Shandong indigenous breeds, particularly Wulian, Licha, and Heigai, as indicated by the large cluster formed in the principal component analysis scatterplot and small population differentiation (average of 0.1253) among them. Conclusion: Our study advances the understanding of genetic characteristics of Shandong indigenous breeds and provides essential information for developing an appropriate conservation and utilization scheme for these breeds.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.64-64
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• 2003

The sex differentiation of fishes occurs under the control of genetic and various environmental factors. DM-domain containing genes are novel zinc finger transcription factors and play key roles in sex determination. In order to isolate the wrasse DMRT (wDMRT) cDNA from the protogynous wrasse (Halichoeres tenuispinnis), the wrasse testis cDNA library was screened using the $^{32}$ P-labeled PCR products, which were amplified with the degenerate primers from conserved DM-domain regions of several DMRT genes. Among a few positives obtained through screening, the full length wDMRT cDNA of 2.9kb size encoding a predicted 300 amino acid residues was isolated. The sequence analysis exhibited 60%, 43% sequence identity with rainbow trout and tilapia DMRT1, respectively. RT-PCR assay showed that wDMRT was expressed specifically in male testis. Also, wDMRT gene was strongly expressed in May during reproductive season, when the reproductivity of wrasse is most active. This results suggested that wDMRT gene function in testis differentiation The conserved DM-domain regions were amplified using PCR from DMRT genes of several species among Labridae, and their sequences were determined. The sequence of DM-domain region of Halichoeres. tenuispinis was identical to those of Pseudolabrus japonicus, Pteragogus flagellifera, and showed 94% identity with that of Halichoeres poecioptrerus.

• Journal of Embryo Transfer
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• v.20 no.1
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• pp.35-41
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• 2005

This study was carried out for development of effective preservation on animal genetic resources. Spermatogonia cells are the germline stem cells and they can be restored to adult animal with proliferation and differentiation intentionally. When the spermatogonia cells were purified from seminiferous tubules and were cultured at $32^{\circ}C$, the cells were actively proliferated. The culture medium consisted of TCM199 plus $10\%$ FCS and coculture with Sertoli cells supported cultivation of spermatogonia cells. By passing 40 days of incubation, spermatogonia cells formed the germline colony or shape of ES-like colony or reconstruction of pseudo-seminifcrous tubule shape. At 40 days, the cultured cells were no sign for differentiation to spermatocyte or spermatid. The experiment of induced differentiation of this cells is needed.

• Development and Reproduction
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• v.17 no.1
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• pp.9-16
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• 2013

Coactivator-associated arginine methyltransferase 1 (CARM1) is included in the protein arginine methyltransferase (PRMT) family, which methylates histone arginine residues through posttranslational modification. It has been proposed that CARM1 may up-regulate the expression of pluripotency-related genes through the alteration of the chromatin structure. Mouse embryonic stem cells (mESCs) are pluripotent and have the ability to self-renew. The cells are mainly used to study the genetic function of novel genes, because the cells facilitate the transmission of the manipulated genes into target mice. Since the up-regulated methylation levels of histone arginine residue lead to the maintenance of pluripotency in embryos and stem cells, it may be suggested that CARM1 overexpressing mESCs elevate the expression of pluripotency-related genes in reconstituted embryos for transgenic mice and may resist the differentiation into trophectoderm (TE). We constructed a fusion protein by connecting CARM1 and 7X-arginine (R7). As a cell-penetrating peptide (CPP), can translocate CARM1 protein into mESCs. CPP-CARM1 protein was detected in the nuclei of the mESCs after a treatment of 24 hours. Accordingly, the expression of pluripotency-related genes was up-regulated in CPP-CARM1-treated mESCs. In addition, CPP-CARM1-treated mESC-derived embryoid bodies (EBs) showed an elevated expression of pluripotency-related genes and delayed spontaneous differentiation. This result suggests that the treatment of recombinant CPP-CARM1 protein elevates the expression of pluripotency-related genes of mESCs by epigenetic modification, and this protein-delivery system could be used to modify embryonic fate in reconstituted embryos with mESCs.

• Plant Biotechnology Reports
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• v.3 no.4
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• pp.333-340
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• 2009

Developmental anomalies in the plumule meristem of peanut (Arachis hypogaea L.) somatic embryos resulted in poor shoot differentiation and reduced plant recovery. Existing meristems with caulogenic potential have never been tested for embryogenesis in peanut. The present experiment was designed to test the mature zygotic embryo axis derived plumule with three meristems for somatic embryogenesis. Embryogenic masses and embryos developed from the caulogenic meristems in the axils. Exposure of 2 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation temporarily which then regained the ability to form the shoot on withdrawal of 2,4-D. Exposure of 4 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation irreversibly. No shoot formation was noted from the tips in any of the cultures which were in secondary medium with $13.6{\mu}M$ 2,4-D. Development of somatic embryos directly from axillary meristems was confirmed histologically. Conversion frequency of these embryos was 11%. Thus, in this report, we describe a method to obtain somatic embryos from the determined organogenic buds of the axillary meristem, by culturing the nodal explant vertically on embryo induction medium. It also displays the possibility of obtaining both embryogenic and organogenic potential in two parts of the same explant simultaneously. The possibility of extending this approach for genetic transformation in in vivo system through direct DNA delivery or Agrobacterium injection in meristems can also be explored. Using Agrobacterium rhizogenes, we have demonstrated the possibility of gene transfer in the axillary meristems of seed-derived plumule explant.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.369-376
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• 2005

Turnip mosaic virus (TuMV) is an infectious viral pathogen on the cruciferous crops, predominantly Chinese cabbage (Brassica campestris subsp. pekinensis) and radish (Raphanus sativus). On the basis of the symptom development in selective differential hosts from indicator host species, Chinese cabbage and Korean radish inbred lines, the representative eight isolates of TuMV were divided into two major groups/or six types. Group I includes Th 1, Ca-ad7, and Cj-ca2-1 isolates, while group II includes the other isolates (rg-pfl, r 9-10, Rhcql-2, Stock and Mustard). According to the molecular phylogenetic analysis, these isolates, however, divided into two groups and two independent isolates. Phylogenetic analysis indicated that four isolates (Tu 1, r9-10, Stock and Rh-cql-2) formed a distinct phylogenetic group, and the other two isolates (Ca-ad7 and Cj-ca2-1) also formed another group. Mustard and rg-pfl isolates did not seem to have any relationship with these two groups. Taken together, these results indicated that virulence differentiation on host plants, molecular phylogenetic analysis of the nucleotide and the deduced amino acid of TuMV coat proteins did not show any relationship. The multi-resistant lines, Wonyae 20026 and BP058 in Chinese cabbage represent valuable genetic materials that can be used for crucifer breeding programs on TuMV resistance, but not in Korean radish.

• BMB Reports
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• v.54 no.10
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• pp.505-515
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• 2021

Human pluripotent stem cells (hPSCs) include human embryonic stem cells (hESCs) derived from blastocysts and human induced pluripotent stem cells (hiPSCs) generated from somatic cell reprogramming. Due to their self-renewal ability and pluripotent differentiation potential, hPSCs serve as an excellent experimental platform for human development, disease modeling, drug screening, and cell therapy. Traditionally, hPSCs were considered to form a homogenous population. However, recent advances in single cell technologies revealed a high degree of variability between individual cells within a hPSC population. Different types of heterogeneity can arise by genetic and epigenetic abnormalities associated with long-term in vitro culture and somatic cell reprogramming. These variations initially appear in a rare population of cells. However, some cancer-related variations can confer growth advantages to the affected cells and alter cellular phenotypes, which raises significant concerns in hPSC applications. In contrast, other types of heterogeneity are related to intrinsic features of hPSCs such as asynchronous cell cycle and spatial asymmetry in cell adhesion. A growing body of evidence suggests that hPSCs exploit the intrinsic heterogeneity to produce multiple lineages during differentiation. This idea offers a new concept of pluripotency with single cell heterogeneity as an integral element. Collectively, single cell heterogeneity is Janus-faced in hPSC function and application. Harmful heterogeneity has to be minimized by improving culture conditions and screening methods. However, other heterogeneity that is integral for pluripotency can be utilized to control hPSC proliferation and differentiation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.1
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• pp.114-122
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• 1995

Defining the mechanisms of B cell diversification which establish the immune repertoire is fundamental to understand how the immune response is regulated. In this report, B cell differentiation and diversification focused on the regulation of immunoglobulin $V_H$ gene expression during ontogeny were analyzed by in situ hybridization technique. Fetal liver B cells in .different gestational days from 16d to 20d showed the predominant expression of $V_H7183$ and $V_HQ52$ without transition of repertoire during the observed gestation days. The two subsets of fetal liver B cells separated according to different differentiation stages based on the presence of tell surface immunoglobulin also did not indicate apparent difference in expressed $V_H$ gene family profiles. B cells in fetal spleen as an another hematopoietic lymphoid tissue in fetus also expressed similar $V_H$ gene repertoire to that in fetal liver B cells. This distinct pattern of $V_H$ gene expression in fetal B cells from that of adult B cells were not changed even after four weeks contact with adult bone marrow microenvironment supplied by the established adult bone marrow stromal cell layers. Thus, the restricted $V_H$ gene repertoire of B cells in fetus which is distinct from that in adult appears to be associated more with the genetic potential of fetal B cell progenitors and less with environmental influences or differentiation stages or compartmentalization.