원전 주변의 농경지에서 생산되는 농산물은 방사능 오염으로 인해 체내 방사능 오염을 유발할 가능성을 가질 수 있다. 이에 원전 주변에서 채취된 농산물을 건조 처리하여 섭취에 의한 내부피폭선량 평가를 위해 90Sr의 방사능 농도의 한계치를 알아보고자 하였다. 감마동위원소 분석결과 모든 시료에서 인공핵종은 검출 되지 않았으며, 쌀에서 < 0.0166~0.0336 Bq/kg-fresh, 배추에서 <0.00586~0.0421 Bq/kg-fresh, 열무에서 <0.013 5 ~0.106 Bq/kg-fresh, 배에서 0.0114 ~ 0.0901 Bq/kg-fresh 로서 평상변동범위 수준이었다. 일반인에 대한 연간 선량한도인 1.0 mSv 대비 쌀, 배추, 열무의 90Sr에 대해 각각 0.0177%, 0.0222%, 0.0376%, 0.00243%가 나 왔으며, 이 값은 일반인에 대한 법적 기준치 1 mSv/yr∙man 비해 0.1 % 미만의 값이 나타났다. 따라서 식생활에서 음식 섭취량 또는 연령을 고려하여 어린이, 어른이 섭취하는 식품에 대한 폭넓은 평가가 필요할 것으로 사료된다.

Purpose – This study aimed to investigate the effect of entrepreneurial temperament (ET) such as innovativeness, risk-taking, and proactiveness in entrepreneur’s lifetime before start-up and the effect of social capital (SC) such as network ties and trustworthiness on entrepreneurial intention. Research design, data, and methodology - We examined the components of ET (innovativeness, risk-taking, and proactiveness) and components of SC (network ties and trustworthiness) through existing prior research and investigated the factors that affected entrepreneurial intention. The first hypothesis of this study was that entrepreneurial temperament will have a significant impact on network ties of social capital, and the second hypothesis assumed that entrepreneurial temperament will have a significant effect on the trustworthiness of social capital. Finally, the second hypothesis assumed that social capital will have a significant impact on entrepreneurial intentions. We collected 175 data using questionnaires for people who have not yet started a start-up. And we used the Structure Equation Modeling (SEM) to evaluate the collected data and to test the research model by the two step research procedure. Results – As a result, the innovativeness and proactiveness of ET have a significant effect on network ties and trustworthiness of SC, but the effect of risk-taking on risk-taking of SC is not significant. On the other hand, network ties and network ties of SC was revealed a significant effect on the EI. Conclusions - The implications of this article could be observed as mentioned in this paper. First, we found that entrepreneurial innovativeness and proactiveness are helpful in constructing SCs, but not risk-taking. These results demonstrated that ET of entrepreneurs is important factor in the formation of social capital. Second, the SC that an entrepreneur built before the start-up has a meaning for EI. In conclusion, ET was affected partially to EI mediated SC. It is academic in that ET and SC are independent from each other and have a mediating role between ET and EI, unlike those directly affecting EI. Although some important implications were found in this study, this study had some limitations and we hope that future research will be complemented.

Purpose - The purpose of this study is to grasp the concept, characteristics and application status of sharing economy, and to derive a research model based on sharing economic service, and to analyze factors and influences of consumers' intention to reuse of sharing economy. Research design, data, and methodology - The questionnaires were created to examine variables for practical and theoretical implications. After pilot survey, conducted for 24 days from March 10th to April 2st in 2017, total numbers were 377. But 330 copies were used for the analysis with IBM SPSS Statistics 23.0 and IBM SPSS AMOS 23.0. The structural equation model was applied for this. Results - First, sharing economic services remain at an early stage, but it is meaningful to identify the revenue mechanism of the business model of the sharing economic platform. Second, in this study, it is meaningful that we systematized the theoretical structure by examining existing studies on the characteristics of the sharing economic service and consumer characteristics, and by examining empirically. Third, Satisfaction and Reliability are related to the characteristics of Sharing Economic Service (Security, Convenience, Discount, Sharing, Social Interaction), Consumer Characteristics (Personal Innovation, Word-of-Mouth) It is meaningful to broaden the understanding of the factors by verifying the mediating effect. Fourth, the sharing economy business is meaningful in that it is a new consumption trend that changes the meaning of consumption to consumers. Gradually, more and more people are recalling that purchasing something is not consumption, but sharing and borrowing is also consumption. In other words, through the sharing economy, consumers can experience more products and services, have more choices, and are expected to have a positive impact on economic growth by increasing the utilization of idle resources. Conclusions - Currently, the sharing economy is growing rapidly all over the world. Therefore, in the subsequent study, it is necessary to compare Korea and China's sharing economy and study the cultural and social characteristics of Korea and China. In particular, I think that steady research is necessary for more precise and specific direction on the influence of the shared economy.

Purpose - This study attempted to discover the impact of the Korea-China FTA(Free Trade Agreement) on electronic products distribution industry. Strategies will be provided to expand both countries' trade after the Korea-China FTA. Research design, data, and methodology - This study analyzed the differences before and after the Korea-China FTA, using an RCA(Revealed Comparative Advantage) index, TC(Technology Sophistication Index) index and TSI(Trade Specialization Index) that considered the FTA tariff situation. Data was collected from the International Trade Statistics Database and Korea, China Customs Service. Results - The results indicate that following the Korea-China FTA, China and Korea’s bilateral trade of electronic products is expected to expand, and both countries will experience net welfare gains from the markets’ expansion. Korea is competitive in several key products, although it faces competition from China. China's electronic products' competitiveness have indicated an increasing trend. Conclusions - The two countries should closely cooperate and communicate with each other. Ultimately, Korea should focus on high-tech, sophisticated techniques to gain market advantage. On the other hand, with the tariff decrease as well as the labor cost and labor force base, China will greatly be able to benefit from the manufacturing of medium- to low-end products in the future.

Gonadotropins are heterodimers consisting an alpha chain (Cgα) and a beta chain. Interestingly, presence of complicated LH-β transcripts in rat testis was accidently found; testicular LH-β transcripts were confined in seminiferous tubules to spermatids, and the translated products were localized in the elongated spermatids. We hypothesized that mouse testis has potential to produce the tissue specific LH-β with similar structure to the rat testicular forms. To verify our hypothesis, we examined the adult mouse (ICR) testis using RT-PCR and immunohistochemistry. The PCR revealed the presence of the identical products in the reactions for three LH subunit types. The expected product sizes for mouse Cgα and LH-β known as pituitary type were 224 bp and 503 bp, respectively. The testicular type LH-β products were produced by a primer set based on the rat sequences, with unexpected size of 800 bp. Sequencing revealed that the proximal and distal parts (2-82 and 661- 773 bp, respectively) were homologous to rat testicular LH-β cDNA, and middle part (83-660 bp) was a unique mouse-specific region. Both Cgα and LH-β positive signals were in the round and elongated spermatids and mature sperms, and the LH-β signals were more intense. In conclusion, our study demonstrated that the presence and localization of the LH subunits in mouse testis. Further studies will be needed to understand the precise structure and function of mouse testicular LH.

Direct communication between neighboring cells through connexin (Cx)-based gap junction is a crucial biolo– gical manner to regulate functions of a tissue consisting of multi-cell types. The present research evaluated expressional changes of Cx isoforms in the caput epididymis of adult rat exposed to estradiol benzoate (EB) or flutamide (Flu) at the early postnatal age. A single subcutaneous administration of EB at a low-dose [0.015 g /kg body weight (BW)] or a high-dose (1.5 g/kg BW) or Flu at a low-dose (500 g/kg BW) or a high-dose (5 mg/kg BW) was performed to an animal at 1 week of age. Quantitative real-time PCR analysis was employed to determine expressional changes of Cx isoforms. The transcript levels of Cxs30.3 and 37 were decreased by a low-dose EB treatment, while decreases of Cxs31, 31.1, 32, 40, and 45 transcript levels were observed with a low-dose EB treatment. The treatment of a high-dose EB resulted in expressional reduction of Cxs30.3, 31, 31.1, 37, 40, 43, and 45. The Flu treatment at a low dose caused increases of Cxs26, 37, and 40 transcript levels but decreases of Cxs31.1, 43, and 45 transcript levels. Increases of Cxs30.3, 31, 37, and 40 mRNA amounts were induced by a high-dose Flu treatment. However, exposure to a high-dose Flu produced expressional decreases of Cxs31.1, 32, and 43 in the adult caput epididymis. These observations suggest that exposure to EB or Flu at the neonatal period could lead to aberrant expression of Cx isoforms in the adult caput epididymis.

Surgical castration (also known as orchidectomy, ORX) has been frequently performed to avoid uncontrolled breeding. However, it has some serious disadvantages. Several laboratories have developed chemical castration methods, using bilateral intratesticular injection (BITI) of simple chemical solutions. The present study was undertaken to compare the effects of ORX and of hypertonic saline BITI on the androgen-sensitive tissues such as pituitary and hypothalamus. Serum testosterone (T) levels of ORX animals and hypertonic saline BITI animals (SAL) after 4 weeks of the manipulations exhibited significantly drops as compared with the levels of intact animals (Intact:ORX:SAL = 7.74± 1.31:1.34±0.19:1.28±0.18 ng/ml, p<0.001). Both ORX and BITI method induced similar stimulatory effects on the pituitary gonadotropin subunits and hypothalamic KiSS-1 gene expressions. In contrast, the effects of ORX and hypertonic saline BITI on hypothalamic GnRH gene expression were different from these gene expressions, shown an inverse relationship between the two groups (Intact:ORX:SAL = 1:0.45±0.06:1:2.07±0.41:1.51±0.37 AU; ORX, p<0.001; SAL, p< 0.05). In conclusion, we provided evidence that hypertonic saline BITI method has equivalent efficacy of T depletion to surgical castration in rats. The present study suggests the hypertonic saline BITI could be a promising substitute to conventional surgical castration.

An experiment was conducted to investigate the annual reproductive cycle of a Korean endemic species, Acheilognathus majusculus, from Jeokseong-myeon located in Seomjin River. The reproductive cycle is examined histologically regarding water temperature and day length of the habitat, the gonadosomatic index (GSI), the female ovipositor length index (OLI), monthly variation in egg diameter distribution, and developmental characteristics of female and male gonads. The maximum GSI was found in 19.21±2.32 and 6.90±0.53 for female and male respectively when water temperature (14℃) and day length (11.1hr) began to rise. On the other hand, the minimum level was reached during August (1.87±0.67 for female and 0.88±0.50 for male). No samples represent with measurable ovipositor between September and November, while the longest ovipositor length index was in April (79.68±4.69%). We compared and calculated the stages of testis and ovary development process in order to determine the germ cell development characteristics and the reproductive cycle. According to the result, we classified the female Acheilognathus majusculus reproductive cycle into four stages: Ripe (April) and spawning phase (May to June), degenerative phase (July), growing phase (August to December), and mature phase (January to March). The annual reproductive cycle of male Acheilognathus majusculus was categorized into five stages viz. Ripe and spawning phase (May to June), degenerative phase (July to August), resting phase (September to November), growing phase (December to February), and mature phase (March to April).

The paper examines critical factors affecting consumer behavioral intentions in accepting online health communication through social networking sites. Unlike recent research under this topic, the paper assimilates some components of service quality dimensions and consumer behavior theories. The paper employs factor analysis and structural equation modelling analysis with latent variables to identify critical factors from the survey data collected from Korean consumers. The results of the study identifies three major constructs: consumer needs for health information, the perceived value of tangible attributes of health information providers, and the perceived value of intangible attributes of health information providers. The results show that consumer needs for health information and the tangible and intangible attributes of health information providers should be considered as important antecedents of accepting online health communication through social networking sites. The findings suggest that the success of online health communication via social networking sites largely depends on the tangible and intangible attributes of health information providers.

In order to examine the effects of four different light spectra (i.e., white, red, green, blue) on the oocyte maturation in grass puffer, the change of reproductive parameters via brain-pituitary-gonad (BPG) axis were investigated in this study. After exposure to four different light spectra for 7 weeks, the abundance of gonadotropin-releasing hormone (GnRH) mRNA which is a type of seabream (sbGnRH) and two different of subunit of gonadotropin hormones mRNAs, follicle-stimulating hormone (fshβ) mRNA and luteinizing hormone (lhβ) mRNA, were analyzed in the brain and pituitary. Gonadosomatic index (GSI) and oocyte developmental stage were also investigated in the gonad based on anatomical- and histological observations. GSI value was significantly increased in the green spectrum-exposed group when compared to that of the other light-exposed groups (i.e., white, red, blue), with the presence of yolk stage oocytes (p˂0.05). The abundances of sbGnRHmRNA and fshβ mRNA in the green spectrum-exposed group were also significant higher than those of the other light spectra-exposed groups(p˂0.05). However, there was no significant difference between the abundances of lhβmRNA in all light spectra-exposed groups. These results indicate that the maturation of oocyte in grass puffercan be accelerated by exposure to the spectrum of green. The sbGnRHmRNA and fshβ mRNA may play an important reproductive parameters role in the initiation of maturation of oocyte. To better understand the molecular mechanism for the maturation of oocytein grass puffer, further study examining the relationship between oocyte development and its related genes (e.g., sbGnRHmRNA and fshβmRNA) is required.

This study carried out to examine the association between the haplotypes of mitochondrial control region (CR) and growth traits of two F1 progeny populations of the Red-spotted grouper. We found polymorphic patterns of the 133-bp repeat units in the CR. In the BBR01 population (70-days after hatching), a total of 1,091 F1 progeny were divided into three haplotypes (H01, H03 and H04). The significant differences were found in the levels of BL, BW and LWI (p<0.05). The F1 animals with the haplotype H01 had greater level of BL (50.815±4.586 mm) than those of H03 (47.270±6.486 mm) and H04 (47.179±6.278 mm). The H01 F1 fishes were heavier level of BW (2.270±0.559 g) than those of H03 (1.789±0.711 g) and H04 (1.797±0.706 g). In the BBR02 population (11-months after fertilization), three haplotypes H03, H04 and H05 were detected. The significant difference was found only in the BL values among three haplotypes (p<0.05). The F1 animals with the haplotype H03 had greater level of BL (19.22±2.000 cm) than those of H04 (18.64±1.964 cm) and H05 (18.86±1.512 cm). There were no significant differences in BW and LWI among haplotypes in the BBR02 population (p>0.05). These results suggested that the mitochondrial haplotypes may affect the growth traits during early developmental stage of the Red-spotted grouper. The marker-assisted selection system for broodstock animals may be helpful in improving performance traits for aquaculture of the Red-spotted grouper.

In fish, light (photoperiod, intensity and spectra) is main regulator in many physiological actions including body growth. The present study was to investigate the effect of light spectra on the body growth in red spotted grouper Epinephelus akaara. Experiment performed from December, 2016 to March, 2017 and fish (n=200, body weight 6.9±0.1, total length 7.5±0.1) was reared under different light spectra (blue, green, red and white) for 15 week under 12 hour light and 12 hour dark photoperiod and natural water temperature (13.6~16.7℃). We examined the mRNA expression levels of growth hormone (GH) in the brain with pituitary and photoreceptors mRNA expression in the retina. Red spotted grouper of BW was no different in each for the four groups (light spectra of blue, green, red and white) to five week of rearing period, but BW of rearing blue light spectra group fish was significantly increased in ten week of rearing period. After that, in 15week of rearing period, BW of four group fish was no showed difference respectively. The total length (TL) of fish was no differed in four experimental groups under the experimental duration respectively. The gh mRNA was more highly expressed in rearing blue light spectra group fish than other experimental groups in 15 weeks. The short wavelength sensitive opsin (sws) mRNA was more increased in rearing blue light spectra group fish than other groups in 15 weeks. The middle wavelength sensitive opsin (mws) and rod opsin mRNA expression was no differed in four experimental groups under all experimental durations respectively. The long wavelength sensitive opsin (lws) mRNA expression was more increased in rearing red light spectra group fish than other groups in 15 weeks. Our present results suggest that somatic growth of red spotted grouper is induced under blue light condition under low water temperature duration. Also, these results are thought to be affected of the gh and sws mRNA expression blue wavelength. However, in this experiment we did not confirm the correlation between GH and photoreceptor. Therefore, further studies are needed to clarify the correlation of the light spectra and photoreceptor with body growth in red spotted grouper.

Nonylphenols (NP) are used in manufacturing antioxidants and lubricating oil additives, which are considered to be as potent endocrine disruptor. The aim of this study was to examine the effects of NP on reproductive system in adult male mice. Mice were divided into 4 groups; (1) tap water (CON group), (2) 50 μg/L (NP50), (3) 500 μg/L (NP500) and (4) 5000 μg/L (NP5000) of NP via the drinking water for 4 weeks. Mice were sacrificed and the reproductive organ weights were measured. The caudal epididymal sperms were count to assess the toxicity on germ cells. Histopathological changes of tissues were observed by using hematoxylin/eosin staining. The weights of testis in NP5000 group were significantly lighter than those in CON group (104.9±2.9 mg vs 90.7±5.1 mg, p<0.05). And weights of epididymis significantly increased in NP500 group (44.2±2.6 mg vs 54.42±3.44 mg, p<0.05). As concentration of NP increased, the number of sperms significantly decreased (NP50 and NP500, p<0.01; NP5000, p<0.001). In histopathological analyses, the sperms in seminiferous tubules showed a concentration-dependent decrease in mice treated with NP. In epididymis, treatment with NP resulted in empty space and the reduced sperm numbers in dose-dependent manner. Our results confirmed the dose-dependent decrease in the number of sperm and histopathological abnormality of testis and epididymis in mice exposed from 50 μg/L to 5000 μg/L of NP for 4 weeks. The present study suggests that oral exposure of NP might have negative effects on reproductive function, particularly on germ cells, in adult male mice.

Nonylphenol (NP) is known to be an endocrine disruptor with estrogen-like activity. In this study, we tested low dose of NP and its alternative candidate Octyl-β-D-glucopyranoside (OG) on F1 female mice (n=10) from parents (P) generation to postnatal days(PND) 56. Animals [Control (tap water), NP-50 (50ug/L, drinking water), OG-50(50ug/L, drinking water)] were fed with normal chow and drinking water. ad libitum. Body weights and tissue weights were measured after sacrifice, and sera were measured using creatinine assay (n=8) and blood urea nitrogen (BUN) ELISA kit (n=8). Histopathology of kidney was used Hematoxylin & Eosin staining method and Periodic Acid-Schiff(PAS) staining method. NP treatment significantly increased body weight and kidney weight of F1 female(p<0.05). The serum levels of creatinine in NP-50 and OG-50 significantly decreased(p<0.001 and p<0.01, respectively) compared to the control group. In histopathological study, renal tubules spaces were increased and severe glomerular anomalies were found in NP-50 and OG-50. In NP-50, the thickened basal membrane was observed. The present study demonstrated that NP and OG has renal toxicity, and this toxicity due to long-term low dose treatment seems to be occurred in the next generation and female-specific.

Background & Objectives: Methoxychlor(MET), an organochlorine insecticide, has been thought a potent endocrine disrupting chemical. The present study was undertaken to examine whether short-term exposure to MET can alter the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in prepubertal female rats. Method: MET (1, 10 and 100 mg/kg/day) was administered daily from postnatal day 25 (PND 25) through the PND 34, and the animals were sacrificed on the PND 35. The first V.O. day was monitored, and the weights of reproductive tissues were measured. To assess the structural alterations in the ovary and uterus, the tissues were embedded in paraffin and stained for histological analysis. The transcriptional activities of hypothalamic and pituitary genes were measured using quantitative RT-PCRs. The uterine and hypothalamic proteins were extracted and used for the ER western blotting. Results: As a result, 100 mg group showed advanced V.O. than control, 1 mg group and 10 mg group. The wet weights of ovaries from MET-treated animal dose-dependently increased. The uterine weights were increased in 1 mg group and 10 mg group, while the 100 mg group samples were not significantly different from control tissues. The adrenal, kidney, spleen and thymus weights were not shown any significant change. Corpora lutea and fully grown follicles were observed in the ovaries from the 100 mg group, while numerous primary and secondary follicles were observed in the ovaries from control group. Myometrial thickness of MET-treated group was dose-dependently increased. Epithelial hypertrophy and well-developed glands were observed in the uterus from the 10 mg groups. Conclusions: The present study demonstrated that the short-term exposure to MET during the critical period of prepubertal stage could activate a reproductive endocrine system, resulting the early onset of puberty in immature female rats. Our study suggests that MET’s disrupting effect might be derived from premature activation of key reproduction-related genes in hypothalamus-pituitary neuroendocrine circuit.

Background & Objectives : Nonylphenol (NP), a member of alkylphenols, has been widely used in manufacturing antioxidants, The present study was undertaken to examine whether short-term exposure to NP can alter the onset of puberty and associated reproductive parameters such as hormone receptor expressions in prepubertal female rats. Methods : NP (0.1, 1, 10 mg/kg BW) was administered orally at 10:00 from postnatal day 25 (PND 25) through the PND 35. The control group was administered orally each day 200 uL of the sesame oil. At PND 36, all groups were sacrificed at 18:00. The first vaginal opening (V.O.) day was monitored, and the weights of reproductive tissues were measured. Ovaries and uteri were used for analysis of mRNA levels, protein levels and histology. The transcriptional activities of the ovaries (StAR, P405scc, 3β-HSD, 17β-HSD, Aromatase and LH-R) and uteri(ER) were measured using quantitative RT-PCRs. The uterine proteins were used for the ER western blotting. Histological analysis of the reproductive organs was carried out. Results: Administration of NP induced early V.O. when compared to control. The ovarian weights of 1 mg group (0.164±0.010 mg/g BW) was significantly higher than those of control group (0.116±0.007 mg/g BW). Among the steroidogenesis-related genes, mRNA levels of the ovarian P450scc, 3β-HSD and Aromatase are increased significantly in all NP-treated groups. The mRNA levels of StAR and 17β- HSD were unchanged. NP administration (1 mg group) significantly increased the LH-R transcript level. Among the steroid hormone receptor genes, the mRNA level of ER-alpha was significantly elevated in 1mg NP group, while the mRNA levels of ER-beta and PR were unchanged in all NP-treated groups. Interestingly, wetern blotting data for uterine steroid hormone receptors revealed the complete disagreement with the transcriptional activities. Histological status of ovaries and uteri also exerted the occureence of advanced maturation in NP-treated groups. Conclusion: The present study demonstartes that the short-term administration of NP accelerates V.O. and maturation of reproductive organs such as ovary and uterus.

Due to modern trends with postponing child-bearing and getting worse living environment in women, an ovarian aging increased pregnancy failure and other complications with menopause or premature ovarian failure. Although several theories have been suggested such as mitochondrial malfunction, DNA damage/repair/methylation, caloric restriction, studies regarding ovarian aging-related molecular mechanisms for development of therapeutic methods are insufficient so far. Our objective is to determine molecular pathways of ovarian aging that result in pregnancy failure and other complications in women health to develop treatment strategies. This study is consisted of two parts: in Phase I stage, we analyzed distinct gene expression profile between young and aged mouse ovaries, and in Phase II stage several preferentially expressed genes in both ovaries were selected and analyzed their physiological functions and involved molecular networks related to ovarian aging for development of diagnostic markers and therapeutic methods. Ovaries from 10 week and 11 month-old FVB/NJ female mice with synchronized estrus cycle were collected for this study. A half of each ovary was used for RNA preparation and the other half for histological analysis. Using the Illumina HiSeq 2000 System, preferentially expressed genes were identified. Functional annotation database-based gene-set enrichment analyses and Pathway Studio® were employed to evaluate aging-related molecular networks. These findings were confirmed through qRT-PCR and immunohistochemistry. To validate RNA-Seq data, we examined expression patterns of marker genes (Amh, Bmp15 and Nobox) that were wellknown to be decreased in ovarian aging process. In young or aged ovary, preferentially expressed 876 genes were identified and extracellular matrix (ECM; p<0.001) and chromatin/nucleosome-related (p<0.001) protein-coded genes have the majority in these genes by GOTERM analysis. Amongthem, we selected several candidate genes and confirmed their expression profiles by qRT-PCR and immunohistochemistry followed by molecular network analysis. Regarding molecular interactions in these genes, PathwayStudio® was employed to predict aging-involved molecular networks in mouse ovary. Here we report a couple of candidate molecular networks and medicines (chemicals) for targeting these preferentially expressed genes/proteins. Further analyses are scheduled to produce transgenic animal models and with human ovarian tissues/cell lines.

The conserved The oocytes acquire competence to undergo complex processes, oocyte growth and oocyte maturation, and the capacity for fertilization and preimplantational embryo development, by accumulating RNAs and proteins in the ooplasm. Therefore, the identification of the genes expressed in the oocyte and its functional analysis will provide valuable resources to study molecular regulatory mechanism of oocyte maturation, fertilization and early embryogenesis. To better understand these mechanisms, a decade ago, we identified a list of differentially expressed genes between GV and MII oocytes using annealing control primer (ACP)-PCR technology. Among these genes, we selected two genes, Gas6 (growth arrest-specific 6), and Sebox (skin-embryobrain- oocyte homeobox) that expressed significantly higher levels in GV than MII and analyzed its functions by using RNA interference (RNAi). Unexpectedly, and fortunately, it turned out that both of genes are new candidate of maternal effect genes (MEGs) that is important for fertilization and/or early embryogenesis but not crucial for oocyte meiotic maturation. In particular, Gas6 is essential in maintaining the proper mitochondrial function, and biosynthesis of heparan sulfate and glutathione, which are required for normal sperm chromatin decondensation, pronuclear formation, and mainly for the sufficient cytoplasmic maturation of oocytes. We suggest that the correction in the Gas6 signaling network in oocytes may improve the embryonic developmental capacity caused by deterioration of the mitochondrial functions and/or contents during oocyte maturation. Meanwhile, Sebox is crucial for zygotic genome activation (ZGA) required for subsequent embryonic development beyond the 2-cell stage by coordinating the expression of other maternal factors, such as c-mos, Gdf9, Ube2a and Wee1. In conclusion, the observed failure of fertilization after Gas6 RNAi and the embryonic development at the 2-cell stage after Sebox RNAi was similar to the loss-of-function of the previously well-known MEGs. Based on these findings, we added Gas6 and Sebox as new mammalian MEGs. Findings of our research would broaden our knowledge regarding MEGs and a field of maternal programming in oocytes.

This study analyzed the mitochondrial DNA (mtDNA) sequences of the Red-spotted grouper, Epinephelus akaara (Perciformes, Serranidae), and used for construction of molecular phylogeny and for association between maternal haplotypes and phenotypic differences of F1 progeny. This study revealed phylogenetic position of the endangered red-spotted grouper, Epinephelus akaara (Perciformes, Serranidae) based on the nucleotide sequences of complete mt genome. Complete nucleotide sequences were determined from the mt genomes of two individuals of the red-spotted grouper caught in South Korea. The mitochondrial genome had 16,795 base pairs (bp) and 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a noncoding control region. The two mt genomes were highly homologous (99.71% similarity). The two mt genomes of E. akaara determined in this study were found in Clade I in the phylogenetic tree with those of E. awoara, E. fasciatomaculosus, E. sexfasciatus, E. diacanthus, E. sticus, and E. morio, suggesting that this may be helpful to understand phylogenetic position of Epinephelus species including red-spotted grouper. The genetic structure and phylogenetic relationship were investigated in the red-spotted grouper populations using the sequence polymorphisms of the cytochrome c oxidase subunit I(COI) gene and variable number of tandem repeats (VNTRs) of the control region (CR). A total of forty-one COIhaplotypes were found from 174 COIsequences from East Asia. The Jeju Island population (n=5) had four haplotypes, and the South Sea population (n=105) had twenty-five haplotypes. The Hong Kong population had nineteen haplotypes from fifty-nine COIsequences determined in this study. Among the COIhaplotypes, EAC_03 is commonly found in all populations (Jeju Island and South Sea of Korea, China, Hong Kong and Taiwan). In addition, there were four haplotypes (EAC_12, EAC_14, EAC_28 and EAC_35) also common among the populations tested in this study and collected from NCBI database. However, twenty haplotypes were specific in the Korean populations, and fifteen haplotypes were specific in the China and Hong Kong populations. The neighbor-joining (NJ) trees constructed from the phylogenetic analyses based on the polymorphisms of the COIhaplotypes showed the monophyletic branching pattern within the genus Epinephelus, indicating that the red spotted grouper populations had evolved from common maternal ancestors. Consequently, East Asian red-spotted grouper populations are maternally related at least in part, as well as sharing the same evolutionary history, and still affected by the East Asian ocean current (Kuroshio). From the haplotype analysis for mtDNA CR, we obtained VNTR polymor-phisms in all populations tested. We found five haplotypes for the CR VNTR patterns. The 133-bp repeat units were counted two to five. Using CR VNTR haplotypes, the statistical association was examined between mtDNA haplotypes and growth traits of aquafarming young fishes of the red-spotted grouper. A total of 386 F1 progeny, which were randomly selected from a progeny population produced by artificial insemination in the farm, were genotyped and statistically compared their body length (BL), body weights (BW) and length-weight indexes (LWI) at 11-months after hatching. There haplotypes H03, H04 and H05 were detected for CR in the parents and progeny populations. The significant difference was found in the BL values among three haplotypes (p<0.05). The F1 animals with haplotype H03 had freater level of BL (19.22±2.000 cm) than those of H04 (18.64±1.964 cm) and H05 (18.86±1.512 cm). There were no significant differences in BW and LWI among haplotypes (p<0.05). These results concluded that the maternal lineages affected the growth rates during early developmental stage in the red-spotted grouper. These findings suggested that the mitochondrial background of the fertilized eggs may play an important role in the early development, and the markerassisted selection system for broodstork animals may be helpful in improving performance traits for aquaculture industry as well as for conservation biology of the endangered red-spotted grouper. However, the results from the association analysis between haplotypes and phenotypes of F1 progeny (n=1,093) at 60-days after hatching showed that there were no significant difference (p>0.05). Consequently, the results of this study may be useful information for understanding the evolutionary relation with other species and may be good genetic markers for breeding management in the red-spotted grouper aquaculture system.

Peroxiredoxin1 (Prdx1) is an antioxidant enzyme belonging to the peroxiredoxin family of proteins. Prdx1 catalyzes the reduction of H2O2 and alkyl hydroperoxide and plays an important role in different biological processes. Prdx1 also participates in various age-related diseases and cancers. In this study, we investigated the role of Prdx1 in pronephros development during embryogenesis. Prdx1 knockdown markedly inhibited proximal tubule formation in the pronephros and significantly increased the cellular levels of reactive oxygen species (ROS), which impaired primary cilia formation. Additionally, treatment with ROS (H2O2) severely disrupted proximal tubule formation, whereas Prdx1 overexpression reversed the ROS-mediated inhibition in proximal tubule formation. Epistatic analysis revealed that Prdx1 has a crucial role in retinoic acid and Wnt signaling pathways during pronephrogenesis. In conclusion, Prdx1 facilitates proximal tubule formation during pronephrogenesis by regulating ROS levels.