• 한국수산과학회지
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• 제47권6호
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• pp.882-887
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• 2014

We studied oocyte steroidogenesis in blacktip grouper Epinephelus fasciatus ovarian follicles during vitellogenesis. Vitellogenic oocytes with average diameters of 0.45, 0.48 and 0.50 mm were incubated in vitro in the presence of $[^3H]17{\alpha}$-hydroxyprogesterone as a precursor. The steroid metabolites were analyzed using thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC/MS). The major metabolites in the vitellogenic oocytes were androstenedione ($A_4$), testosterone (T), estradiol-$17{\beta}$ ($E_2$), and estrone ($E_1$). The metabolites of androgen ($A_4$ and T) were higher in the 0.50-mm oocytes than in the 0.45- and 0.48-mm oocytes, while the estrogen metabolites (E2 and E1) were lower in the 0.50-mm oocytes. These results suggest that 0.50-mm oocytes are fully vitellogenic following initiation of the maturation process.

• 수산해양기술연구
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• 제35권4호
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• pp.391-396
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• 1999

It is well known that fish hear a wide frequency range of sound using both laterial line and inner ear, and the sound is probably the most effective channel for long-range communication underwater than any other stimulus.The auditory threshold of svenband grouper, Epinephelus septem fasciatus was determined by conditioning method using a sound coupled with electric shock in a tank. The audio-signals and electric shock used in the experiment were pure tones of 100 to 1000Hz and DC 6n.The response of fish to the sound was observed by ECG intervals from precordial leads method (V1·V2 method). The auditory threshold curve for sevenband grouper was V-shaped, with most sensitive threshold at 350Hz in the range of 100~1000Hz. The Sevenband grouper were more sensitive to sounds of 200~400Hz than to adjacent frequencies.

• Fisheries and Aquatic Sciences
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• 제26권6호
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• pp.380-392
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• 2023

Groupers (Family Epinephelidae) are commonly caught in data-poor small-scale multi-species fisheries for sale on both export and domestic markets. This study presents data on the species composition and size/life-stage structure of Epinephelus spp. groupers caught by small-scale fishers and sold locally in the Indonesian province of South Sulawesi. Data were collected from fishing ports and local markets at 12 sites representing the three seaways around South Sulawesi (Makassar Strait, Flores Sea, Gulf of Bone). Each specimen (n = 3,398) was photographed alongside an object of known length, and total length (TL) was obtained using the Rapid Scaling on Object (RASIO). Of the 23 species identified, four (Epinephelus areolatus, Epinephelus ongus, Epinephelus quoyanus, and Epinephelus fasciatus) collectively comprised 69% of the catch, while the 13 least abundant species contributed less than 5%. The catch was dominated (67%) by the subadult life-stage, with just under 20% in the adult class. Juveniles dominated the catch of Epinephelus fuscoguttatus, a valuable export commodity. Observations of early maturity as well as the sizeable gap between length at first capture (Lc) and length at first maturity (Lm) indicate recruitment overfishing of most species, with the notable exception of Epinephelus rivulatus. The proportion of adult fish was low (≈5%-30%) for the twelve most abundant species (E. areolatus, E. ongus, Epinephelus quoyanus, E. fasciatus, Epinephelus coioides, Epinephelus faveatus, Epinephelus sexfasciatus, Epinephelus maculatus, Epinephelus bleekeri, Epinephelus corallicola, E. fuscoguttatus, Epinephelus polyphekadion). For two moderately abundant species (E. faveatus and E. malabaricus), TL < Lm for all specimens. The limited data available indicate spawning ratio is lower than reported from deep-water fisheries of E. areolatus and E. coioides. The results call for targeted research to fill knowledge gaps regarding the biology and ecology of groupers exploited mainly for domestic markets; highlight the need for species-level data to inform management policies such as minimum legal size regulations; and can contribute towards species-level status assessments.

• Applied Microscopy
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• 제41권2호
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• pp.123-128
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• 2011

홍바리, Epinephelus fasciatus 난의 인공수정 전 후 난문의 미세구조적 특징을 주사형 전자현미경으로 관찰하였다. 홍바리 난문($6.6{\pm}0.41\;{\mu}m$)은 원통형의 분화구형으로 동물극에 1개가 존재하였다. 난문의 vestibular ridge는 시계방향성을 갖는 6~7개의 나선형의 내벽구조로 구성되었다. 난문의 내벽구조물인 나선형의 vestibular ridge는 인공수정 후 부풀어 올라와 돔(dome)형의 수정구로 분화 형성되었다. 홍바리 난은 부상란으로 난막표면에는 pore 가장자리에 고리형의 nodule과 pore 사이에 돌기형의 nodule이 관찰되었으나, 부착사와 유사한 보조 구조물은 관찰할 수 없었다. 난문 주변부에는 동심원상으로 크기가 다른 pore (0.15~0.55 ${\mu}m$)들이 개구된 형태로 혼재하였고, 수정 후 돔(dome)형의 수정구가 분화 형성되면서 pore들이 닫히는 현상을 보였다. 홍바리 난문의 미세구조적 특징은 바리과 어종간에 형태학적으로 상이하여, 바리과 어류의 계통분류학의 형질로 이용될 수 있다고 판단된다.

• Applied Microscopy
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• 제42권2호
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• pp.61-66
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• 2012

홍바리, Epinephelus fasciatus 정자의 미세구조적 특징을 주사형 및 투과형 전자현미경으로 관찰하였다. 홍바리 정자는 구형의 두부와 cytoplasmic sleeve와 고리형 cytoplasmic canal 입구 등으로 구성된 중편부 그리고 lateral fin을 갖는 1개의 편모로 구성된 미부로 구별된다. 정자의 핵은 구형이며, 첨체 구조물은 존재하지 않으나 이질 염색질이 과립상 덩어리 형태로 조밀하게 분포하였다. Proximal centriole과 distal centriole은 각각 수레바퀴형의 "9+0"의 축사구조를 보이며 서로 수직으로 osmophilic filaments 연결되어 있고, 핵막과도 연결되어 있었다. 중편부는 구형의 8~9개의 미토콘드리아를 포함하며, 빈공간인 cytoplasmic canal과 편모 원형질막에는 7~8개의 구형 입자를 갖는 necklace가 존재하였다. 미부는 1개의 편모를 갖으며 전형적인 "9+2"의 축사구조를 보였고, 편모에는 다양한 형태의 lateral fins을 관찰할 수 있었다. 홍바리 정자의 미세구조적 특징은 바리과 어류의 정자와 상이하여 계통분류학적 동정의 형질이 될 수 있을 뿐만아니라 정자 세포소기관의 기능적 및 생리학적 연구에 이용될 수 있다고 판단된다.

• 한국수산과학회지
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• 제37권5호
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• pp.414-422
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• 2004

To infer phylogenetic relationships among Epinephelus species inhabiting coastal regions of Korean peninsula, mitochondrial cytochrome b genes from 9 species belonging to the subfamily Epinephelinae were PCR-amplified, cloned and sequenced. Aligned cytochrome b sequences of 10 species containing one additional sequence from GenBank were 1,140 base pairs in length, including 439 variable and 330 parsimony informative sites. The cytochrome b genes of 10 species, as other vertebrates studied to date, exhibit unequal base compositions: an entirely low G content ($15.2{\pm}0.3{\%}$on average) and almost equal T, C and A contents ($29.3{\pm}0.8{\%},\;30.7{\pm}1.0{\%},\;and\;24.8{\pm}0.5{\%}$ on average, respectively).In third codon positions, transitional substitutions especially between Epinephelus species and outgroup species are almost certainly saturated or near saturation. Phylogenetic analyses were performed with sequence data from 8 Epinephelus species and 2 outgroup species (Cephalopholis urodela and Vaviola louti) by using distance-based (neighbor-joining and minimum evolution) and parsimony-based (maximum parsimony) methods. The results showed that the monophyly of the genus Epinephelus was supported by relatively high bootstrap values. However, phylogenetic relationships among E. areolatus, E. moara, E. septemfasciatus, and Epinephelus sp were poorly resolved. Within the genus Epinephelus, three resolved monophyletic groups were found: clade 1 included E. akaara and E. awoara;, clade 2 included E. fasciatus and E. merra; and clade 3 included E. akaara, E. awoara, E. fasciatus, E. merra, E. areolatus, E. moara, E. septemfasciatus and Epinephelus Sp.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 1998년도 수산관련공동학술대회발표요지집
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• pp.121.2-122
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• 1998

• 한국수산과학회지
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• 제45권1호
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• pp.17-24
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• 2012

We cloned and sequenced the cDNA encoding the $FSH{\beta}$ and $LH{\beta}$ subunits from the pituitary of the blacktip grouper Epinephelus fasciatus, which regulate vitellogenesis and maturation in vertebrates, to achieve stable and healthy gametes. The full-length cDNAs of $FSH{\beta}$ and $LH{\beta}$ were 571 bp and 617 bp, encoding 120 amino acid (aa) and 147 aa proteins, respectively. The deduced amino acid sequences of $FSH{\beta}$ and $LH{\beta}$ were highly homologous (68-97%) to those of other Perciformes; E. bruneus, Dicentrarchus labrax, Thunnus thynnus, and Pseudolabrus sieboldi. Phylogenetic analysis showed that the deduced $FSH{\beta}$ and $LH{\beta}$ amino acid sequences were categorized as a distinct subunit in the $GTH{\beta}$ family, and are closely related to the teleostei $FSH{\beta}$ and $LH{\beta}$, respectively. $FSH{\beta}$ and $LH{\beta}$ mRNA exhibited high abundance in the pituitary gland and low in other brain areas, but were not present in peripheral tissues, as determined by RT-PCR.

• 한국발생생물학회지:발생과생식
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• 제16권2호
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• pp.121-128
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• 2012

최근 여러 포유류 종에서 Kisspeptin이 그 수용체인 GPR54와 함께 GnRH 분비를 자극하여 성 성숙과 최종배란에 영향을 미친다고 보고되고 있다. 이러한 보고들은 KiSS-GPR54 system이 번식과 밀접한 연관이 있음을 제시하고 있지만, 어류에 관한 연구는 미비한 실정이다. 이 연구는 어류에서의 KiSS-GPR54 system의 생리적 기능과 번식내분비적 기능을 탐색하기 위해 홍바리 Epinephelus fasciatus 뇌에서 KiSS1, KiSS2, GPR54 mRNA의 부분 염기서열을 클로닝 하였으며, KiSS1, KiSS2, GPR54 mRNA의 각 조직별 발현을 RT-PCR을 이용하여 확인하였다. 성 성숙과 KiSS-GPR54 system과의 연관성을 확인하기 위해 생식소 발달 상태(성숙과 미성숙)에 따른 발현을 qRT-PCR을 이용하여 분석하였다. KiSS1, KiSS2, GPR54의 부분 염기서열은 각각 232 bp, 304 bp, 613 bp 였으며, 조직별 발현을 조사한 결과 공통적으로 뇌에서 발현되었다. 생식소발달에 따른 발현 양상은 KiSS1, KiSS2 mRNA의 경우 성숙 상태에서가 미성숙 상태에 비해 유의적으로 높게 발현되었다. 하지만 GPR54 mRNA의 경우 미성숙 상태에서 더 높게 발현되었다. 이러한 결과들로 미루어 보아, KiSS-GPR54 system은 홍바리에 있어 번식과 밀접한 관련이 있을 것으로 사료된다.

• 한국발생생물학회지:발생과생식
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• 제16권1호
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• pp.39-45
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• 2012

To verify the sex steroids which are involved in oocyte maturation of the blacktip grouper, $Epinephelus$ $fasciatus$, we incubated vitellogenic oocytes (0.41 and 0.50 mm in average diameter) in the presence of exogenous steroid precursor ($[^3H]17{\alpha}$-hydroxyprogesterone). Steroids were extracted, separated and identified by thin layer chromatography. The major metabolites produced were androstenedione, estradiol-$17{\beta}$, estrone and progestogens. Progestogen metabolites in the oocytes of 0.50 mm were more abundant than those of 0.41 mm. Also, we investigated the $in$ $vitro$ effects of human chorionic gonadotropin (HCG; 5, 50 and 500 $IU/m{\ell}$), $17{\alpha},20{\beta}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$) and $17{\alpha},20{\beta}$-trihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}21P$; 5, 50 and 500 $ng/m{\ell}$, respectively) on oocyte maturation. In the oocytes of 0.41 mm, treatment with 50 IU HCG stimulated GVBD ($55.30{\pm}1.20%$) compared with controls ($32.41{\pm}3.13%$, $p$<0.05). In the oocytes of 0.50 mm, treatment of $17{\alpha}20{\beta}P$ (50 and 500 $ng/m{\ell}$) stimulated GVBD ($50.13{\pm}2.52$ and $51.77{\pm}5.91%$, respectively) compared with controls ($36.81{\pm}2.89%$, $p$<0.05). Treatment with 500 IU HCG also stimulated GVBD ($49.59{\pm}5.15%$) compared with controls ($p$<0.05). Taken together, these results suggested that both HCG and $17{\alpha}20{\beta}P$ were effective on in vitro oocyte maturation and $17{\alpha}20{\beta}P$ may act as a maturation inducing hormone in blacktip grouper.